diff --git "a/S2-train.txt" "b/S2-train.txt"
new file mode 100644--- /dev/null
+++ "b/S2-train.txt"
@@ -0,0 +1,263617 @@
+Revealed O
+the O
+location-specific O
+flow B-CONPRI
+patterns E-CONPRI
+and O
+quantified O
+the O
+speeds O
+of O
+various O
+types O
+of O
+flow O
+. O
+
+
+Reconstructed O
+three-dimensional S-CONPRI
+flow B-CONPRI
+pattern E-CONPRI
+under O
+both O
+conduction-mode O
+melting S-MANP
+and O
+depression-mode O
+melting S-MANP
+. O
+
+
+Experimentally O
+analyzed O
+the O
+prevailing O
+physical B-CONPRI
+processes E-CONPRI
+at O
+different O
+locations O
+in O
+the O
+melt B-MATE
+pool E-MATE
+. O
+
+
+Melt B-CONPRI
+flow E-CONPRI
+plays O
+a O
+critical O
+role O
+in O
+laser B-MANP
+metal I-MANP
+additive I-MANP
+manufacturing E-MANP
+, O
+yet O
+the O
+melt B-CONPRI
+flow E-CONPRI
+behavior O
+within O
+the O
+melt B-MATE
+pool E-MATE
+has O
+never O
+been O
+explicitly O
+presented O
+. O
+
+
+Here O
+, O
+we O
+report O
+in-situ S-CONPRI
+characterization O
+of O
+melt-flow B-CONPRI
+dynamics E-CONPRI
+in O
+every O
+location O
+of O
+the O
+entire O
+melt B-MATE
+pool E-MATE
+in O
+laser B-MANP
+metal I-MANP
+additive I-MANP
+manufacturing E-MANP
+by O
+populous O
+and O
+uniformly O
+dispersed O
+micro-tracers O
+through O
+in-situ S-CONPRI
+high-resolution S-PARA
+synchrotron O
+x-ray B-CHAR
+imaging E-CHAR
+. O
+
+
+The O
+location-specific O
+flow B-CONPRI
+patterns E-CONPRI
+in O
+different O
+regions O
+of O
+the O
+melt B-MATE
+pool E-MATE
+are O
+revealed O
+and O
+quantified O
+under O
+both O
+conduction-mode O
+and O
+depression-mode O
+melting S-MANP
+. O
+
+
+The O
+physical B-CONPRI
+processes E-CONPRI
+at O
+different O
+locations O
+in O
+the O
+melt B-MATE
+pool E-MATE
+are O
+identified O
+. O
+
+
+The O
+full-field O
+melt-flow S-CONPRI
+mapping O
+approach O
+reported O
+here O
+opens O
+the O
+way O
+to O
+study O
+the O
+detailed O
+melt-flow B-CONPRI
+dynamics E-CONPRI
+under O
+real O
+additive B-MANP
+manufacturing E-MANP
+conditions O
+. O
+
+
+The O
+results O
+obtained O
+provide O
+crucial O
+insights O
+into O
+laser B-MANP
+additive I-MANP
+manufacturing E-MANP
+processes O
+and O
+are O
+critical O
+for O
+developing O
+reliable O
+high-fidelity S-CONPRI
+computational B-ENAT
+models E-ENAT
+. O
+
+
+High B-PARA
+resolution E-PARA
+X-ray O
+tomography O
+was O
+used O
+to O
+evaluate O
+the O
+efficiency O
+of O
+Hot B-MANP
+Isostatic I-MANP
+Pressing E-MANP
+. O
+
+
+Full O
+consolidation S-CONPRI
+of O
+large O
+internal O
+cavities O
+filled O
+with O
+unmelted O
+powder S-MATE
+was O
+demonstrated O
+. O
+
+
+Design S-FEAT
+of O
+such O
+cavities O
+with O
+unmelted O
+powder S-MATE
+could O
+improve O
+production S-MANP
+rates O
+by O
+eliminating O
+the O
+need O
+for O
+some O
+fraction S-CONPRI
+of O
+hatch O
+melting S-MANP
+in O
+the O
+interior O
+of O
+additively-manufactured O
+structures O
+. O
+
+
+HIP S-MANP
+is O
+highly O
+effective O
+at O
+closing O
+most O
+typical O
+porosity S-PRO
+distributions S-CONPRI
+. O
+
+
+Exceptions O
+are O
+highly O
+interconnected O
+pores S-PRO
+and O
+pores S-PRO
+near O
+the O
+surface S-CONPRI
+. O
+
+
+Hot B-MANP
+isostatic I-MANP
+pressing E-MANP
+( O
+HIP S-MANP
+) O
+of O
+additively B-MANP
+manufactured E-MANP
+metals O
+is O
+a O
+widely O
+adopted O
+and O
+effective O
+method O
+to O
+improve O
+the O
+density S-PRO
+and O
+microstructure S-CONPRI
+homogeneity O
+within O
+geometrically-complex S-CONPRI
+metal O
+structures O
+fabricated S-CONPRI
+with O
+laser B-MANP
+powder I-MANP
+bed I-MANP
+fusion E-MANP
+( O
+LPBF S-MANP
+) O
+. O
+
+
+The O
+role O
+of O
+pores S-PRO
+in O
+the O
+fatigue S-PRO
+performance O
+of O
+additively B-MANP
+manufactured E-MANP
+metal O
+parts O
+is O
+increasingly O
+being O
+recognized O
+as S-MATE
+a O
+critical B-PRO
+factor E-PRO
+and O
+HIP S-MANP
+post-processing O
+is O
+now O
+heralded O
+as S-MATE
+a O
+method O
+to O
+eliminate O
+pores S-PRO
+, O
+especially O
+for O
+high-criticality O
+applications O
+such O
+as S-MATE
+in O
+the O
+aerospace B-APPL
+industry E-APPL
+. O
+
+
+Despite O
+the O
+widely O
+reported O
+positive O
+influence O
+on O
+fatigue S-PRO
+performance O
+and O
+high O
+efficiency O
+of O
+pore S-PRO
+closure O
+, O
+examples O
+have O
+been O
+reported O
+in O
+which O
+pores S-PRO
+have O
+not O
+been O
+entirely O
+closed O
+or O
+have O
+subsequently O
+re-opened O
+upon O
+heat B-MANP
+treatment E-MANP
+. O
+
+
+A O
+variety O
+of O
+porosity S-PRO
+distributions S-CONPRI
+and O
+types O
+of O
+pores S-PRO
+may O
+be S-MATE
+present O
+in O
+parts O
+produced O
+by O
+LBPF O
+and O
+the O
+effectiveness S-CONPRI
+of O
+pore S-PRO
+closure O
+may O
+differ O
+depending O
+on O
+these O
+pore S-PRO
+characteristics O
+. O
+
+
+In O
+this O
+work O
+, O
+X-ray B-CHAR
+tomography E-CHAR
+was O
+employed O
+to O
+provide O
+insights O
+into O
+pore S-PRO
+closure O
+efficiency O
+by O
+HIP S-MANP
+for O
+an O
+intentional O
+and O
+artificially-induced O
+cavity O
+as S-MATE
+well O
+as S-MATE
+for O
+a O
+range S-PARA
+of O
+typical O
+process-induced O
+pores S-PRO
+( O
+lack O
+of O
+fusion S-CONPRI
+, O
+keyhole O
+, O
+contour S-FEAT
+pores O
+, O
+etc O
+. O
+
+
+) O
+in O
+coupon O
+samples S-CONPRI
+of O
+Ti6Al4V S-MATE
+. O
+
+
+The O
+same O
+samples S-CONPRI
+were O
+imaged O
+non-destructively O
+before O
+and O
+after O
+HIP S-MANP
+and O
+aligned O
+carefully O
+for O
+side-by-side O
+viewing O
+. O
+
+
+High O
+pore S-PRO
+closure O
+efficiency O
+is O
+demonstrated O
+for O
+all O
+types O
+of O
+cavities O
+and O
+pores S-PRO
+investigated O
+, O
+but O
+near-surface O
+pores S-PRO
+of O
+all O
+types O
+are O
+shown O
+to O
+be S-MATE
+problematic O
+to O
+varying O
+degrees O
+, O
+in O
+some O
+cases O
+perforating S-CONPRI
+the O
+superficial O
+surface S-CONPRI
+and O
+creating O
+new O
+external O
+notches S-FEAT
+. O
+
+
+Subsequent O
+heat B-MANP
+treatments E-MANP
+( O
+annealing S-MANP
+after O
+HIP S-MANP
+) O
+in O
+some O
+cases O
+resulted O
+in O
+internal O
+pore S-PRO
+reopening O
+for O
+previously O
+closed O
+internal O
+pores S-PRO
+as S-MATE
+well O
+as S-MATE
+a O
+new O
+“ O
+blistering O
+” O
+effect O
+observed O
+for O
+some O
+near-surface O
+pores S-PRO
+, O
+which O
+the O
+authors O
+believe O
+is O
+reported O
+for O
+the O
+first O
+time O
+. O
+
+
+Implications O
+of O
+these O
+results O
+for O
+quality B-CONPRI
+control E-CONPRI
+and O
+HIP S-MANP
+processing O
+of O
+LPBF S-MANP
+parts O
+are O
+discussed O
+. O
+
+
+Finally O
+, O
+the O
+utility O
+of O
+using O
+HIP S-MANP
+to O
+consolidate O
+intentionally-unmelted O
+powder S-MATE
+in O
+order O
+to O
+improve O
+production S-MANP
+rates O
+of O
+powder B-MANP
+bed I-MANP
+fusion E-MANP
+has O
+great O
+potential O
+and O
+is O
+preliminarily O
+demonstrated O
+. O
+
+
+Direct B-MANP
+Energy I-MANP
+Deposition E-MANP
+( O
+DED S-MANP
+) O
+systems O
+are O
+currently O
+used O
+to O
+repair O
+and O
+maintain O
+existing O
+parts O
+in O
+the O
+aerospace S-APPL
+and O
+automotive B-APPL
+industries E-APPL
+. O
+
+
+This O
+paper O
+discusses O
+an O
+effort O
+to O
+scale O
+up O
+the O
+DED S-MANP
+technique O
+in O
+order O
+to O
+Additively B-MANP
+Manufacture E-MANP
+( O
+AM S-MANP
+) O
+molds S-MACEQ
+and O
+dies S-MACEQ
+used O
+in O
+the O
+composite B-MANP
+manufacturing E-MANP
+industry O
+. O
+
+
+The O
+US O
+molds S-MACEQ
+and O
+dies S-MACEQ
+market O
+has O
+been O
+in O
+a O
+rapid O
+decline O
+over O
+the O
+last O
+decade O
+due O
+to O
+outsourcing S-CONPRI
+to O
+non-US O
+entities O
+. O
+
+
+Oak O
+Ridge O
+National O
+Laboratory S-CONPRI
+( O
+ORNL O
+) O
+, O
+Wolf O
+Robotics S-APPL
+and O
+Lincoln O
+Electric O
+have O
+developed O
+a O
+Metal B-MANP
+Big I-MANP
+Area I-MANP
+Additive I-MANP
+Manufacturing E-MANP
+( O
+MBAAM S-MANP
+) O
+system O
+that O
+uses O
+a O
+high B-PARA
+deposition I-PARA
+rate E-PARA
+and O
+a O
+low-cost O
+wire B-MATE
+feedstock I-MATE
+material E-MATE
+. O
+
+
+In O
+this O
+work O
+we O
+used O
+the O
+MBAAM S-MANP
+system O
+with O
+a O
+mild B-MATE
+steel E-MATE
+wire O
+, O
+ER70S-6 S-MATE
+, O
+to O
+fabricate S-MANP
+a O
+compression B-MANP
+molding E-MANP
+mold O
+for O
+composite B-CONPRI
+structures E-CONPRI
+used O
+in O
+automotive S-APPL
+and O
+mass-transit S-APPL
+applications O
+. O
+
+
+In O
+addition O
+, O
+the O
+mechanical B-CONPRI
+properties E-CONPRI
+of O
+the O
+AM S-MANP
+structure O
+were O
+investigated O
+, O
+and O
+it O
+was O
+found O
+that O
+the O
+MBAAM S-MANP
+process O
+delivers O
+parts O
+with O
+high O
+planar O
+isotropic S-PRO
+behavior O
+. O
+
+
+The O
+paper O
+investigates S-CONPRI
+the O
+microstructure S-CONPRI
+and O
+grain S-CONPRI
+of O
+the O
+printed O
+articles O
+to O
+confirm O
+the O
+roots O
+of O
+the O
+observed O
+planar O
+isotropic S-PRO
+properties O
+. O
+
+
+The O
+manufactured S-CONPRI
+AM B-MACEQ
+mold E-MACEQ
+was O
+used O
+to O
+fabricate S-MANP
+50 O
+composite S-MATE
+parts O
+with O
+no O
+observed O
+mold S-MACEQ
+deformations S-CONPRI
+. O
+
+
+Wire O
+feed S-PARA
+metal O
+additive B-MANP
+manufacturing E-MANP
+offers O
+advantages O
+, O
+such O
+as S-MATE
+large O
+build B-PARA
+volumes E-PARA
+and O
+high O
+build B-CHAR
+rates E-CHAR
+, O
+over O
+powder B-MACEQ
+bed E-MACEQ
+and O
+blown O
+powder S-MATE
+techniques O
+, O
+but O
+it O
+has O
+its O
+own O
+disadvantages O
+, O
+i.e. O
+, O
+lower O
+feature S-FEAT
+resolution O
+and O
+bead B-CONPRI
+morphology E-CONPRI
+control O
+issues O
+. O
+
+
+A O
+new O
+wire O
+feed S-PARA
+metal O
+additive B-MANP
+manufacturing I-MANP
+process E-MANP
+called O
+Metal B-MANP
+Big I-MANP
+Area I-MANP
+Additive I-MANP
+Manufacturing E-MANP
+( O
+mBAAM S-MANP
+) O
+uses O
+a O
+Gas B-MANP
+Metal I-MANP
+Arc I-MANP
+Weld E-MANP
+system O
+on O
+an O
+articulated O
+robot B-MACEQ
+arm E-MACEQ
+to O
+increase O
+build B-PARA
+volume E-PARA
+and O
+deposition B-PARA
+rate E-PARA
+in O
+comparison O
+to O
+powder B-MANP
+bed I-MANP
+techniques E-MANP
+. O
+
+
+The O
+high B-PARA
+deposition I-PARA
+rate E-PARA
+implies O
+a O
+low-resolution O
+process S-CONPRI
+; O
+therefore O
+, O
+parts O
+designed S-FEAT
+for O
+mBAAM S-MANP
+must O
+incorporate O
+the O
+use O
+of O
+machining S-MANP
+to O
+achieve O
+certain O
+features O
+. O
+
+
+This O
+paper O
+presents O
+an O
+introduction O
+to O
+how O
+design B-CONPRI
+rules E-CONPRI
+, O
+such O
+as S-MATE
+overhang O
+constraint O
+, O
+large O
+weld B-CONPRI
+bead E-CONPRI
+thickness O
+, O
+and O
+support B-FEAT
+structure E-FEAT
+, O
+for O
+mBAAM S-MANP
+interact O
+in O
+the O
+context O
+of O
+an O
+excavator B-MACEQ
+arm E-MACEQ
+case B-CONPRI
+study E-CONPRI
+, O
+which O
+was O
+designed S-FEAT
+using O
+topology B-FEAT
+optimization E-FEAT
+. O
+
+
+Interactive O
+database S-ENAT
+for O
+mechanical B-CONPRI
+properties E-CONPRI
+of O
+metal S-MATE
+lattice B-FEAT
+structures E-FEAT
+. O
+
+
+Lattice S-CONPRI
+Unit-cell O
+Characterization O
+Interface S-CONPRI
+for O
+Engineering S-APPL
+compiles O
+69 O
+sources O
+. O
+
+
+Lattice B-FEAT
+structure E-FEAT
+data S-CONPRI
+compiled O
+from O
+analytical O
+, O
+experimental S-CONPRI
+, O
+and O
+finite B-CONPRI
+element E-CONPRI
+. O
+
+
+Data S-CONPRI
+compilation O
+includes O
+nearly O
+1650 O
+experimental S-CONPRI
+and O
+finite B-CONPRI
+element I-CONPRI
+data I-CONPRI
+points E-CONPRI
+. O
+
+
+Lattice B-CONPRI
+data E-CONPRI
+incorporates O
+18 O
+different O
+common O
+unit B-CONPRI
+cell I-CONPRI
+topologies E-CONPRI
+. O
+
+
+With O
+the O
+ever-increasing O
+resolution S-PARA
+of O
+metal B-MANP
+additive I-MANP
+manufacturing E-MANP
+processes O
+, O
+the O
+ability O
+to O
+design S-FEAT
+and O
+fabricate S-MANP
+cellular O
+or O
+lattice B-FEAT
+structures E-FEAT
+is O
+readily O
+improving O
+. O
+
+
+While O
+there O
+are O
+few O
+limits S-CONPRI
+to O
+the O
+variety O
+of O
+unit B-CONPRI
+cell I-CONPRI
+topologies E-CONPRI
+that O
+can O
+feasibly O
+be S-MATE
+manufactured O
+, O
+there O
+is O
+little O
+known O
+about O
+the O
+effect O
+that O
+the O
+underlying O
+unit B-CONPRI
+cell I-CONPRI
+topology E-CONPRI
+has O
+on O
+lattice B-FEAT
+structure E-FEAT
+mechanical O
+performance S-CONPRI
+. O
+
+
+Increased O
+knowledge O
+of O
+lattice B-FEAT
+structure E-FEAT
+performance O
+based O
+on O
+the O
+unit B-CONPRI
+cell I-CONPRI
+topology E-CONPRI
+can O
+aid O
+in O
+appropriate O
+unit B-CONPRI
+cell E-CONPRI
+selection O
+to O
+achieve O
+desired O
+lattice B-FEAT
+structure E-FEAT
+mechanical O
+properties S-CONPRI
+. O
+
+
+The O
+objective O
+in O
+this O
+work O
+is O
+to O
+compile O
+metal S-MATE
+additively B-MANP
+manufactured E-MANP
+lattice O
+structure B-CHAR
+characterization E-CHAR
+data S-CONPRI
+found O
+in O
+the O
+literature O
+into O
+Ashby-style O
+plots O
+that O
+can O
+be S-MATE
+used O
+to O
+differentiate O
+unit B-CONPRI
+cell I-CONPRI
+topologies E-CONPRI
+and O
+guide O
+unit B-CONPRI
+cell E-CONPRI
+selection O
+. O
+
+
+Data S-CONPRI
+gathered O
+from O
+literature O
+encompasses O
+over O
+69 O
+papers O
+describing O
+18 O
+different O
+unit B-CONPRI
+cell I-CONPRI
+topologies E-CONPRI
+. O
+
+
+Data S-CONPRI
+on O
+mechanical B-CONPRI
+properties E-CONPRI
+such O
+as S-MATE
+the O
+effective O
+modulus O
+, O
+Poisson O
+’ O
+s S-MATE
+ratio O
+, O
+yield B-PRO
+strength E-PRO
+, O
+buckling B-PRO
+strength E-PRO
+, O
+and O
+plateau O
+strength S-PRO
+, O
+of O
+lattice B-FEAT
+structures E-FEAT
+from O
+analytical O
+models O
+based O
+on O
+mathematical S-CONPRI
+derivations O
+, O
+finite B-CONPRI
+element I-CONPRI
+analysis E-CONPRI
+, O
+and O
+experimental S-CONPRI
+characterization O
+was O
+gathered O
+and O
+synthesized O
+. O
+
+
+In O
+total O
+, O
+nearly O
+1,650 O
+data S-CONPRI
+points O
+for O
+experimental S-CONPRI
+and O
+finite B-CONPRI
+element I-CONPRI
+analysis E-CONPRI
+were O
+compiled O
+along O
+with O
+a O
+variety O
+of O
+analytical O
+models O
+for O
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+different O
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+
+Furthermore O
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+
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+
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+ISO S-MANS
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+standard S-CONPRI
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+
+To O
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+circular O
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+
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+
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+
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+interrupting O
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+
+Mechanical S-APPL
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+
+
+Furthermore O
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+
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+
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+
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+
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+
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+
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+
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+
+The O
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+
+This O
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+successful O
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+
+The O
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+
+Various O
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+
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+
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+part O
+geometry S-CONPRI
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+airfoil O
+geometries S-CONPRI
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+
+
+Crack O
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+
+New O
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+cracking S-CONPRI
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+utilized O
+in O
+an O
+FEM S-CONPRI
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+
+The O
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+
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+
+Because O
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+
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+
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+
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+
+The O
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+
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+
+The O
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+
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+
+It O
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+
+This O
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+
+Using O
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+NAICS O
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+
+Results O
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+
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+
+It O
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+
+Findings O
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+
+In O
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+
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+
+
+Several O
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+
+Advanced O
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+
+In O
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+
+
+It O
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+
+
+The O
+first O
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+, O
+solid B-MATE
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+, O
+and O
+cellular O
+solidification S-CONPRI
+structure O
+. O
+
+
+Finally O
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+tensile S-PRO
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+, O
+the O
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+underlying O
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+, O
+indicating O
+a O
+robust O
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+
+Thermomechanical S-CONPRI
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+FEM S-CONPRI
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+
+
+Explicit O
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+accelerated O
+( O
+30,000× O
+) O
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+time O
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+technique O
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+
+
+Real-time O
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+WAAM S-MANP
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+40 O
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+5 O
+mm3 O
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+
+Developed O
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+high O
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+predicting O
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+
+This O
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+to O
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+
+Simulation S-ENAT
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+( O
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+, O
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+( O
+DMRM O
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+, O
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+graphics O
+processing O
+unit O
+( O
+GPU O
+) O
+based O
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+analysis O
+that O
+is O
+very O
+time O
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+numerical O
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+
+
+The O
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+very O
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+experiments O
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+
+
+Compared O
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+the O
+commercial O
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+the O
+novel O
+approaches O
+reduced O
+the O
+computational O
+cost O
+substantially O
+without O
+compromising O
+accuracy S-CHAR
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+
+
+Such O
+high-fidelity S-CONPRI
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+useful O
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+building O
+up O
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+digital O
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+reduce O
+development O
+time O
+and O
+cost O
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+
+WAAM S-MANP
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+Wire-Arc-Additive-Manufacturing O
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+create O
+large O
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+high B-PARA
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+
+The O
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+wire O
+feed S-PARA
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+, O
+voltage O
+and O
+current O
+) O
+and O
+on O
+the O
+selected O
+deposition B-PARA
+path E-PARA
+. O
+
+
+Currently O
+, O
+the O
+CAM S-ENAT
+( O
+Computer-Aided-Manufacturing O
+) O
+software S-CONPRI
+dedicated O
+to O
+WAAM S-MANP
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+multi-pass O
+strategy O
+to O
+create O
+the O
+component S-MACEQ
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+
+each O
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+
+However O
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+WAAM S-MANP
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+dealing O
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+thin O
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+
+This O
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+dedicated O
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+single O
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+
+The O
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+a O
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+generate O
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+
+A O
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+
+The O
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+the O
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+
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+
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+
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+
+The O
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+
+However O
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+
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+
+Our O
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+
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+
+Our O
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+the O
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+
+The O
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+
+
+Successful O
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+the O
+same O
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+. O
+
+
+Various O
+intentional O
+and O
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+
+Porosity/defect O
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+parts O
+in O
+general O
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+
+
+Micro O
+computed B-CHAR
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+microCT S-CHAR
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+
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+) O
+liquid O
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+d O
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+microparticle O
+abrasion O
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+
+The O
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+total O
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+loss O
+were O
+established O
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+to O
+quantify O
+the O
+intensity O
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+the O
+surface B-FEAT
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+
+A O
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+quantify O
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+
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+
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+authentication O
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+
+Imaging S-APPL
+method O
+like O
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+retrieve O
+the O
+internal O
+tracking O
+code O
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+Micro-CT S-CHAR
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+code O
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+far O
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+
+Oak O
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+
+In O
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+In O
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+In O
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+Therefore O
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+A O
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+The O
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+In O
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+and O
+, O
+along O
+with O
+linear O
+crack O
+density S-PRO
+, O
+were O
+used O
+to O
+determine O
+appropriate O
+processing O
+parameters S-CONPRI
+for O
+H13 B-MATE
+tool I-MATE
+steel E-MATE
+. O
+
+
+Thermal B-CONPRI
+diffusivity E-CONPRI
+, O
+thermal B-PRO
+conductivity E-PRO
+, O
+and O
+thermal O
+capacity S-CONPRI
+were O
+measured O
+to O
+determine O
+dimensionless O
+processing O
+parameters S-CONPRI
+, O
+which O
+were O
+then O
+compared O
+to O
+others O
+reported O
+in O
+the O
+literature O
+. O
+
+
+The O
+complex O
+, O
+nonequilibrium O
+physical O
+, O
+chemical O
+, O
+and O
+metallurgical S-APPL
+nature O
+of O
+additive B-MANP
+manufacturing E-MANP
+( O
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+) O
+tends O
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+lead S-MATE
+to O
+uncontrollable O
+and O
+unpredictable O
+material S-MATE
+and O
+structural O
+properties S-CONPRI
+. O
+
+
+In O
+this O
+study O
+, O
+we O
+investigated O
+a O
+laser S-ENAT
+opto-ultrasonic O
+dual O
+( O
+LOUD O
+) O
+detection O
+approach O
+for O
+simultaneous O
+and O
+real-time O
+detection O
+of O
+elemental O
+compositions O
+, O
+structural B-CONPRI
+defects E-CONPRI
+, O
+and O
+residual B-PRO
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+in O
+aluminium S-MATE
+( O
+Al S-MATE
+) O
+alloy S-MATE
+components O
+during O
+wire B-MANP
++ I-MANP
+arc I-MANP
+additive I-MANP
+manufacturing E-MANP
+( O
+WAAM S-MANP
+) O
+processes S-CONPRI
+. O
+
+
+In O
+this O
+approach O
+, O
+a O
+pulsed-laser O
+beam S-MACEQ
+was O
+used O
+to O
+excite O
+the O
+surfaces S-CONPRI
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+Al B-MATE
+alloy E-MATE
+samples O
+to O
+generate O
+ultrasound O
+and O
+optical B-CHAR
+spectra E-CHAR
+. O
+
+
+As S-MATE
+a O
+result O
+, O
+the O
+compositional O
+information O
+can O
+be S-MATE
+obtained O
+from O
+the O
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+spectra E-CHAR
+, O
+while O
+the O
+structural B-CONPRI
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+and O
+residual B-PRO
+stress E-PRO
+distributions S-CONPRI
+can O
+be S-MATE
+extracted O
+from O
+the O
+ultrasonic O
+signals O
+. O
+
+
+The O
+silicon S-MATE
+( O
+Si S-MATE
+) O
+and O
+copper S-MATE
+( O
+Cu S-MATE
+) O
+compositions O
+obtained O
+from O
+optical S-CHAR
+spectral O
+analyses O
+are O
+consistent O
+with O
+those O
+obtained O
+from O
+the O
+electron-probe O
+microanalyses O
+( O
+EPMA S-CHAR
+) O
+. O
+
+
+The O
+1 O
+mm S-MANP
+blowhole S-CONPRI
+and O
+the O
+residual B-PRO
+stress E-PRO
+distribution S-CONPRI
+of O
+the O
+sample S-CONPRI
+were O
+detected O
+by O
+the O
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+signals O
+in O
+the O
+LOUD O
+detection O
+, O
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+shows O
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+the O
+conventional O
+ultrasonic O
+testing S-CHAR
+( O
+UT S-PRO
+) O
+. O
+
+
+Both O
+results O
+indicate O
+that O
+the O
+LOUD O
+detection O
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+the O
+promising O
+of O
+becoming O
+an O
+effective O
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+method O
+for O
+AM B-MANP
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+to O
+ensure O
+quality B-CONPRI
+control E-CONPRI
+and O
+process S-CONPRI
+feedback S-PARA
+. O
+
+
+Wire B-MANP
++ I-MANP
+Arc I-MANP
+Additive I-MANP
+Manufacturing E-MANP
+( O
+WAAM S-MANP
+) O
+has O
+already O
+proven O
+to O
+be S-MATE
+successful O
+for O
+the O
+production S-MANP
+of O
+large O
+metal S-MATE
+parts O
+. O
+
+
+However O
+, O
+there O
+are O
+still O
+no O
+specific O
+standards S-CONPRI
+available O
+to O
+label O
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+quality S-CONPRI
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+the O
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+by O
+WAAM S-MANP
+and O
+this O
+is O
+preventing O
+a O
+more O
+widespread O
+adoption O
+of O
+the O
+technique.A O
+crucial O
+step S-CONPRI
+towards O
+the O
+quality S-CONPRI
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+of O
+WAAM S-MANP
+parts O
+will O
+be S-MATE
+the O
+development O
+of O
+Non-Destructive B-CHAR
+Testing E-CHAR
+( O
+NDT S-CONPRI
+) O
+systems O
+capable O
+of O
+identifying O
+defects S-CONPRI
+while O
+parts O
+are O
+being O
+produced O
+. O
+
+
+In O
+this O
+regard O
+, O
+Eddy B-CHAR
+Current I-CHAR
+Testing E-CHAR
+( O
+ECT O
+) O
+can O
+play O
+a O
+significant O
+role O
+, O
+by O
+allowing O
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+inspection S-CHAR
+of O
+both O
+ferromagnetic O
+and O
+non-ferromagnetic O
+materials S-CONPRI
+, O
+with O
+high O
+speeds O
+and O
+without O
+contact S-APPL
+with O
+the O
+material S-MATE
+surface O
+. O
+
+
+The O
+limitation O
+here O
+is O
+that O
+commercial O
+ECT O
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+only O
+the O
+inspection S-CHAR
+of O
+surface S-CONPRI
+and O
+subsurface O
+defects.This O
+study O
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+focused O
+on O
+the O
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+customized O
+ECT O
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+for O
+the O
+inline O
+layer-by-layer S-CONPRI
+detection O
+of O
+defects S-CONPRI
+in O
+aluminium S-MATE
+WAAM O
+samples S-CONPRI
+. O
+
+
+Results O
+revealed O
+that O
+the O
+developed O
+EC O
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+were O
+able O
+to O
+locate O
+artificial O
+defects S-CONPRI
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+to O
+5 O
+mm S-MANP
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+with O
+a O
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+μm O
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+the O
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+to O
+5 O
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+ECT O
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+proved O
+to O
+surpass O
+the O
+limitation O
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+. O
+
+
+Also O
+, O
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+. O
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+
+These O
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+
+By O
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+( O
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+
+In O
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+
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+. O
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+
+Special O
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+
+Solvent O
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+. O
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+
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+the O
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+
+Sintering S-MANP
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+20 O
+% O
+. O
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+
+Using O
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+possible O
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+316 O
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+a O
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+, O
+debinding S-CONPRI
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+, O
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+achievable O
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+to O
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+, O
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+. O
+
+
+Fabricating S-MANP
+a O
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+
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+
+Microstructure S-CONPRI
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+
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+examined O
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+
+
+In O
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+
+Magnesium S-MATE
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+
+Subsequently O
+, O
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+fabrication S-MANP
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+
+Tensile B-CHAR
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+
+It O
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+bulk O
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+
+Furthermore O
+, O
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+torch O
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+, O
+the O
+finer O
+is O
+the O
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+. O
+
+
+Moreover O
+, O
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+that O
+at O
+the O
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+
+WAAM S-MANP
+( O
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+( O
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+
+Distortions O
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+manufactured S-CONPRI
+parts O
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+
+FE S-MATE
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+issues O
+, O
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+can O
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+, O
+deposition B-PARA
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+test O
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+mitigation O
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+
+
+Nevertheless O
+, O
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+to O
+reduce O
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+
+The O
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+, O
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+then O
+connected O
+by O
+means O
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+a O
+double O
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+
+This O
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+number O
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+
+The O
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+. O
+
+
+The O
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+tested O
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+means O
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+experimental S-CONPRI
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+tests O
+. O
+
+
+AlCoFeNiSmTiV O
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+new O
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+
+Elevated O
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+these O
+alloys S-MATE
+were O
+studied O
+. O
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+
+Phase S-CONPRI
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+a O
+single O
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+atmospheres O
+. O
+
+
+High O
+entropy O
+alloys S-MATE
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+attracted O
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+exceptional O
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+
+Due O
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+growing O
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+
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+
+In O
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+
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+
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+
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+deposited B-CHAR
+layers E-CHAR
+, O
+controlled O
+the O
+arc S-CONPRI
+energy O
+distribution S-CONPRI
+. O
+
+
+Hence O
+, O
+the O
+forming S-MANP
+width O
+had O
+an O
+approximately O
+linear O
+relation O
+with O
+the O
+spectral O
+intensity O
+of O
+Mg S-MATE
+( O
+a O
+constituent O
+of O
+the O
+alloy S-MATE
+used O
+for O
+the O
+wire O
+feed S-PARA
+) O
+and O
+the O
+electron O
+density S-PRO
+. O
+
+
+The O
+porosity S-PRO
+in O
+the O
+alloy S-MATE
+was O
+observed O
+to O
+be S-MATE
+caused O
+by O
+H O
+, O
+which O
+was O
+a O
+dominant O
+pollutant O
+in O
+the O
+process S-CONPRI
+. O
+
+
+Furthermore O
+, O
+the O
+correlation O
+between O
+the O
+porosity S-PRO
+and O
+H O
+spectral O
+intensity O
+was O
+observed O
+to O
+be S-MATE
+approximately O
+linear O
+. O
+
+
+However O
+, O
+no O
+significant O
+correlation O
+between O
+the O
+grain B-PRO
+size E-PRO
+and O
+the O
+spectrum O
+was O
+noticeable O
+. O
+
+
+The O
+results O
+from O
+this O
+study O
+establish O
+the O
+applicability O
+of O
+spectral O
+diagnosis O
+of O
+the O
+forming S-MANP
+size O
+and O
+the O
+porosity S-PRO
+in O
+WAAM S-MANP
+. O
+
+
+Specification S-PARA
+and O
+analysis O
+of O
+the O
+system O
+structure S-CONPRI
+and O
+components S-MACEQ
+of O
+a O
+desktop O
+additive B-MANP
+manufacturing E-MANP
+( O
+AM S-MANP
+) O
+system O
+. O
+
+
+Physical O
+modeling S-ENAT
+of O
+the O
+energy O
+consumption O
+behavior O
+of O
+the O
+desktop O
+AM S-MANP
+system O
+using O
+function-oriented O
+bond O
+graph O
+. O
+
+
+Development O
+of O
+an O
+energy O
+simulation S-ENAT
+tool O
+for O
+the O
+desktop O
+AM S-MANP
+system O
+using O
+MATLAB®/Simulink® O
+platform S-MACEQ
+. O
+
+
+Experimental S-CONPRI
+validation O
+of O
+the O
+simulation B-CHAR
+accuracy E-CHAR
+of O
+the O
+developed O
+simulation S-ENAT
+approach O
+. O
+
+
+The O
+assessment O
+and O
+minimization O
+of O
+energy O
+consumptions O
+of O
+additive B-MANP
+manufacturing E-MANP
+( O
+AM S-MANP
+) O
+processes S-CONPRI
+are O
+currently O
+emerging O
+research S-CONPRI
+tasks O
+. O
+
+
+It O
+is O
+evident O
+that O
+the O
+energy O
+consumption O
+of O
+an O
+AM B-MANP
+process E-MANP
+can O
+be S-MATE
+one O
+or O
+two O
+orders O
+of O
+magnitude S-PARA
+higher O
+than O
+conventional B-MANP
+manufacturing E-MANP
+processes O
+. O
+
+
+For O
+improving O
+the O
+sustainability B-CONPRI
+performance E-CONPRI
+of O
+AM S-MANP
+, O
+the O
+energy O
+use O
+of O
+AM S-MANP
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+evaluated O
+and O
+optimized O
+in O
+the O
+design S-FEAT
+phase O
+for O
+planning S-MANP
+products O
+and O
+AM B-MANP
+processes E-MANP
+. O
+
+
+In O
+order O
+to O
+support S-APPL
+the O
+quantification O
+and O
+evaluation O
+of O
+the O
+energy O
+consumption O
+of O
+AM S-MANP
+, O
+we O
+have O
+developed O
+an O
+energy O
+simulation S-ENAT
+of O
+a O
+desktop O
+AM S-MANP
+system O
+by O
+using O
+a O
+physical O
+modeling S-ENAT
+approach O
+. O
+
+
+Moreover O
+, O
+experiments O
+have O
+been O
+carried O
+out O
+to O
+validate O
+and O
+confirm O
+the O
+simulation B-CHAR
+accuracy E-CHAR
+and O
+reliability S-CHAR
+. O
+
+
+The O
+result O
+of O
+the O
+experimental S-CONPRI
+validation O
+has O
+shown O
+that O
+the O
+accuracy S-CHAR
+of O
+the O
+developed O
+simulation S-ENAT
+approach O
+can O
+be S-MATE
+up O
+to O
+approximately O
+98 O
+% O
+. O
+
+
+Metal B-MANP
+additive I-MANP
+manufacturing E-MANP
+is O
+moving O
+from O
+rapid B-ENAT
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+to O
+on-demand O
+manufacturing S-MANP
+and O
+even O
+to O
+serial O
+production S-MANP
+. O
+
+
+Consistent O
+part O
+quality S-CONPRI
+and O
+development O
+of O
+a O
+wider O
+range S-PARA
+of O
+available O
+materials S-CONPRI
+are O
+key O
+for O
+wider O
+adoption O
+. O
+
+
+This O
+requires O
+control O
+and O
+optimization S-CONPRI
+of O
+various O
+laser S-ENAT
+and O
+scanning B-CONPRI
+parameters E-CONPRI
+. O
+
+
+Therefore O
+, O
+process B-CONPRI
+modeling E-CONPRI
+has O
+been O
+extensively O
+pursued O
+to O
+reduce O
+experimental S-CONPRI
+runs O
+in O
+the O
+search O
+for O
+parameters S-CONPRI
+that O
+produce O
+dense O
+, O
+high-quality O
+parts O
+for O
+the O
+given O
+alloy S-MATE
+. O
+
+
+However O
+, O
+these O
+optimal O
+parameters S-CONPRI
+remain O
+machine-specific O
+if O
+conditions O
+defined O
+by O
+the O
+machine S-MACEQ
+architecture S-APPL
+are O
+not O
+considered O
+. O
+
+
+Previous O
+studies O
+have O
+shown O
+that O
+shielding O
+gas S-CONPRI
+flow O
+is O
+one O
+such O
+parameter S-CONPRI
+that O
+affects O
+porosity S-PRO
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+mechanical B-CONPRI
+properties E-CONPRI
+of O
+parts O
+produced O
+with O
+laser B-MANP
+powder I-MANP
+bed I-MANP
+fusion E-MANP
+. O
+
+
+In O
+this O
+study O
+, O
+the O
+effect O
+of O
+shielding O
+gas S-CONPRI
+flow O
+velocity O
+on O
+porosity S-PRO
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+geometry S-CONPRI
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+laser B-MANP
+powder I-MANP
+bed I-MANP
+fusion I-MANP
+additive I-MANP
+manufacturing E-MANP
+is O
+studied O
+. O
+
+
+As S-MATE
+the O
+vapor O
+plume O
+, O
+and O
+how O
+effectively O
+it O
+is O
+removed O
+by O
+the O
+shielding O
+gas S-CONPRI
+flow O
+, O
+have O
+a O
+significant O
+effect O
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+the O
+melt B-MATE
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+laser B-MANP
+powder I-MANP
+bed I-MANP
+fusion E-MANP
+, O
+models O
+aiming O
+at O
+predicting O
+the O
+melt B-MATE
+pool E-MATE
+geometry S-CONPRI
+and O
+attempts O
+to O
+transfer O
+process B-CONPRI
+parameters E-CONPRI
+from O
+one O
+machine S-MACEQ
+to O
+another O
+should O
+consider O
+the O
+effect O
+of O
+the O
+shielding O
+gas S-CONPRI
+flow O
+. O
+
+
+Nickel B-MATE
+Aluminum I-MATE
+Bronze E-MATE
+square O
+bars O
+were O
+printed O
+via O
+wire-arc B-MANP
+additive I-MANP
+manufacturing E-MANP
+. O
+
+
+Formation O
+of O
+various O
+κ-phases O
+were O
+discussed O
+and O
+compared O
+with O
+cast S-MANP
+alloy S-MATE
+. O
+
+
+Additive B-MANP
+Manufactured E-MANP
+( O
+AM S-MANP
+) O
+alloy S-MATE
+has O
+fine O
+solidification S-CONPRI
+structure O
+. O
+
+
+AM-NAB O
+exhibited O
+superior O
+tensile B-PRO
+properties E-PRO
+than O
+the O
+cast-NAB O
+. O
+
+
+As S-MATE
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+step S-CONPRI
+forward O
+toward O
+the O
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+of O
+the O
+next O
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+nickel B-MATE
+aluminum I-MATE
+bronze E-MATE
+( O
+NAB S-MATE
+) O
+components S-MACEQ
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+wire-arc B-MANP
+additive I-MANP
+manufacturing E-MANP
+( O
+WAAM S-MANP
+) O
+, O
+square O
+bars O
+were O
+printed O
+in O
+the O
+vertical S-CONPRI
+direction O
+. O
+
+
+The O
+as-built O
+microstructure S-CONPRI
+was O
+characterized O
+using O
+multi-scale O
+electron B-CHAR
+microscopy E-CHAR
+techniques O
+, O
+where O
+the O
+differences O
+in O
+phase S-CONPRI
+formation O
+were O
+compared O
+to O
+the O
+reference O
+cast-NAB O
+based O
+on O
+the O
+solidification S-CONPRI
+characteristics O
+. O
+
+
+The O
+as-cast O
+microstructure S-CONPRI
+typically O
+consists O
+of O
+Cu-rich O
+α-matrix O
+, O
+and O
+four O
+types O
+of O
+intermetallic S-MATE
+particles O
+referred O
+to O
+as S-MATE
+κ-phases O
+. O
+
+
+In O
+the O
+WAAM-NAB O
+, O
+the O
+formation O
+of O
+κI O
+was O
+suppressed O
+due O
+to O
+high O
+cooling B-PARA
+rates E-PARA
+. O
+
+
+The O
+microstructure S-CONPRI
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+finer O
+and O
+the O
+volume B-PARA
+fraction E-PARA
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+intermetallic S-MATE
+particles O
+was O
+significantly O
+lower O
+than O
+that O
+of O
+the O
+cast-NAB O
+. O
+
+
+Based O
+on O
+energy B-CHAR
+dispersive I-CHAR
+spectroscopy E-CHAR
+( O
+EDS S-CHAR
+) O
+technique O
+and O
+diffraction B-CHAR
+pattern E-CHAR
+analysis O
+using O
+transmission B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+TEM S-CHAR
+) O
+, O
+the O
+phases O
+formed O
+in O
+the O
+interdendritic O
+regions O
+were O
+identified O
+as S-MATE
+κII O
+( O
+globular O
+Fe3Al O
+) O
+and O
+κIII O
+( O
+lamellar S-CONPRI
+NiAl O
+) O
+, O
+whereas O
+numerous O
+fine O
+( O
+5–10 O
+nm O
+) O
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+κIV O
+particles S-CONPRI
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+the O
+α-matrix O
+. O
+
+
+Electron B-CHAR
+backscatter I-CHAR
+diffraction E-CHAR
+analysis O
+revealed O
+weak O
+texture S-FEAT
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+both O
+parallel O
+and O
+perpendicular O
+planes O
+to O
+the O
+building B-PARA
+direction E-PARA
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+( O
+100 O
+) O
+poles O
+rotated O
+away O
+from O
+the O
+build B-PARA
+direction E-PARA
+. O
+
+
+The O
+WAAM-NAB O
+sample S-CONPRI
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+considerably O
+higher O
+yield B-PRO
+strength E-PRO
+( O
+˜88 O
+MPa S-CONPRI
+) O
+and O
+elongation S-PRO
+( O
+˜10 O
+% O
+) O
+than O
+the O
+cast-NAB O
+, O
+but O
+the O
+gain S-PARA
+in O
+the O
+ultimate B-PRO
+tensile I-PRO
+strength E-PRO
+was O
+marginal O
+. O
+
+
+Processing O
+of O
+Inconel B-MATE
+718 E-MATE
+and O
+copper B-MATE
+alloy E-MATE
+GRCop-84 O
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+structure S-CONPRI
+using O
+laser B-MANP
+engineered I-MANP
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+shaping E-MANP
+( O
+LENS S-MANP
+) O
+. O
+
+
+A O
+compositionally O
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+layer S-PARA
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+high O
+laser B-CONPRI
+energy E-CONPRI
+input O
+helped O
+to O
+process S-CONPRI
+these O
+bimetallic O
+structures O
+. O
+
+
+The O
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+Inconel B-MATE
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+
+
+Deposition S-CONPRI
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+GRCop-84 O
+Increased O
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+of O
+Inconel B-MATE
+718 E-MATE
+by O
+∼250 O
+% O
+. O
+
+
+To O
+understand O
+processing O
+ability O
+and O
+measure O
+resultant O
+interfacial O
+and O
+thermal B-CONPRI
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+Inconel B-MATE
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+, O
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+structures O
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+fabricated S-CONPRI
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+shaping S-MANP
+( O
+LENS™ O
+) O
+, O
+a O
+commercially O
+available O
+additive B-MANP
+manufacturing E-MANP
+technique O
+. O
+
+
+It O
+was O
+hypothesized O
+that O
+additively O
+combining O
+the O
+two O
+aerospace S-APPL
+alloys O
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+form O
+a O
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+properties S-CONPRI
+compared O
+to O
+the O
+Inconel B-MATE
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+. O
+
+
+Two O
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+: O
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+GRCop-84 O
+on O
+Inconel B-MATE
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+the O
+compositional O
+gradation O
+of O
+the O
+two O
+alloys S-MATE
+. O
+
+
+Scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+SEM S-CHAR
+) O
+, O
+energy B-CHAR
+dispersive I-CHAR
+spectroscopy E-CHAR
+( O
+EDS S-CHAR
+) O
+, O
+X-ray B-CHAR
+Diffraction E-CHAR
+( O
+XRD S-CHAR
+) O
+, O
+Vickers O
+microhardness S-CONPRI
+and O
+flash S-MATE
+thermal O
+diffusivity S-CHAR
+were O
+used O
+to O
+characterize O
+these O
+bimetallic O
+structures O
+to O
+validate O
+our O
+hypothesis O
+. O
+
+
+The O
+compositional O
+gradation O
+approach O
+showed O
+a O
+gradual O
+transition S-CONPRI
+of O
+Inconel B-MATE
+718 E-MATE
+and O
+GRCop-84 O
+elements S-MATE
+at O
+the O
+interface S-CONPRI
+, O
+which O
+was O
+also O
+reflected O
+in O
+the O
+cross-sectional O
+hardness S-PRO
+profile O
+across O
+the O
+bimetallic O
+interface S-CONPRI
+. O
+
+
+SEM S-CHAR
+images S-CONPRI
+showed O
+columnar B-PRO
+grain E-PRO
+structures O
+at O
+the O
+interfaces O
+with O
+Cr2Nb O
+precipitate S-MATE
+accumulation O
+along O
+grain B-CONPRI
+boundaries E-CONPRI
+and O
+the O
+substrate-deposit O
+interface S-CONPRI
+. O
+
+
+The O
+average S-CONPRI
+thermal O
+diffusivity S-CHAR
+of O
+the O
+bimetallic O
+structure S-CONPRI
+was O
+measured O
+at O
+11.33 O
+mm2/s O
+for O
+the O
+temperature B-PARA
+range E-PARA
+of O
+50 O
+°C–300 O
+°C O
+; O
+a O
+250 O
+% O
+increase O
+in O
+diffusivity S-CHAR
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+compared O
+to O
+the O
+pure O
+Inconel B-MATE
+718 I-MATE
+alloy E-MATE
+at O
+3.20 O
+mm2/s O
+. O
+
+
+Conductivity S-PRO
+of O
+the O
+bimetallic O
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+increased O
+by O
+almost O
+300 O
+% O
+compared O
+to O
+Inconel B-MATE
+718 E-MATE
+as S-MATE
+well O
+. O
+
+
+Such O
+structures O
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+designed S-FEAT
+compositional O
+gradation O
+and O
+tailored O
+thermal B-CONPRI
+properties E-CONPRI
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+up O
+the O
+possibilities O
+of O
+multi-material S-CONPRI
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+next O
+generation O
+of O
+aerospace S-APPL
+structures O
+. O
+
+
+Depth-sensing O
+( O
+instrumented O
+) O
+indentation S-CONPRI
+testing O
+technique O
+is O
+a O
+robust O
+, O
+reliable O
+, O
+convenient O
+and O
+non-destructive O
+characterization O
+method O
+to O
+study O
+small-scale O
+mechanical B-CONPRI
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+metals S-MATE
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+alloys S-MATE
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+ambient O
+and O
+elevated O
+temperatures S-PARA
+. O
+
+
+In O
+the O
+present O
+paper O
+, O
+depth-sensing O
+indentation S-CONPRI
+creep B-PRO
+behavior E-PRO
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+an O
+additively B-MANP
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+, O
+via O
+laser B-MANP
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+fusion E-MANP
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+L-PBF S-MANP
+) O
+method O
+, O
+Ti-6Al-4V B-MATE
+alloy E-MATE
+is O
+studied O
+at O
+ambient O
+temperature S-PARA
+. O
+
+
+Indentation S-CONPRI
+creep B-CHAR
+tests E-CHAR
+were O
+performed O
+through O
+a O
+dual-stage O
+scheme O
+( O
+loading O
+followed O
+by O
+a O
+constant O
+load-holding O
+and O
+unloading O
+) O
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+different O
+peak O
+loads O
+of O
+250 O
+mN S-MATE
+, O
+350 O
+mN S-MATE
+, O
+and O
+450 O
+mN S-MATE
+with O
+holding O
+time O
+of O
+400 O
+s. O
+Creep S-PRO
+parameters O
+including O
+creep S-PRO
+rate O
+, O
+creep S-PRO
+stress O
+exponent O
+, O
+and O
+indentation S-CONPRI
+size O
+effect O
+were O
+analyzed O
+, O
+according O
+to O
+the O
+Oliver O
+and O
+Pharr O
+method O
+, O
+at O
+different O
+additive B-MANP
+manufacturing E-MANP
+scan O
+directions O
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+
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+
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+
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+
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+
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+
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+
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+
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+The O
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+suitable O
+option O
+which O
+can O
+be S-MATE
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+for O
+space O
+applications O
+. O
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+
+This O
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+( O
+AM S-MANP
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+technique O
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+
+Such O
+horns O
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+development O
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+
+In O
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+development O
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+on O
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+
+AFA O
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+functional O
+testing S-CHAR
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+space O
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+
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+processing O
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+mechanical B-CONPRI
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+characterize O
+. O
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+
+Microtensile O
+testing S-CHAR
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+providing O
+a O
+wealth O
+of O
+information O
+on O
+these O
+local O
+property B-CONPRI
+variations E-CONPRI
+. O
+
+
+Here O
+we O
+utilize O
+spatial O
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+techniques O
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+additively B-MANP
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+AlSi10Mg O
+part O
+. O
+
+
+This O
+result O
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+that O
+, O
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+least O
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+some O
+cases O
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+
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+import O
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+in O
+the O
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+mechanical B-CONPRI
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+Ti6Al4V S-MATE
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+Additive I-MANP
+Manufacturing E-MANP
+( O
+WAAM S-MANP
+) O
+technology S-CONPRI
+. O
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+
+In O
+this O
+study O
+, O
+through O
+in-situ S-CONPRI
+temperature O
+measurement S-CHAR
+, O
+the O
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+thermal O
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+the O
+gas S-CONPRI
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+additive I-MANP
+manufacturing E-MANP
+( O
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+process S-CONPRI
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+presented O
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+
+The O
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+heat B-PRO
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+microstructure S-CONPRI
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+mechanical B-CONPRI
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+Ti6Al4V O
+parts O
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+studied O
+by O
+means O
+of O
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+microscopy E-CHAR
+( O
+OM S-CHAR
+) O
+, O
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+diffraction E-CHAR
+( O
+XRD S-CHAR
+) O
+, O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+SEM S-CHAR
+) O
+, O
+energy B-CHAR
+dispersive I-CHAR
+spectrometer E-CHAR
+( O
+EDS S-CHAR
+) O
+and O
+standard S-CONPRI
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+tests O
+, O
+aiming O
+to O
+explore O
+the O
+feasibility S-CONPRI
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+fabricating S-MANP
+Ti6Al4V O
+parts O
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+using O
+localized O
+gas S-CONPRI
+shielding O
+. O
+
+
+The O
+results O
+show O
+that O
+due O
+to O
+the O
+influences O
+of O
+thermal O
+accumulation O
+, O
+the O
+layer S-PARA
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+s S-MATE
+surface O
+oxidation S-MANP
+, O
+microstructural B-CONPRI
+evolution E-CONPRI
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+grain B-PRO
+size E-PRO
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+and O
+crystalline O
+phase S-CONPRI
+vary O
+along O
+the O
+building B-PARA
+direction E-PARA
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+the O
+as-fabricated O
+wall O
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+which O
+creates O
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+mechanical B-CONPRI
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+fracture S-CONPRI
+features O
+. O
+
+
+It O
+has O
+also O
+been O
+found O
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+it O
+is O
+necessary O
+to O
+maintain O
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+process S-CONPRI
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+below O
+200 O
+°C O
+to O
+ensure O
+an O
+acceptable O
+quality S-CONPRI
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+Ti6Al4V S-MATE
+part O
+fabricated S-CONPRI
+using O
+only O
+localized O
+gas S-CONPRI
+shielding O
+in O
+an O
+otherwise O
+open O
+atmosphere O
+. O
+
+
+This O
+research S-CONPRI
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+a O
+better O
+understanding O
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+the O
+effects O
+of O
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+targeted O
+deposition S-CONPRI
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+the O
+WAAM S-MANP
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+benefit O
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+improvement O
+, O
+and O
+optimization S-CONPRI
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+
+A O
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+zero O
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+
+The O
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+ever O
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+( O
+MW S-CONPRI
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+sintering S-MANP
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+inkjet B-MANP
+3D I-MANP
+printing E-MANP
+. O
+
+
+Reduction S-CONPRI
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+sintering B-PARA
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+to O
+four O
+times O
+compared O
+to O
+conventional O
+sintering S-MANP
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+
+
+Discussion O
+on O
+thermal O
+and O
+non-thermal O
+effects O
+in O
+MW B-MANP
+sintering E-MANP
+of O
+3D B-APPL
+printed I-APPL
+parts E-APPL
+. O
+
+
+3D B-MANP
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+( O
+3DP S-MANP
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+is O
+a O
+two-step O
+additive B-MANP
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+technique O
+( O
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+which O
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+the O
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+
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+of O
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+Zr E-MATE
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+
+A O
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+, O
+vibrational B-ENAT
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+and O
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+
+For O
+the O
+first O
+time O
+, O
+microwave S-ENAT
+( O
+MW S-CONPRI
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+successfully O
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+the O
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+which O
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+primary O
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+resulting O
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+a O
+compositionally O
+zero-sum O
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+
+It O
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+found O
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+swelling S-CONPRI
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+the O
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+510 O
+°C O
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+
+As S-MATE
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+sintering S-MANP
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+a O
+conventional B-MACEQ
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+
+The O
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+
+
+Wire B-MANP
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+manufacturing E-MANP
+of O
+HSLA O
+steel S-MATE
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+
+
+Microstructure S-CONPRI
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+mechanical B-CONPRI
+properties E-CONPRI
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+related O
+to O
+the O
+thermal B-PARA
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+
+
+No O
+preferential O
+texture S-FEAT
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+, O
+leading O
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+near-isotropic O
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+
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+
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+
+High-strength O
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+( O
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+
+The O
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+the O
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+
+The O
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+
+The O
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+microstructural S-CONPRI
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+of O
+the O
+sample S-CONPRI
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+unchanged O
+. O
+
+
+i.e. O
+, O
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+same O
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+, O
+bainite S-MATE
+, O
+martensite S-MATE
+, O
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+retained B-MATE
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+present O
+for O
+all O
+heat S-CONPRI
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+
+Electron O
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+shows O
+that O
+no O
+preferential O
+texture S-FEAT
+has O
+been O
+developed O
+in O
+the O
+samples S-CONPRI
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+
+Because O
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+
+Mechanical B-CHAR
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+
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+
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+
+
+It O
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+
+Therefore O
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+
+In O
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+. O
+
+
+Utilizing O
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+the O
+as-built O
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+
+We O
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+this O
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+processing O
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+
+Our O
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+
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+has O
+the O
+potential O
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+impact S-CONPRI
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+manufacturers O
+finish O
+additively O
+built O
+parts O
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+
+
+This O
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+room O
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+texture S-FEAT
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+the O
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+diffractometer O
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+
+
+A O
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+
+Analysis O
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+body O
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+the O
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+
+It O
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+
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+. O
+
+
+A O
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+
+A O
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+setups O
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+
+The O
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+
+The O
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+
+A O
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+
+This O
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+, O
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+
+Next O
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+
+The O
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+
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+To O
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+
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+In O
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+
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+
+To O
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+compared O
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+( O
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+) O
+. O
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+
+FFF S-MANP
+allowed O
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+
+3D B-APPL
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+usefulness O
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+fully O
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+cork-based O
+filament S-MATE
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+. O
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+
+3D B-APPL
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+parts E-APPL
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+, O
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+a O
+pleasant O
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+
+
+AISI O
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+
+The O
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+
+
+The O
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+chemical B-CONPRI
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+
+The O
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+
+The O
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+higher O
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+
+This O
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+
+The O
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+that O
+was O
+classically O
+forged.A O
+preliminary O
+mechanical S-APPL
+and O
+microstructural B-CHAR
+characterization E-CHAR
+was O
+carried O
+out O
+in O
+order O
+to O
+characterize O
+the O
+material S-MATE
+and O
+compare O
+the O
+properties S-CONPRI
+of O
+3D B-MANP
+printed E-MANP
+with O
+material S-MATE
+that O
+has O
+been O
+forged O
+. O
+
+
+The O
+wear S-CONPRI
+rates O
+were O
+then O
+calculated O
+using O
+a O
+stylus B-MACEQ
+profilometer E-MACEQ
+. O
+
+
+The O
+wear S-CONPRI
+tracks O
+were O
+characterized O
+in O
+the O
+top O
+view O
+to O
+determine O
+the O
+composition S-CONPRI
+of O
+the O
+triboxide O
+layer S-PARA
+using O
+SEM-EDXS O
+and O
+Raman B-CHAR
+spectroscopy E-CHAR
+. O
+
+
+Cross B-CONPRI
+sections E-CONPRI
+of O
+the O
+samples S-CONPRI
+were O
+then O
+used O
+to O
+conduct O
+SEM S-CHAR
+analysis O
+in O
+order O
+to O
+determine O
+the O
+thickness O
+of O
+the O
+tribolayer O
+and O
+the O
+characteristics O
+of O
+the O
+strain S-PRO
+hardened S-MANP
+layer O
+. O
+
+
+EBSD S-CHAR
+mapping O
+was O
+also O
+conducted O
+on O
+the O
+same O
+samples S-CONPRI
+to O
+determine O
+the O
+regions O
+in O
+which O
+recrystallization S-CONPRI
+had O
+taken O
+place.The O
+results O
+showed O
+that O
+the O
+3D B-MANP
+printed E-MANP
+material O
+has O
+lower O
+wear S-CONPRI
+rates O
+than O
+the O
+forged O
+material S-MATE
+, O
+due O
+to O
+the O
+finer B-FEAT
+microstructure E-FEAT
+of O
+the O
+material S-MATE
+produced O
+by O
+3D S-CONPRI
+. O
+
+
+In O
+addition O
+, O
+the O
+triboxides O
+formed O
+on O
+the O
+additively B-MANP
+manufactured E-MANP
+component O
+were O
+finer O
+, O
+although O
+the O
+nature O
+of O
+the O
+oxide S-MATE
+was O
+the O
+same O
+. O
+
+
+The O
+3D B-MANP
+printed E-MANP
+material O
+showed O
+a O
+dynamic S-CONPRI
+recrystallization O
+at O
+600 O
+°C O
+, O
+while O
+the O
+forged O
+material S-MATE
+started O
+to O
+recrystallize O
+at O
+200 O
+°C O
+. O
+
+
+Medium O
+powered O
+LPBF S-MANP
+machines O
+can O
+process S-CONPRI
+pure O
+Cu S-MATE
+to O
+an O
+acceptable O
+level O
+. O
+
+
+Resistivity S-PRO
+of O
+as-built O
+Cu S-MATE
+increases O
+by O
+33 O
+% O
+depending O
+on O
+build B-PARA
+orientation E-PARA
+. O
+
+
+Resistivity S-PRO
+can O
+be S-MATE
+reduced O
+by O
+over O
+50 O
+% O
+from O
+as-built O
+conditions O
+via O
+heat B-MANP
+treatment E-MANP
+. O
+
+
+Electrical B-CHAR
+resistivity E-CHAR
+values O
+once O
+heat S-CONPRI
+treated O
+are O
+lower O
+than O
+AlSi10Mg S-MATE
+values O
+. O
+
+
+Pure O
+copper S-MATE
+is O
+an O
+excellent O
+thermal O
+and O
+electrical S-APPL
+conductor S-MATE
+, O
+however O
+, O
+attempts O
+to O
+process S-CONPRI
+it O
+with O
+additive B-MANP
+manufacturing E-MANP
+( O
+AM S-MANP
+) O
+technologies S-CONPRI
+have O
+seen O
+various O
+levels O
+of O
+success O
+. O
+
+
+While O
+electron B-MANP
+beam I-MANP
+melting E-MANP
+( O
+EBM S-MANP
+) O
+has O
+successfully O
+processed S-CONPRI
+pure O
+copper S-MATE
+to O
+high O
+densities O
+, O
+laser B-MANP
+powder I-MANP
+bed I-MANP
+fusion E-MANP
+( O
+LPBF S-MANP
+) O
+has O
+had O
+difficulties O
+achieving O
+the O
+same O
+results O
+without O
+the O
+use O
+of O
+very O
+high O
+power S-PARA
+lasers O
+. O
+
+
+This O
+requirement O
+has O
+hampered O
+the O
+exploration O
+of O
+using O
+LPBF S-MANP
+with O
+pure O
+copper S-MATE
+as S-MATE
+most O
+machines S-MACEQ
+are O
+equipped O
+with O
+lasers O
+that O
+have O
+low O
+to O
+medium O
+laser B-PARA
+power E-PARA
+densities O
+. O
+
+
+In O
+this O
+work O
+, O
+experiments O
+were O
+conducted O
+to O
+process S-CONPRI
+pure O
+copper S-MATE
+with O
+a O
+200 O
+W O
+LPBF S-MANP
+machine O
+with O
+a O
+small O
+laser S-ENAT
+spot O
+diameter S-CONPRI
+resulting O
+in O
+an O
+above O
+average S-CONPRI
+laser O
+power S-PARA
+density S-PRO
+in O
+order O
+to O
+maximise O
+density S-PRO
+and O
+achieve O
+low O
+electrical B-CHAR
+resistivity E-CHAR
+. O
+
+
+The O
+effects O
+of O
+initial O
+build B-PARA
+orientation E-PARA
+and O
+post O
+heat B-MANP
+treatment E-MANP
+were O
+also O
+investigated O
+to O
+explore O
+their O
+influence O
+on O
+electrical B-CHAR
+resistivity E-CHAR
+. O
+
+
+It O
+was O
+found O
+that O
+despite O
+issues O
+with O
+high O
+porosity S-PRO
+, O
+heat S-CONPRI
+treated O
+specimens O
+had O
+a O
+lower O
+electrical B-CHAR
+resistivity E-CHAR
+than O
+other O
+common O
+AM B-MATE
+materials E-MATE
+such O
+as S-MATE
+the O
+aluminium B-MATE
+alloy I-MATE
+AlSi10Mg E-MATE
+. O
+
+
+By O
+conducting O
+these O
+tests O
+, O
+it O
+was O
+found O
+that O
+despite O
+having O
+approximately O
+double O
+the O
+resistivity S-PRO
+of O
+commercially O
+pure O
+copper S-MATE
+, O
+the O
+resistivity S-PRO
+was O
+sufficiently O
+low O
+enough O
+to O
+demonstrate O
+the O
+potential O
+to O
+use O
+AM S-MANP
+to O
+process S-CONPRI
+copper S-MATE
+suitable O
+for O
+electrical B-APPL
+applications E-APPL
+. O
+
+
+Large O
+Area S-PARA
+Additive B-MANP
+Manufacturing E-MANP
+now O
+enables O
+the O
+fabrication S-MANP
+of O
+structures O
+that O
+are O
+dramatically O
+more O
+substantial O
+than O
+those O
+produced O
+with O
+standard S-CONPRI
+3D B-MANP
+printing E-MANP
+. O
+
+
+As S-MATE
+the O
+use O
+of O
+support B-FEAT
+structure E-FEAT
+is O
+generally O
+not O
+appropriate O
+when O
+printing O
+at O
+these O
+scales O
+, O
+understanding O
+the O
+limits S-CONPRI
+of O
+overhanging B-FEAT
+feature E-FEAT
+angles O
+is O
+necessary O
+to O
+establish O
+the O
+economic O
+case O
+for O
+using O
+large O
+3D B-MANP
+printing E-MANP
+. O
+
+
+Additionally O
+, O
+understanding O
+the O
+physics S-CONPRI
+of O
+the O
+process S-CONPRI
+is O
+paramount O
+to O
+avoiding O
+expensive O
+failed O
+prints O
+. O
+
+
+Rapid O
+sequential O
+layers O
+can O
+result O
+in O
+slumping O
+as S-MATE
+the O
+structure S-CONPRI
+retains O
+excessive O
+heat S-CONPRI
+when O
+the O
+next O
+layer S-PARA
+is O
+printed O
+. O
+
+
+The O
+model S-CONPRI
+can O
+be S-MATE
+used O
+to O
+insert S-MACEQ
+additional O
+dwell B-PARA
+times E-PARA
+after O
+each O
+layer S-PARA
+so O
+that O
+the O
+next O
+layer S-PARA
+of O
+printing O
+initiates O
+after O
+the O
+previous O
+layer S-PARA
+is O
+sufficiently O
+cool O
+such O
+that O
+the O
+existing O
+structure S-CONPRI
+is O
+appropriately O
+solidified O
+. O
+
+
+Inputs O
+to O
+the O
+model S-CONPRI
+include O
+the O
+feedstock B-MATE
+material E-MATE
+, O
+the O
+number O
+of O
+beads S-CHAR
+in O
+the O
+overhanging O
+wall O
+, O
+the O
+angle O
+of O
+overhang S-PARA
+and O
+the O
+threshold O
+of O
+failure S-CONPRI
+represented O
+as S-MATE
+out-of-plane O
+displacement O
+from O
+the O
+intended O
+geometry S-CONPRI
+. O
+
+
+The O
+proposed O
+thermal O
+model S-CONPRI
+can O
+then O
+be S-MATE
+used O
+with O
+slicing S-CONPRI
+software O
+to O
+insert S-MACEQ
+pauses O
+a O
+priori O
+, O
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+can O
+be S-MATE
+leveraged O
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+the O
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+in O
+conjunction O
+with O
+infrared S-CONPRI
+imaging S-APPL
+in O
+order O
+to O
+provide O
+in B-CONPRI
+situ E-CONPRI
+process O
+control O
+to O
+improve O
+quality S-CONPRI
+and O
+yield O
+. O
+
+
+Selective B-MANP
+Laser I-MANP
+Melting E-MANP
+( O
+SLM S-MANP
+) O
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+an O
+additive B-MANP
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+can O
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+near O
+to O
+net B-MANP
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+components S-MACEQ
+directly O
+from O
+Computer B-ENAT
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+which O
+may O
+be S-MATE
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+to O
+fabricate S-MANP
+using O
+conventional B-MANP
+manufacturing E-MANP
+methods O
+. O
+
+
+In O
+this O
+work O
+, O
+the O
+powdered B-MATE
+metals E-MATE
+used O
+as S-MATE
+the O
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+material E-MATE
+feedstock S-MATE
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+Selective B-MANP
+Laser I-MANP
+Melting E-MANP
+( O
+SLM S-MANP
+) O
+process S-CONPRI
+were O
+studied O
+. O
+
+
+SLM B-MANP
+manufacturing E-MANP
+processibility O
+of O
+nickel S-MATE
+based O
+super B-MATE
+alloy E-MATE
+, O
+powders S-MATE
+related O
+to O
+the O
+particle B-CONPRI
+Size I-CONPRI
+Distribution E-CONPRI
+( O
+PSD O
+) O
+, O
+flow O
+ability O
+, O
+mechanical B-CONPRI
+properties E-CONPRI
+and O
+microstructures S-MATE
+was O
+investigated O
+. O
+
+
+Different O
+powder S-MATE
+characterisation O
+methods O
+were O
+also O
+investigated O
+to O
+establish O
+which O
+might O
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+useful O
+for O
+SLM S-MANP
+application O
+. O
+
+
+Three O
+different O
+Inconel B-MATE
+625 E-MATE
+( O
+IN625 O
+) O
+powder B-MACEQ
+feedstock E-MACEQ
+materials S-CONPRI
+have O
+been O
+accounted O
+for O
+this O
+study O
+. O
+
+
+Firstly O
+, O
+three O
+different O
+IN625 O
+powders S-MATE
+were O
+fully O
+characterised O
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+, O
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+distribution E-CONPRI
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+flow O
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+using O
+different O
+types O
+of O
+characterisation O
+techniques O
+. O
+
+
+It O
+has O
+been O
+found O
+that O
+the O
+presence O
+of O
+any O
+significant O
+proportion O
+of O
+powder B-MATE
+particles E-MATE
+smaller O
+than O
+10-μm O
+diameter S-CONPRI
+, O
+leads O
+to O
+severe O
+agglomeration O
+and O
+make O
+SLM S-MANP
+processing O
+difficult O
+. O
+
+
+Secondly O
+, O
+coupons O
+were O
+manufactured S-CONPRI
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+SLM S-MANP
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+each O
+powder S-MATE
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+different O
+process B-CONPRI
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+, O
+which O
+were O
+analysed O
+for O
+porosity S-PRO
+and O
+mechanical B-CONPRI
+behaviour E-CONPRI
+. O
+
+
+Next O
+, O
+the O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+SEM S-CHAR
+) O
+, O
+electron O
+back O
+scattering O
+diffraction S-CHAR
+( O
+EBSD S-CHAR
+) O
+are O
+employed O
+to O
+investigate O
+the O
+microstructures S-MATE
+. O
+
+
+Finally O
+, O
+data S-CONPRI
+analysis O
+was O
+employed O
+on O
+the O
+data S-CONPRI
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+by O
+metal B-MATE
+powders E-MATE
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+, O
+SLM B-MANP
+manufacturing E-MANP
+, O
+SEM/EBSD O
+study O
+and O
+mechanical B-CONPRI
+properties E-CONPRI
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+the O
+IN625 O
+. O
+
+
+It O
+has O
+been O
+observed O
+that O
+the O
+powder S-MATE
+characteristics O
+, O
+as S-MATE
+well O
+as S-MATE
+SLM O
+process B-CONPRI
+parameters E-CONPRI
+influences O
+on O
+the O
+quality S-CONPRI
+of O
+the O
+IN625 O
+fabricated S-CONPRI
+. O
+
+
+Binder B-MANP
+jetting I-MANP
+additive I-MANP
+manufacturing E-MANP
+( O
+BJAM O
+) O
+is O
+a O
+comparatively O
+low-cost O
+process S-CONPRI
+that O
+enables O
+manufacturing S-MANP
+of O
+complex O
+and O
+customizable O
+metal S-MATE
+parts O
+. O
+
+
+This O
+process S-CONPRI
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+applied O
+to O
+low-cost O
+water-atomized O
+iron S-MATE
+powder O
+with O
+the O
+goal O
+of O
+understanding O
+the O
+effects O
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+printing O
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+maximizing O
+the O
+green O
+and O
+sintered S-MANP
+densities O
+of O
+manufactured S-CONPRI
+samples O
+, O
+respectively O
+. O
+
+
+The O
+powder S-MATE
+is O
+characterized O
+by O
+using O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+SEM S-CHAR
+) O
+and O
+particle S-CONPRI
+size O
+analysis O
+( O
+Camsizer O
+X2 O
+) O
+. O
+
+
+In O
+the O
+AM B-MANP
+process E-MANP
+, O
+the O
+effects O
+of O
+powder S-MATE
+compaction S-MANP
+, O
+layer B-PARA
+thickness E-PARA
+, O
+and O
+liquid B-MATE
+binder E-MATE
+level O
+on O
+green B-PRO
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+density S-PRO
+are O
+investigated O
+. O
+
+
+Post-process B-CONPRI
+heat E-CONPRI
+treatment O
+is O
+applied O
+to O
+selected O
+samples S-CONPRI
+, O
+and O
+suitable O
+debinding S-CONPRI
+parameters O
+are O
+studied O
+by O
+using O
+thermo-gravimetric O
+analysis O
+( O
+TGA S-CHAR
+) O
+. O
+
+
+Sintering S-MANP
+at O
+various O
+temperatures S-PARA
+and O
+durations O
+results O
+in O
+densities O
+of O
+up O
+to O
+91.3 O
+% O
+. O
+
+
+Image S-CONPRI
+processing O
+of O
+x-ray B-CHAR
+computed I-CHAR
+tomography E-CHAR
+( O
+μCT O
+) O
+scans O
+of O
+the O
+samples S-CONPRI
+reveals O
+that O
+porosity S-PRO
+distribution S-CONPRI
+is O
+affected O
+by O
+powder S-MATE
+spreading O
+, O
+and O
+gradients O
+in O
+pore S-PRO
+distribution S-CONPRI
+in O
+the O
+sample S-CONPRI
+are O
+largely O
+reduced O
+after O
+sintering S-MANP
+. O
+
+
+The O
+results O
+indicate O
+that O
+the O
+sintering S-MANP
+temperature O
+and O
+time O
+might O
+be S-MATE
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+to O
+achieve O
+target O
+densities O
+anywhere O
+in O
+the O
+range S-PARA
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+64 O
+% O
+and O
+91 O
+% O
+, O
+with O
+possibly O
+higher O
+densities O
+by O
+increasing O
+sintering B-PARA
+time E-PARA
+. O
+
+
+Binder-jetting O
+, O
+an O
+additive B-MANP
+manufacturing I-MANP
+process E-MANP
+and O
+relatively O
+low-cost B-PRO
+technology E-PRO
+is O
+utilized O
+to O
+deposit O
+complex-shaped S-CONPRI
+thin O
+ceramic B-MACEQ
+cores E-MACEQ
+. O
+
+
+In O
+this O
+study O
+, O
+for O
+enhancing O
+sintering S-MANP
+quality S-CONPRI
+, O
+a O
+decomposable O
+binder S-MATE
+was O
+prepared O
+using O
+binder-jetting O
+by O
+dispersing O
+different O
+contents O
+of O
+zirconium S-MATE
+basic O
+carbonate O
+( O
+ZBC O
+) O
+into O
+an O
+inorganic O
+colloidal B-MATE
+binder E-MATE
+. O
+
+
+The O
+effects O
+of O
+different O
+ZBC O
+contents O
+on O
+the O
+printability S-PARA
+of O
+the O
+binder S-MATE
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+the O
+performance S-CONPRI
+characteristics O
+of O
+the O
+ceramic B-MACEQ
+cores E-MACEQ
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+binder-jetting O
+were O
+investigated O
+. O
+
+
+The O
+results O
+show O
+that O
+the O
+surface B-PRO
+tension E-PRO
+of O
+the O
+binder S-MATE
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+with O
+the O
+increasing O
+of O
+ZBC O
+contents O
+, O
+indicating O
+that O
+the O
+addition O
+of O
+ZBC O
+particles S-CONPRI
+perturbs O
+the O
+interaction O
+between O
+water O
+molecules O
+. O
+
+
+The O
+presence O
+of O
+newly O
+generated O
+ZrO2 S-MATE
+particles S-CONPRI
+decomposed O
+by O
+ZBC O
+demonstrated O
+a O
+significant O
+effect O
+on O
+the O
+mechanical B-CONPRI
+properties E-CONPRI
+of O
+the O
+ceramic B-MACEQ
+cores E-MACEQ
+. O
+
+
+The O
+sintered S-MANP
+density S-PRO
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+by O
+about O
+44 O
+% O
+, O
+the O
+bending B-PRO
+strength E-PRO
+improved O
+from O
+60 O
+to O
+79 O
+MPa S-CONPRI
+, O
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+linear O
+shrinkage S-CONPRI
+decreased O
+from O
+20 O
+to O
+13 O
+% O
+after O
+sintering S-MANP
+at O
+1500 O
+°C O
+as S-MATE
+the O
+ZBC O
+content O
+was O
+increased O
+from O
+0 O
+to O
+35 O
+wt O
+% O
+. O
+
+
+Purposely O
+introduced O
+gas S-CONPRI
+pores O
+in O
+wire B-MANP
++ I-MANP
+arc I-MANP
+additive I-MANP
+manufactured E-MANP
+titanium S-MATE
+( O
+WAAM S-MANP
+Ti-6Al-4 B-MATE
+V E-MATE
+) O
+. O
+
+
+Interrupted O
+fatigue B-CHAR
+testing E-CHAR
+with O
+X-ray B-CHAR
+computed I-CHAR
+tomography E-CHAR
+scanning S-CONPRI
+at O
+intervals O
+. O
+
+
+Changes O
+in O
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+with O
+fatigue S-PRO
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+cycles O
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+
+
+Cyclic O
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+vicinity O
+of O
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+
+
+Fatigue B-PRO
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+the O
+traditional O
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+approach O
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+
+
+Porosity S-PRO
+defects S-CONPRI
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+to O
+the O
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+additive B-MANP
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+materials O
+, O
+particularly O
+for O
+parts O
+under O
+fatigue S-PRO
+loading O
+applications O
+. O
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+
+Although O
+the O
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+additive I-MANP
+manufactured E-MANP
+Ti-6Al-4 B-MATE
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+are O
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+of O
+isolated O
+pores S-PRO
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+not O
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+completely O
+avoided O
+due O
+to O
+feedstock S-MATE
+contamination O
+. O
+
+
+This O
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+contaminated O
+wires O
+to O
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+gauge B-MACEQ
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+purposely O
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+pores E-PRO
+in O
+the O
+size O
+range S-PARA
+of O
+120–250 O
+micrometres O
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+
+
+Changes O
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+periodic O
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+( O
+CT S-ENAT
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+scanning S-CONPRI
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+
+
+Prior O
+to O
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+near O
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+the O
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+
+Elastic-plastic O
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+cyclic O
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+the O
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+result O
+of O
+stress B-CHAR
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+consequently O
+for O
+an O
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+tension-tension O
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+( O
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+ratio O
+0.1 O
+) O
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+local O
+stress S-PRO
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+the O
+pore S-PRO
+root O
+became O
+a O
+tension-compression O
+nature O
+( O
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+−1.0 O
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+. O
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+
+Fatigue B-PRO
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+the O
+notch S-FEAT
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+validated O
+with O
+experimental S-CONPRI
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+
+Processing-structure-property O
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+complex O
+, O
+non-linear O
+, O
+and O
+poorly O
+understood O
+. O
+
+
+In O
+this O
+work O
+, O
+we O
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+informatics O
+workflow S-CONPRI
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+the O
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+of O
+high O
+pedigree O
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+each O
+stage O
+of O
+the O
+fused B-MANP
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+fabrication E-MANP
+( O
+FFF S-MANP
+) O
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+
+In O
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+a O
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+we O
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+the O
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+influences O
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+three O
+commercially O
+available O
+FFF S-MANP
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+. O
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+
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+that O
+relevant O
+data S-CONPRI
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+a O
+consistent O
+manner O
+. O
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+
+Acrylonitrile B-MATE
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+( O
+ABS S-MATE
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+filament S-MATE
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+to O
+print S-MANP
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+D638-14 O
+Type O
+V S-MATE
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+. O
+
+
+Data S-CONPRI
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+, O
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+principal O
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+. O
+
+
+The O
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+
+The O
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+changes O
+the O
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+
+Non-destructive O
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+
+3D S-CONPRI
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+relative O
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+printed O
+devices O
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+
+Integrated O
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+for O
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+
+Additive B-MANP
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+as S-MATE
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+
+However O
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+no O
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+
+Therefore O
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+the O
+intended O
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+
+We O
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+a O
+novel O
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+into O
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+
+We O
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+“ O
+images S-CONPRI
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+the O
+printed O
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+. O
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+
+Detailed O
+insights O
+into O
+the O
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+principle O
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+opportunities O
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+to O
+the O
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+
+The O
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+
+The O
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+
+Additionally O
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+
+Electron O
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+
+Understanding O
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+
+It O
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+
+The O
+texture S-FEAT
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+EBM S-MANP
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+same O
+order O
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+
+These O
+results O
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+well O
+with O
+previous O
+microstructural S-CONPRI
+studies O
+. O
+
+
+Additionally O
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+
+Carries O
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+
+Measures O
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+
+Develops O
+correlation O
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+
+Results O
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+Results O
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+
+Additive B-MANP
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+to O
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+
+A O
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+building O
+parts O
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+This O
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+strength S-PRO
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+
+This O
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+
+
+Measurements O
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+section O
+images S-CONPRI
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+the O
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+
+Results O
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+the O
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+different O
+values O
+of O
+these O
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+
+Key O
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+also O
+identified O
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+
+
+In O
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+Lightweight S-CONPRI
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+1 O
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+
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+. O
+
+
+Porous S-PRO
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+different O
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+
+
+In O
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+
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+
+In O
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+. O
+
+
+The O
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+histologically O
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+surface S-CONPRI
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+. O
+
+
+Field B-CHAR
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+scanning I-CHAR
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+( O
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+) O
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+assess O
+the O
+bone-implant B-FEAT
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+. O
+
+
+The O
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+( O
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+, O
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+
+Material S-MATE
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+by O
+part O
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+
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+by O
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+The O
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+metallic B-MATE
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+
+Metal S-MATE
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+scenarios O
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+( O
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+to O
+embed O
+functionality O
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+time O
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+
+Input O
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+
+Understanding O
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+In O
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+We O
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+
+Compressive O
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+An O
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+
+A O
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+
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+
+The O
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+
+The O
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+The O
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+
+All O
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+three-point B-CHAR
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+standard S-CONPRI
+specimens O
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+tray O
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+The O
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+The O
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+3D B-MANP
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+, O
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+in O
+their O
+final O
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+, O
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+their O
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+conclusion O
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+learning O
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+for O
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+
+Here O
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+a O
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+antenna O
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+on O
+the O
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+tetrahedron O
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+additive B-MANP
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+
+The O
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+
+The O
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+) O
+filament S-MATE
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+any O
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+
+These O
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+
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+
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+
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+
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+Herein O
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+
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+is O
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+out O
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+obtain O
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+geometrical O
+information O
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+
+Quasi-static S-CONPRI
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+compressive B-CHAR
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+
+The O
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+the O
+unit B-CONPRI
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+the O
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+the O
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+in O
+superior O
+compressive O
+modulus O
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+ultimate B-PRO
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+
+The O
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+
+The O
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+the O
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+
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+the O
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+with O
+the O
+increase O
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+
+In O
+the O
+case O
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+excellent O
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+
+Additive B-MANP
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+
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+
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+
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+
+We O
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+a O
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+
+We O
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+The O
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+applicable O
+Non-Destructive B-CHAR
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+techniques O
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+parts O
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+
+With O
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+view O
+of O
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+the O
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+quality S-CONPRI
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+the O
+produced O
+parts O
+needs O
+to O
+be S-MATE
+assured O
+. O
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+
+Thus O
+, O
+the O
+main O
+objective O
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+this O
+paper O
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+to O
+review O
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+
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+
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+material S-MATE
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+
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+
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+
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+, O
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+
+
+Stress S-PRO
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+in O
+the O
+175–225 O
+°C O
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+
+The O
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+
+The O
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+
+Furthermore O
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+
+This O
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+system O
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+
+
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+
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+
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+
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+
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+
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+
+We O
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+
+We O
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+
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+43 O
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+
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+
+This O
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+
+We O
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+approximation O
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+contrast O
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+
+In O
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+work O
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+
+
+Samples S-CONPRI
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+most O
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+Al-Si-10Mg O
+, O
+Inconel B-MATE
+718 E-MATE
+and O
+Ti-6Al-4V S-MATE
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+
+
+Surfaces S-CONPRI
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+orthogonal O
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+
+
+Measurement S-CHAR
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+visually O
+inspecting O
+the O
+topographic O
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+number O
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+local O
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+value O
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+the O
+areal O
+field O
+texture S-FEAT
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+
+
+Variations S-CONPRI
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+such O
+indicators O
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+measurement S-CHAR
+control O
+parameters S-CONPRI
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+varied O
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+
+
+Changes O
+in O
+magnification S-CONPRI
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+type O
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+vertical S-CONPRI
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+lateral O
+resolution S-PARA
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+investigated O
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+
+
+The O
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+created O
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+link O
+the O
+selected O
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+the O
+measured O
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+
+The O
+results O
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+the O
+measurement S-CHAR
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+parameters S-CONPRI
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+the O
+Sa O
+texture S-FEAT
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+considered O
+, O
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+variations S-CONPRI
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+to O
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+scales O
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+the O
+average S-CONPRI
+parameter O
+value O
+for O
+the O
+same O
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+objective O
+. O
+
+
+The O
+number O
+of O
+non-measured O
+points O
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+more O
+affected O
+by O
+the O
+choice O
+of O
+measurement S-CHAR
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+parameters S-CONPRI
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+
+
+However O
+, O
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+consistent O
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+the O
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+set S-APPL
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+
+
+Hot B-MANP
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+Pressing E-MANP
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+HIP S-MANP
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+is O
+a O
+technique O
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+applying O
+high O
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+a O
+fluid S-MATE
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+at O
+high O
+temperatures S-PARA
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+castings O
+and O
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+
+
+Due O
+to O
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+volumetric O
+shrinkage S-CONPRI
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+
+
+In O
+order O
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+work O
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+minimum O
+density S-PRO
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+92 O
+% O
+, O
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+
+While O
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+not O
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+the O
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+of O
+BJ S-MANP
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+fabricating S-MANP
+sufficiently O
+high-density O
+parts O
+without O
+infiltration S-CONPRI
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+
+
+In O
+this O
+work O
+, O
+detailed O
+investigations O
+on O
+the O
+effect O
+of O
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+BJ S-MANP
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+
+
+The O
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+reported O
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+
+
+A O
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+printed O
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+
+
+Both O
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+to O
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+compared O
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+
+Control O
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+AM S-MANP
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+
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+model B-CONPRI
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+electromagnetic O
+applications O
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+
+
+The O
+extent O
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+to O
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+
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+
+AM S-MANP
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+time O
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+
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+
+Implications O
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+
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+
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+refinement O
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+
+Specifically O
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+
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+
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+
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+
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+
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+In O
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+
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+
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+
+Interesting O
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+Finally O
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+geometry S-CONPRI
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+
+Processing O
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+Si S-MATE
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+wear B-PRO
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+
+
+Directed-energy O
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+matrix O
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+
+
+Specifically O
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+LENSTM O
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+– O
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+commercially O
+available O
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+used O
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+fabricate S-MANP
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+premixed-feedstock O
+powders S-MATE
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+
+
+The O
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+d O
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+to O
+not O
+only O
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+also O
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+minimized O
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+damage S-PRO
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+
+Additionally O
+, O
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+; O
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+38.1 O
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+% O
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+
+The O
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+idle O
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+
+Additionally O
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+formation O
+of O
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+tribofilm O
+on O
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+
+Such O
+composite S-MATE
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+approach O
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+multi-material S-CONPRI
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+
+We O
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+conditions O
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+
+The O
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+
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+
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+“ O
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+In O
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+
+Two O
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+The O
+first O
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+
+Surface B-FEAT
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+CT S-ENAT
+scans O
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+
+The O
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+ISO B-MANS
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+The O
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+
+Inconel B-MATE
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+
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+demonstrated O
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+
+
+Scanning B-CHAR
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+energy B-CHAR
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+to O
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+structures O
+. O
+
+
+XRD S-CHAR
+analysis O
+indicated O
+presence O
+of O
+Cr3C2 O
+phases O
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+
+
+CBL O
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+the O
+bonding B-PRO
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+formation O
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+the O
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+
+Our O
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+known O
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+running O
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+
+Hence O
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+
+Unfortunately O
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+This O
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+machine S-MACEQ
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+
+The O
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+
+The O
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+% O
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+
+The O
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+on O
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+trained O
+to O
+differentiate O
+the O
+acoustic O
+features O
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+
+In O
+view O
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+using O
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+the O
+sub-layer O
+spatial O
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+An O
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+PMMA O
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+
+Additive B-MANP
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+
+However O
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+
+Here O
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+
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+
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+
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+
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+
+On-line O
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+
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+
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+
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+
+Our O
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+
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+
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+
+Results O
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+Cs O
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+
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+, O
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+
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+
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+to O
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+
+While O
+copper S-MATE
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+a O
+potent O
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+titanium B-MATE
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+, O
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+use O
+in O
+commercial O
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+to O
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+“ O
+beta-fleck O
+” O
+problem O
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+
+This O
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+
+This O
+study O
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+on O
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+
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+
+The O
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+the O
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++ O
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+transus O
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+
+Additionally O
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+
+
+Both O
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+as S-MATE
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+∼15–18 O
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+were O
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+higher O
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+of O
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+
+
+The O
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+, O
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+by O
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+
+
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+( O
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+
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+
+However O
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+
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+
+Notably O
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+
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+
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+
+Additive B-MANP
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+
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+
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+
+The O
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+
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+
+The O
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+
+There O
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+
+For O
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+
+It O
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+loose O
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+
+This O
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+
+AR S-ENAT
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+
+Increasing O
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+
+
+Composite B-MATE
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+exploit O
+them O
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+
+
+In O
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+Ti/B4C O
++ O
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+
+
+We O
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+
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+
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+
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+
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+With O
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+
+However O
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+
+It O
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+Ti6Al4V S-MATE
+sample S-CONPRI
+is O
+characterized O
+by O
+optical B-CHAR
+microscopy E-CHAR
+and O
+X-ray B-CHAR
+computed I-CHAR
+tomography E-CHAR
+( O
+XCT O
+) O
+. O
+
+
+The O
+3D S-CONPRI
+reconstructions O
+by O
+XCT O
+show O
+that O
+the O
+fully B-PARA
+dense E-PARA
+Ti6Al4V O
+alloy S-MATE
+can O
+be S-MATE
+obtained O
+through O
+the O
+high O
+temperature S-PARA
+diffusion S-CONPRI
+and O
+high O
+pressure S-CONPRI
+compacting O
+of O
+the O
+HIP S-MANP
+sample O
+. O
+
+
+After O
+the O
+HIP S-MANP
+treatment O
+, O
+the O
+severely O
+deformed S-MANP
+grains O
+experience O
+an O
+obvious O
+growth O
+with O
+the O
+uniformly O
+distributed O
+β O
+precipitates S-MATE
+around O
+equiaxed O
+α O
+grains S-CONPRI
+. O
+
+
+The O
+tensile B-CHAR
+test E-CHAR
+shows O
+that O
+the O
+strength S-PRO
+of O
+CS O
+Ti6Al4V B-MATE
+alloys E-MATE
+can O
+be S-MATE
+largely O
+improved O
+by O
+the O
+enhanced O
+diffusion S-CONPRI
+and O
+resultant O
+metallurgical B-CONPRI
+bonding E-CONPRI
+. O
+
+
+With O
+the O
+HIP S-MANP
+treatment O
+, O
+the O
+CS O
+samples S-CONPRI
+exhibit O
+highly O
+densified S-MANP
+morphology O
+and O
+adjusted O
+microstructure S-CONPRI
+that O
+can O
+benefit O
+the O
+improvement O
+of O
+mechanical B-CONPRI
+properties E-CONPRI
+. O
+
+
+A O
+number O
+of O
+strategies O
+that O
+enable O
+lattice B-FEAT
+structures E-FEAT
+to O
+be S-MATE
+derived O
+from O
+Topology B-FEAT
+Optimisation E-FEAT
+( O
+TO O
+) O
+results O
+suitable O
+for O
+Additive B-MANP
+Manufacturing E-MANP
+( O
+AM S-MANP
+) O
+are O
+presented O
+. O
+
+
+The O
+proposed O
+strategies O
+are O
+evaluated O
+for O
+mechanical S-APPL
+performance O
+and O
+assessed O
+for O
+AM S-MANP
+specific O
+design S-FEAT
+related O
+manufacturing S-MANP
+considerations O
+. O
+
+
+Results O
+from O
+Finite B-CONPRI
+Element E-CONPRI
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+FE S-MATE
+) O
+analysis O
+for O
+the O
+two O
+loading O
+scenarios O
+considered O
+: O
+intended O
+loading O
+, O
+and O
+variability S-CONPRI
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+loading O
+, O
+provide O
+insight O
+into O
+the O
+solution S-CONPRI
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+of O
+the O
+design S-FEAT
+strategies O
+. O
+
+
+Lattice S-CONPRI
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+that O
+capitalised O
+on O
+TO O
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+found O
+to O
+be S-MATE
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+( O
+∼40–50 O
+% O
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+terms O
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+compared O
+to O
+the O
+structures O
+where O
+this O
+was O
+not O
+the O
+case O
+. O
+
+
+The O
+Graded O
+strategy O
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+to O
+be S-MATE
+the O
+most O
+desirable O
+from O
+both O
+the O
+design S-FEAT
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+manufacturing S-MANP
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+. O
+
+
+The O
+presented O
+pros-and-cons O
+for O
+the O
+various O
+proposed O
+design S-FEAT
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+provide O
+insight O
+into O
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+meeting O
+the O
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+faced S-MANP
+by O
+the O
+AM S-MANP
+design O
+community O
+. O
+
+
+Accompanying O
+the O
+increasing O
+advances O
+and O
+interest O
+in O
+Additive B-MANP
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+technologies S-CONPRI
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+increasing O
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+an O
+industrial S-APPL
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+knowledgeable O
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+technologies S-CONPRI
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+them O
+to O
+solve O
+real-world O
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+. O
+
+
+As S-MATE
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+, O
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+held O
+at O
+the O
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+Foundation O
+( O
+NSF O
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+discuss O
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+to O
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+AM S-MANP
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+its O
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+
+The O
+workshop O
+participants O
+– O
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+, O
+industry S-APPL
+, O
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+government O
+– O
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+2 O
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+( O
+3 O
+) O
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+( O
+4 O
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+( O
+5 O
+) O
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+teaming O
+and O
+ideation O
+techniques O
+to O
+nurture O
+creativity O
+. O
+
+
+First O
+, O
+ensure O
+that O
+all O
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+enable O
+them O
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+effectively O
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+realization O
+; O
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+, O
+and O
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+that O
+take O
+advantage O
+of O
+AM S-MANP
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+. O
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+
+Second O
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+a O
+national O
+network O
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+AM S-MANP
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+, O
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+NSF O
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+Technology S-CONPRI
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+activities O
+, O
+courses O
+, O
+and O
+curricula O
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+all O
+educational O
+levels O
+( O
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+) O
+. O
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+
+Fourth O
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+maker O
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+pathways O
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+
+The O
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+( O
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+
+A O
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+
+The O
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+( O
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+to O
+capture O
+the O
+dynamics O
+of O
+crack B-CONPRI
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+
+In O
+all O
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+, O
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+on O
+the O
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+each O
+specimen O
+. O
+
+
+The O
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+
+Although O
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+
+The O
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+the O
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+microcopy O
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+
+The O
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+
+Additive B-MANP
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+
+Successful O
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+the O
+bone S-BIOP
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+replace O
+the O
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+
+Bone-mimetic O
+biomaterials S-MATE
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+fixation O
+. O
+
+
+The O
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+predetermined O
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+porous S-PRO
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+for O
+tissue O
+ingrowth O
+and O
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+implant S-APPL
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+. O
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+
+The O
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+the O
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+of O
+the O
+parts O
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+healthcare O
+. O
+
+
+This O
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+novel O
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+based O
+on O
+X-ray B-CHAR
+computed I-CHAR
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+( O
+CT S-ENAT
+) O
+and O
+image S-CONPRI
+processing O
+. O
+
+
+The O
+method O
+was O
+developed O
+based O
+on O
+an O
+innovative O
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+prosthesis E-MACEQ
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+cup O
+prototype S-CONPRI
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+a O
+prescribed O
+non-uniform O
+lattice B-FEAT
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+struts O
+over O
+the O
+surface S-CONPRI
+, O
+with O
+the O
+interconnected O
+porosity S-PRO
+encouraging O
+bone S-BIOP
+adhesion S-PRO
+. O
+
+
+This O
+non-destructive O
+, O
+non-contact O
+examination O
+method O
+can O
+provide O
+information O
+of O
+the O
+interconnectivity O
+of O
+the O
+porous S-PRO
+structure O
+, O
+the O
+standard B-CHAR
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+of O
+the O
+size O
+of O
+the O
+pores S-PRO
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+local O
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+of O
+the O
+lattice B-FEAT
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+its O
+size O
+and O
+spatial B-CHAR
+distribution E-CHAR
+. O
+
+
+Fatigue S-PRO
+limit O
+of O
+L-PBF S-MANP
+maraging O
+steels S-MATE
+was O
+characterized O
+by O
+infrared S-CONPRI
+thermography O
+. O
+
+
+Different O
+manufacturing S-MANP
+strategies O
+led S-APPL
+to O
+varying O
+fatigue S-PRO
+limit O
+values O
+. O
+
+
+Printing B-MANP
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+optimization S-CONPRI
+with O
+respect O
+to O
+fatigue S-PRO
+performance O
+can O
+be S-MATE
+envisaged O
+. O
+
+
+This O
+paper O
+deals O
+with O
+the O
+fatigue S-PRO
+performance O
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+maraging B-MATE
+steels E-MATE
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+Powder B-MANP
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+using O
+a O
+laser B-CONPRI
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+L-PBF S-MANP
+) O
+. O
+
+
+The O
+objective O
+of O
+the O
+study O
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+develop O
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+method O
+for O
+the O
+rapid O
+and O
+reliable O
+characterization O
+of O
+the O
+produced O
+material S-MATE
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+s S-MATE
+fatigue S-PRO
+limit O
+using O
+infrared S-CONPRI
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+IR S-CHAR
+) O
+thermography O
+. O
+
+
+Next O
+, O
+fatigue B-CHAR
+tests E-CHAR
+instrumented O
+by O
+IR S-CHAR
+camera S-MACEQ
+were O
+processed S-CONPRI
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+heat B-CONPRI
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+reconstruction O
+to O
+measure O
+the O
+mechanical S-APPL
+dissipation O
+due O
+to O
+fatigue B-PRO
+damage E-PRO
+. O
+
+
+A O
+statistical O
+model S-CONPRI
+was O
+then O
+proposed O
+to O
+identify O
+the O
+fatigue S-PRO
+limit O
+of O
+the O
+material S-MATE
+. O
+
+
+Finally O
+, O
+a O
+practical O
+application O
+was O
+performed O
+to O
+compare O
+different O
+manufacturing S-MANP
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+using O
+the O
+same O
+powder S-MATE
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+opening O
+perspectives O
+for O
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+the O
+printing B-MANP
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+respect O
+to O
+the O
+fatigue S-PRO
+performance O
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+the O
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+
+Magnetically O
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+magnets S-APPL
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+a O
+high O
+loading O
+fraction S-CONPRI
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+70 O
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+% O
+Nd-Fe-B O
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+an O
+extrusion-based O
+additive B-MANP
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+or O
+3D B-MANP
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+system O
+that O
+enables O
+rapid O
+production S-MANP
+of O
+large O
+parts O
+. O
+
+
+The O
+density S-PRO
+of O
+the O
+printed O
+magnet S-APPL
+is O
+∼ O
+5.2 O
+g/cm3 O
+. O
+
+
+The O
+as-printed O
+magnets S-APPL
+are O
+then O
+coated S-APPL
+with O
+two O
+types O
+of O
+polymers S-MATE
+, O
+both O
+of O
+which O
+improve O
+the O
+thermal B-PRO
+stability E-PRO
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+by O
+flux S-MATE
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+loss O
+measurements O
+. O
+
+
+Tensile B-CHAR
+tests E-CHAR
+performed O
+at O
+25 O
+°C O
+and O
+100 O
+°C O
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+the O
+ultimate O
+tensile B-PRO
+stress E-PRO
+( O
+UTS S-PRO
+) O
+increases O
+with O
+increasing O
+loading O
+fraction S-CONPRI
+of O
+the O
+magnet S-APPL
+powder O
+, O
+and O
+decreases O
+with O
+increasing O
+temperature S-PARA
+. O
+
+
+AC O
+magnetic B-CHAR
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+resistivity S-PRO
+measurements O
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+that O
+the O
+3D B-MANP
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+Nd-Fe-B O
+bonded O
+magnets S-APPL
+exhibit O
+extremely O
+low O
+eddy O
+current O
+loss O
+and O
+high O
+resistivity S-PRO
+. O
+
+
+Finally O
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+during O
+the O
+powder S-MATE
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+stage O
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+the O
+process S-CONPRI
+. O
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+
+Anomaly S-CONPRI
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+and O
+classification S-CONPRI
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+implemented O
+using O
+an O
+unsupervised O
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+operating O
+on O
+a O
+moderately-sized O
+training O
+database S-ENAT
+of O
+image S-CONPRI
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+. O
+
+
+The O
+performance S-CONPRI
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+the O
+final O
+algorithm S-CONPRI
+is O
+evaluated O
+, O
+and O
+its O
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+standalone O
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+several O
+case B-CONPRI
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+
+
+The O
+mechanical S-APPL
+, O
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+
+Test O
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+examine O
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+could O
+be S-MATE
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+the O
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+
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+
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+
+The O
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+
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+, O
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+protective O
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+
+However O
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+
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+
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+
+To O
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+. O
+
+
+Laser S-ENAT
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+rough O
+, O
+fatigue-initiation O
+prone O
+, O
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+of O
+additive B-MANP
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+( O
+AM S-MANP
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+components S-MACEQ
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+
+
+LP O
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+a O
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+a O
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+
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+
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+a O
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+example O
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+
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+
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+
+In O
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+
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+
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+
+In O
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+
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+
+First O
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+
+The O
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+
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+
+The O
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+
+
+Moreover O
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+
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+
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+
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+
+In O
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+
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+
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+
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+The O
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+full O
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+
+This O
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+
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+
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+
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+
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+
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+
+
+Default O
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+67° O
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+each O
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+
+One O
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+second O
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+
+Experimental S-CONPRI
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+constant O
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+results O
+in O
+a O
+37.6 O
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+in O
+distortion S-CONPRI
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+a O
+rotated O
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+
+The O
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+
+The O
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+
+The O
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+LPBF S-MANP
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+
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+
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+
+
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+the O
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+of O
+material S-MATE
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+
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+
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+
+In O
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+% O
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+
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+
+Researchers O
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+
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+often O
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+to O
+use O
+on O
+a O
+large O
+scale O
+. O
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+
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+
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+
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+
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+
+Likewise O
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+
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+
+Increase O
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+to O
+gamma O
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+
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+
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+
+The O
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+
+In O
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+
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+
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+
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+
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+
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+
+The O
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++ O
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+, O
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+
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+
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+
+We O
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+
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+refinement E-CHAR
+, O
+and O
+the O
+precipitation S-CONPRI
+of O
+Fe3C O
+due O
+to O
+SiC S-MATE
+dissociation O
+. O
+
+
+The O
+microstructural B-CONPRI
+evolution E-CONPRI
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+studied O
+by O
+optical S-CHAR
+and O
+electron B-CHAR
+microscopy E-CHAR
+techniques O
+and O
+high O
+energy O
+synchrotron S-ENAT
+X-ray O
+diffraction S-CHAR
+. O
+
+
+Additionally O
+, O
+mechanical B-CHAR
+testing E-CHAR
+and O
+hardness S-PRO
+profiles O
+were O
+obtained O
+for O
+the O
+SiC-containing O
+and O
+SiC-free O
+parts O
+. O
+
+
+An O
+improvement O
+in O
+the O
+mechanical B-PRO
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+of O
+the O
+SiC-added O
+WAAM S-MANP
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+was O
+observed O
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+which O
+was O
+attributed O
+to O
+the O
+refined O
+grain B-CONPRI
+structure E-CONPRI
+and O
+finely O
+dispersed O
+Fe3C O
+. O
+
+
+The O
+present O
+study O
+systematically O
+investigated O
+the O
+mechanical B-CONPRI
+properties E-CONPRI
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+wire-based O
+( O
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+as S-MATE
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+steel B-MATE
+metals E-MATE
+, O
+both O
+stainless B-MATE
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+mild B-MATE
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+
+
+Graded O
+material B-CONPRI
+properties E-CONPRI
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+stainless B-MATE
+steel E-MATE
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+hardness S-PRO
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+the O
+direction O
+of O
+deposition S-CONPRI
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+in O
+Z O
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+due O
+to O
+variations S-CONPRI
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+local O
+thermal O
+histories O
+of O
+the O
+metal S-MATE
+. O
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+
+The O
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+0.55 O
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+SS304 O
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+
+During O
+wear S-CONPRI
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+beam S-MACEQ
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+observed O
+under O
+scanning B-CHAR
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+
+
+Additionally O
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+in O
+printed O
+mild B-MATE
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+( O
+ER70S O
+) O
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+vertical S-CONPRI
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+
+
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+graded O
+mechanical B-CONPRI
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+stainless B-MATE
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+the O
+processing O
+conditions O
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+with O
+locally O
+optimized O
+or O
+functionally B-CONPRI
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+mechanical O
+properties S-CONPRI
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+
+
+Lattice B-FEAT
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+are O
+frequently O
+found O
+in O
+nature O
+and O
+engineering S-APPL
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+to O
+their O
+myriad O
+attractive O
+properties S-CONPRI
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+applications O
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+molecular O
+to O
+architectural O
+scales O
+. O
+
+
+Lattices S-CONPRI
+have O
+also O
+become O
+a O
+key O
+concept O
+in O
+additive B-MANP
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+of O
+complex O
+lattices S-CONPRI
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+would O
+not O
+be S-MATE
+possible O
+otherwise O
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+
+
+While O
+design S-FEAT
+and O
+simulation S-ENAT
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+stiff O
+lattices S-CONPRI
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+common O
+, O
+here O
+we O
+present O
+a O
+digital O
+design S-FEAT
+and O
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+simulation S-ENAT
+approach O
+for O
+additive B-MANP
+manufacturing E-MANP
+of O
+soft O
+lattices S-CONPRI
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+to O
+large O
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+instabilities O
+, O
+for O
+which O
+applications O
+in O
+soft B-APPL
+robotics E-APPL
+, O
+healthcare O
+, O
+personal O
+protection O
+, O
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+design S-FEAT
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+rapidly O
+emerging O
+. O
+
+
+Our O
+framework S-CONPRI
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+design S-FEAT
+of O
+soft O
+lattices S-CONPRI
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+curved O
+members O
+conforming O
+to O
+freeform B-CONPRI
+geometries E-CONPRI
+, O
+and O
+with O
+variable O
+, O
+gradually O
+changing O
+member O
+thickness O
+and O
+material S-MATE
+, O
+allowing O
+the O
+local O
+control O
+of O
+stiffness S-PRO
+. O
+
+
+We O
+model S-CONPRI
+the O
+lattice S-CONPRI
+members O
+as S-MATE
+3D S-CONPRI
+curved O
+rods O
+and O
+using O
+a O
+spline-based O
+isogeometric O
+method O
+that O
+allows O
+the O
+efficient O
+simulation S-ENAT
+of O
+nonlinear O
+, O
+large O
+deformation S-CONPRI
+behavior O
+of O
+these O
+structures O
+directly O
+from O
+the O
+CAD S-ENAT
+geometries O
+. O
+
+
+Furthermore O
+, O
+we O
+enhance O
+the O
+formulation O
+with O
+a O
+new O
+joint S-CONPRI
+stiffening O
+approach O
+, O
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+based O
+on O
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+the O
+actual O
+node O
+geometries S-CONPRI
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+
+
+Simulation S-ENAT
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+highlighting O
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+application O
+of O
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+curved O
+soft O
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+
+
+Premelting O
+electron O
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+freeform B-MANP
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+( O
+PEBF3 O
+) O
+method O
+is O
+proposed O
+for O
+the O
+first O
+time O
+. O
+
+
+Al S-MATE
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+Ti S-MATE
+are O
+joined O
+by O
+PEBF3 O
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+no O
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+
+
+Meanwhile O
+, O
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+matrix O
+composites S-MATE
+are O
+obtained O
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+
+TiAl3 O
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+better O
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+TiAl3 O
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+
+The O
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+of O
+the O
+deposition S-CONPRI
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+TiAl3 O
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+periodically O
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+explained O
+and O
+verified O
+. O
+
+
+Premelting O
+electron O
+beam-assisted O
+freeform B-MANP
+fabrication E-MANP
+, O
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+new O
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+to O
+avoid O
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+direct O
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+pool O
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+, O
+is O
+proposed O
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+the O
+first O
+time O
+. O
+
+
+The O
+three O
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+wire O
+, O
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+into O
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+
+
+The O
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+formed O
+in O
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+it O
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+an O
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+, O
+and O
+, O
+subsequently O
+, O
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+transferred O
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+the O
+substrate S-MATE
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+solidification B-MANP
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+. O
+
+
+Finally O
+, O
+a O
+continuous O
+and O
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+process S-CONPRI
+of O
+premelting O
+electron O
+beam-assisted O
+freeform B-MANP
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+is O
+achieved O
+. O
+
+
+When O
+an O
+aluminum B-MATE
+alloy E-MATE
+was O
+deposited O
+on O
+a O
+TC4 O
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+freeform B-MANP
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+not O
+melt S-CONPRI
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+directly O
+act O
+on O
+the O
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+
+There O
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+the O
+TC4 O
+substrate S-MATE
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+
+
+Although O
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+intermetallic B-MATE
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+in O
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+and O
+the O
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+coherent O
+, O
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+( O
+101 O
+) O
+TiAl3// O
+( O
+020 O
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+Al S-MATE
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+clearly O
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+
+There O
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+no O
+cracks O
+or O
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+deposition S-CONPRI
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+
+The O
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+of O
+the O
+deposition S-CONPRI
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+
+Additive B-MANP
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+( O
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+
+
+The O
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+
+Their O
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+the O
+frequent O
+emergence O
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+often O
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+time-consuming O
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+
+
+This O
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+
+This O
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+recording O
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+from O
+finite B-CHAR
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+honeycomb B-FEAT
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+
+These O
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+
+Supported O
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+
+Additive B-MANP
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+features O
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+
+
+For O
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+specific O
+applications O
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+
+In O
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+( O
+FP-OHP O
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+design S-FEAT
+features O
+, O
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+a O
+Ti–6Al–4V O
+casing O
+and O
+a O
+closed-loop O
+, O
+circular O
+mini-channel O
+( O
+1.53 O
+mm S-MANP
+in O
+diameter S-CONPRI
+) O
+consisting O
+of O
+four O
+interconnected O
+layers O
+. O
+
+
+Venting O
+holes O
+were O
+integrated O
+to O
+intersect O
+each O
+layer S-PARA
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+allow O
+for O
+a O
+unique O
+layer-by-layer S-CONPRI
+, O
+plug-and-pressurize O
+de-powdering S-PRO
+procedure O
+. O
+
+
+The O
+device O
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+via O
+Scanning B-CHAR
+Electron I-CHAR
+Microscopy E-CHAR
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+– O
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+; O
+surface S-CONPRI
+characteristics O
+influential O
+on O
+surface/fluid O
+capillarity O
+and O
+heat B-CONPRI
+transfer E-CONPRI
+. O
+
+
+This O
+study O
+also O
+highlights O
+important O
+design S-FEAT
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+manufacturing S-MANP
+concerns O
+encountered O
+during O
+SLM S-MANP
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+channel-embedded O
+parts O
+, O
+such O
+as S-MATE
+channel O
+surface B-PARA
+quality E-PARA
+and O
+de-powdering S-PRO
+. O
+
+
+The O
+Ti–6Al–4V O
+FP-OHP O
+was O
+found O
+to O
+operate O
+successfully O
+with O
+an O
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+110 O
+W/m O
+K S-MATE
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+a O
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+50 O
+W O
+; O
+demonstrating O
+a O
+400–500 O
+% O
+increase O
+relative O
+to O
+solid O
+Ti–6Al–4V O
+. O
+
+
+This O
+paper O
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+a O
+comprehensive O
+analytical O
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+the O
+laser S-ENAT
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+LPF-AM O
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+process S-CONPRI
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+also O
+known O
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+energy O
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+
+The O
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+the O
+moving O
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+the O
+melt B-MATE
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+its O
+boundary S-FEAT
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+
+The O
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+modeled O
+with O
+Gaussian S-CONPRI
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+on O
+optical B-CHAR
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+
+
+The O
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+be S-MATE
+used O
+for O
+process S-CONPRI
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+catchment O
+efficiency O
+rapidly O
+. O
+
+
+Experimental S-CONPRI
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+Inconel B-MATE
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+6.8 O
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+catchment O
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+. O
+
+
+To O
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+functional O
+devices O
+while O
+eliminating O
+the O
+need O
+for O
+assembly S-MANP
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+a O
+multi-material B-MANP
+additive I-MANP
+manufacturing E-MANP
+technology O
+. O
+
+
+This O
+paper O
+presented O
+a O
+3D-printing S-MANP
+system O
+that O
+integrated O
+fused B-MANP
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+powder B-MANP
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+( O
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+to O
+produce O
+hybrid O
+metal S-MATE
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+
+
+PBF-printed O
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+FFF-printed O
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+, O
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+which O
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+, O
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+their O
+joining S-MANP
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+enhanced O
+by O
+laser S-ENAT
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+. O
+
+
+Tensile S-PRO
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+good O
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+strength O
+of O
+the O
+printed O
+metal/polymer O
+components S-MACEQ
+, O
+which O
+were O
+created O
+without O
+adhesives S-MATE
+. O
+
+
+In O
+addition O
+, O
+metal B-MATE
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+the O
+top O
+of O
+polymer S-MATE
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+was O
+demonstrated O
+. O
+
+
+Finally O
+, O
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+3D S-CONPRI
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+of O
+hybrid O
+stainless B-MATE
+steel E-MATE
+( O
+SS S-MATE
+316L O
+) O
+, O
+copper S-MATE
+( O
+Cu10Sn O
+) O
+and O
+polymer S-MATE
+( O
+PLA S-MATE
+, O
+PET O
+) O
+were O
+successfully O
+printed O
+and O
+their O
+potential O
+applications O
+were O
+discussed O
+. O
+
+
+Depending O
+on O
+the O
+available O
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+fusion E-MANP
+( O
+LPBF S-MANP
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+density S-PRO
+alloys S-MATE
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+not O
+be S-MATE
+feasible O
+, O
+economical O
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+required O
+. O
+
+
+Thus O
+, O
+it O
+is O
+important O
+to O
+understand O
+how O
+sub-optimal O
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+simultaneously O
+affect O
+the O
+mechanical B-CONPRI
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+alloys S-MATE
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+
+Here O
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+an O
+AlSi10Mg B-MATE
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+( O
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+and O
+T6 O
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+
+
+Defects S-CONPRI
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+characterized O
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+micro-computed B-CHAR
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+while O
+the O
+microstructure S-CONPRI
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+analysed O
+using O
+transmission S-CHAR
+and O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+. O
+
+
+The O
+as-built O
+microstructure S-CONPRI
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+dendritically-arranged O
+nano-crystalline O
+Si S-MATE
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+favourable O
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+, O
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+while O
+T6 O
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+caused O
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+properties S-CONPRI
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+
+HIP S-MANP
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+unable O
+to O
+close O
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+to O
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+, O
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+limited O
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+. O
+
+
+Defects S-CONPRI
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+) O
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+, O
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+oriented O
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+literature O
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+AlSi10Mg B-MATE
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+
+
+Interestingly O
+, O
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+Si S-MATE
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+the O
+as-built O
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+substantially O
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+toughness S-PRO
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+oriented O
+unfavourably O
+. O
+
+
+Additive B-MANP
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+in O
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+reduced O
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+
+
+Electron O
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+
+However O
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+the O
+surface B-PARA
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+accuracy S-CHAR
+of O
+the O
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+are O
+major O
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+for O
+the O
+wider O
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+this O
+technology S-CONPRI
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+enhanced O
+mechanical S-APPL
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+into O
+consideration O
+. O
+
+
+Identifying O
+the O
+origins O
+of O
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+capability O
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+
+Moreover O
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+
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+
+In O
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+
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+
+The O
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+samples B-CONPRI
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+the O
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+
+
+Given O
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+, O
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+
+To O
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+
+A O
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+for O
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+is O
+modified O
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+a O
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+
+Parts O
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+geometric O
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+the O
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+, O
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+model S-CONPRI
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+
+Implications O
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+approaches O
+are O
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+
+Rod S-MACEQ
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+AlSi10Mg S-MATE
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+those O
+of O
+cast S-MANP
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+
+
+In O
+addition O
+, O
+they O
+offered O
+mechanical B-CONPRI
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+the O
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+other O
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+
+
+TEM S-CHAR
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+that O
+the O
+microstructure S-CONPRI
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+the O
+as-built O
+samples S-CONPRI
+comprised O
+of O
+cell-like O
+structures O
+featured O
+by O
+dislocation S-CONPRI
+networks O
+and O
+Si S-MATE
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+. O
+
+
+HRTEM S-CHAR
+studies O
+revealed O
+the O
+semi-coherency O
+characteristics O
+of O
+the O
+Si S-MATE
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+
+
+After O
+deformation S-CONPRI
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+dislocation B-PRO
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+generation O
+of O
+new O
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+to O
+dislocation B-CONPRI
+motion E-CONPRI
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+
+
+The O
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+the O
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+around O
+them O
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+penetrating O
+the O
+semi-coherent O
+precipitates S-MATE
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+
+
+Strengthening S-MANP
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+recycled S-CONPRI
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+alloys S-MATE
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+in O
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+to O
+Orowan O
+mechanism S-CONPRI
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+existence O
+of O
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+( O
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+eutectic S-CONPRI
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+) O
+, O
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+( O
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+
+Due O
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+identical O
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+with O
+virgin B-MATE
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+
+
+Three O
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+AlSi10Mg_200C O
+samples S-CONPRI
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+near O
+optimum O
+process B-CONPRI
+parameters E-CONPRI
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+built O
+. O
+
+
+AlSi10Mg_200C O
+samples S-CONPRI
+with O
+very O
+low O
+surface B-PRO
+roughness E-PRO
+were O
+produced O
+. O
+
+
+AlSi10Mg_200C O
+samples S-CONPRI
+also O
+possessed O
+very O
+low O
+porosity S-PRO
+levels O
+. O
+
+
+OM S-CHAR
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+Microscopy S-CHAR
+analyses O
+were O
+performed O
+to O
+investigate O
+causality O
+. O
+
+
+Laser S-ENAT
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+aluminum B-MATE
+alloys E-MATE
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+by O
+metal S-MATE
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+cast B-MATE
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+aerospace S-APPL
+, O
+defense O
+, O
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+marine B-APPL
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+offering O
+better O
+mechanical B-CONPRI
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+less O
+porosity S-PRO
+, O
+and O
+competitive O
+fatigue S-PRO
+characteristics O
+. O
+
+
+One O
+of O
+the O
+major O
+issues O
+currently O
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+the O
+considerable O
+surface B-PRO
+roughness E-PRO
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+additively B-MANP
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+alloys S-MATE
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+such O
+as S-MATE
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+blasting O
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+machining S-MANP
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+
+
+In O
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+
+The O
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+
+In O
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+( O
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+. O
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+
+We O
+measure O
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+parts O
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+exposure S-CONPRI
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+any O
+external O
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+
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+
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+1 O
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+
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+
+The O
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+
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+
+It O
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+both O
+magnitude S-PARA
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+map O
+. O
+
+
+( O
+II O
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+
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+
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+
+The O
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+
+A O
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+
+Among O
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+
+In O
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+FFF S-MANP
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+for O
+SDS O
+, O
+powder-binder O
+mixtures O
+known O
+for O
+MIM O
+feedstocks S-MATE
+must O
+be S-MATE
+adapted O
+to O
+filament S-MATE
+requirements O
+resulting O
+in O
+adjustments O
+to O
+debinding S-CONPRI
+and O
+sintering S-MANP
+. O
+
+
+In O
+contrast O
+to O
+FFF S-MANP
+, O
+screw-based O
+material B-MANP
+extrusion E-MANP
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+capable O
+of O
+processing O
+already O
+available O
+MIM O
+feedstocks S-MATE
+, O
+but O
+machine S-MACEQ
+costs O
+are O
+high O
+due O
+to O
+complex O
+print B-MACEQ
+heads E-MACEQ
+. O
+
+
+In O
+this O
+work O
+, O
+a O
+new O
+process S-CONPRI
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+piston-based O
+feedstock S-MATE
+fabrication S-MANP
+( O
+PFF O
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+developed O
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+processing O
+already O
+available O
+MIM O
+feedstocks S-MATE
+at O
+comparable O
+costs O
+to O
+FFF S-MANP
+. O
+
+
+First O
+, O
+the O
+state O
+of O
+the O
+art S-APPL
+is O
+reviewed O
+highlighting O
+the O
+potential O
+of O
+piston-based O
+material B-MANP
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+its O
+usage O
+in O
+SDS O
+. O
+
+
+Experimental S-CONPRI
+studies O
+are O
+performed O
+to O
+validate O
+the O
+developed O
+PFF O
+printer S-MACEQ
+. O
+
+
+As S-MATE
+material O
+, O
+a O
+Ti-6Al-4V S-MATE
+MIM O
+feedstock S-MATE
+is O
+used O
+. O
+
+
+Thresholds O
+for O
+piston S-APPL
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+( O
+0.175 O
+mm/min O
+) O
+, O
+extrusion S-MANP
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+( O
+80 O
+°C O
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+, O
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+0.4 O
+mm S-MANP
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+are O
+determined O
+to O
+ensure O
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+to O
+control O
+the O
+extrusion B-MANP
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+steps O
+per O
+mm S-MANP
+. O
+
+
+With O
+these O
+thresholds O
+it O
+is O
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+that O
+a O
+constant O
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+a O
+filling O
+range S-PARA
+of O
+the O
+cylinder O
+up O
+to O
+155 O
+mm S-MANP
+. O
+
+
+Finally O
+, O
+the O
+performance S-CONPRI
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+the O
+PFF O
+system O
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+evaluated O
+in O
+terms O
+of O
+nozzle S-MACEQ
+geometry S-CONPRI
+, O
+print S-MANP
+speed O
+, O
+and O
+reproducibility S-CONPRI
+showing O
+that O
+reproducible O
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+achieved O
+at O
+a O
+maximum O
+speed O
+of O
+8.18 O
+mm/s O
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+a O
+tapered O
+FFF S-MANP
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+. O
+
+
+A O
+thermo-mechanical B-CONPRI
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+Ti–6Al–4V O
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+using O
+measurements O
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+generated O
+by O
+gasses O
+flowing O
+during O
+the O
+deposition S-CONPRI
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+
+
+In O
+directed B-MANP
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+, O
+material S-MATE
+is O
+injected O
+into O
+a O
+melt B-MATE
+pool E-MATE
+that O
+is O
+traversed O
+to O
+fill O
+in O
+a O
+cross-section O
+of O
+a O
+part O
+, O
+building O
+it O
+layer-by-layer S-CONPRI
+. O
+
+
+This O
+creates O
+large O
+thermal B-PARA
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+generate O
+plastic B-PRO
+deformation E-PRO
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+residual B-PRO
+stresses E-PRO
+. O
+
+
+Finite B-CONPRI
+element I-CONPRI
+analysis E-CONPRI
+( O
+FEA O
+) O
+is O
+often O
+used O
+to O
+study O
+these O
+phenomena O
+using O
+simple S-MANP
+assumptions O
+of O
+the O
+surface S-CONPRI
+convection O
+. O
+
+
+This O
+work O
+proposes O
+that O
+a O
+detailed O
+knowledge O
+of O
+the O
+surface S-CONPRI
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+is O
+required O
+to O
+produce O
+more O
+accurate S-CHAR
+FEA O
+results O
+. O
+
+
+The O
+surface S-CONPRI
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+generated O
+by O
+the O
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+is O
+measured O
+and O
+implemented O
+in O
+the O
+thermo-mechanical B-CONPRI
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+
+
+Three O
+depositions O
+with O
+different O
+geometries S-CONPRI
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+the O
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+of O
+the O
+residual B-PRO
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+
+
+An O
+additional O
+model S-CONPRI
+is O
+developed O
+using O
+the O
+assumption O
+of O
+free O
+convection O
+on O
+all O
+surfaces S-CONPRI
+. O
+
+
+The O
+results O
+show O
+that O
+a O
+measurement-based O
+convection O
+model S-CONPRI
+is O
+required O
+to O
+produce O
+accurate S-CHAR
+simulation O
+results O
+. O
+
+
+Easily O
+segregated O
+Cu-15Ni-8Sn O
+alloy S-MATE
+bulk O
+material S-MATE
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+fabricated S-CONPRI
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+a O
+selective B-MANP
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+( O
+SLM S-MANP
+) O
+process S-CONPRI
+. O
+
+
+The O
+microstructure S-CONPRI
+of O
+SLM-manufactured O
+Cu-15Ni-8Sn O
+alloy S-MATE
+was O
+investigated O
+using O
+optical B-CHAR
+microscopy E-CHAR
+( O
+OM S-CHAR
+) O
+, O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+SEM S-CHAR
+) O
+, O
+X-ray B-CHAR
+diffraction E-CHAR
+( O
+XRD S-CHAR
+) O
+, O
+and O
+transmission B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+TEM S-CHAR
+) O
+. O
+
+
+Differences O
+in O
+the O
+microstructures S-MATE
+and O
+elemental O
+segregation S-CONPRI
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+gas-atomized O
+alloy S-MATE
+powder O
+, O
+cast S-MANP
+ingots O
+, O
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+SLM-manufactured O
+samples S-CONPRI
+were O
+analyzed O
+. O
+
+
+The O
+statistical O
+average S-CONPRI
+grain O
+size O
+of O
+the O
+SLM-manufactured O
+Cu-15Ni-8Sn O
+alloy S-MATE
+was O
+4.03 O
+μm O
+. O
+
+
+Microstructures S-MATE
+of O
+the O
+SLM-manufactured O
+sample S-CONPRI
+were O
+mainly O
+composed O
+of O
+epitaxially O
+grown O
+slender O
+cellular B-FEAT
+structures E-FEAT
+with O
+submicron O
+widths O
+. O
+
+
+Microsegregation S-CONPRI
+was O
+detected O
+by O
+TEM S-CHAR
+, O
+and O
+80- O
+to O
+200-nm O
+Sn-enriched O
+precipitates S-MATE
+were O
+dispersed O
+between O
+cellullar O
+structures O
+. O
+
+
+Many O
+dislocations S-CONPRI
+and O
+dislocation S-CONPRI
+tangles O
+appeared O
+around O
+the O
+precipitates S-MATE
+. O
+
+
+An O
+EBSD S-CHAR
+test O
+revealed O
+that O
+most O
+local O
+misorientations O
+within O
+3 O
+degrees O
+were O
+concentrated O
+in O
+fusion S-CONPRI
+line O
+regions O
+. O
+
+
+Compared O
+with O
+cast S-MANP
+ingots O
+, O
+the O
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+strength E-PRO
+Rp0.2 O
+, O
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+strength E-PRO
+Rm O
+, O
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+A O
+, O
+and O
+elastic B-PRO
+modulus E-PRO
+E O
+of O
+the O
+SLM-manufactured O
+sample S-CONPRI
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+by O
+67 O
+% O
+, O
+24.6 O
+% O
+, O
+360 O
+% O
+, O
+and O
+7 O
+% O
+, O
+respectively O
+. O
+
+
+Moreover O
+, O
+the O
+SLM-manufactured O
+Cu-15Ni-8Sn O
+alloy S-MATE
+could O
+be S-MATE
+directly O
+aged O
+at O
+350℃ O
+for O
+12 O
+h O
+, O
+reaching O
+Rm O
+= O
+991.1 O
+MPa S-CONPRI
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+A O
+=3 O
+% O
+, O
+with O
+no O
+need O
+for O
+solid B-MATE
+solution E-MATE
+treatment O
+or O
+cold B-MANP
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+
+
+A O
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+for O
+modeling S-ENAT
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+effect O
+of O
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+experimentally B-CONPRI
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+samples S-CONPRI
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+to O
+different O
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+times E-PARA
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+
+
+The O
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+compared O
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+those O
+of O
+Inconel® O
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+no O
+allotropic O
+phase S-CONPRI
+transformation O
+, O
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+under O
+identical O
+process S-CONPRI
+conditions O
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+
+The O
+thermal O
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+workpieces O
+in O
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+known O
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+be S-MATE
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+dependent O
+on O
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+
+In O
+this O
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+dwell B-PARA
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+from O
+0 O
+to O
+40 O
+s. O
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+past O
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+690 O
+°C O
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+
+
+The O
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+
+
+These O
+predictions S-CONPRI
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+accurate S-CHAR
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+compared O
+with O
+experimental S-CONPRI
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+situ O
+and O
+post-process S-CONPRI
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+. O
+
+
+The O
+present O
+study O
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+electrically S-CONPRI
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+elements S-MATE
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+
+This O
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+a O
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+AM S-MANP
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+poor O
+robustness S-PRO
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+
+
+Specifically O
+, O
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+approach O
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+separated O
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+to O
+5 O
+axes O
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+motion O
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+traditional O
+horizontally-sliced O
+layer S-PARA
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+
+
+The O
+construction S-APPL
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+involved O
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+multiple O
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+to O
+combine O
+both O
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+digital O
+deposition S-CONPRI
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+conductive O
+material S-MATE
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+
+
+To O
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+( O
+3DP S-MANP
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+three O
+thermoplastics S-MATE
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+, O
+on O
+top O
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+printed O
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+a O
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+jetting S-MANP
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+which O
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+characteristics O
+such O
+as S-MATE
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+, O
+velocity O
+, O
+and O
+volume S-CONPRI
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+assessed O
+using O
+a O
+bespoke O
+drop O
+watching O
+system O
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+
+
+Electrical S-APPL
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+assess O
+robustness S-PRO
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+the O
+printed O
+circuits O
+. O
+
+
+Both O
+serpentine O
+and O
+straight O
+line O
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+used O
+in O
+the O
+testing S-CHAR
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+similar O
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+
+
+Monitored O
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+function O
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+hysteresis S-PRO
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+more O
+prominent O
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+and O
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+and O
+3-point O
+bending S-MANP
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+tests O
+of O
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+substrates O
+. O
+
+
+Bare O
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+encapsulated S-CONPRI
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+exhibited O
+low O
+electrical B-CHAR
+resistivity E-CHAR
+( O
+1–3*10−6 O
+Ω*m O
+) O
+, O
+and O
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+change O
+was O
+more O
+rapid O
+on O
+ABS S-MATE
+and O
+minor O
+on O
+PA S-CHAR
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+increasing O
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+flexural O
+strain S-PRO
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+to O
+1.2 O
+% O
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+
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+rapidly O
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+tracks O
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+fractured O
+during O
+repeated O
+stretching-compression O
+cycles O
+at O
+1 O
+% O
+and O
+1.2 O
+% O
+strain S-PRO
+. O
+
+
+No O
+resistance S-PRO
+changes O
+of O
+Ag O
+tracks O
+printed O
+on O
+PA S-CHAR
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+CoPA O
+were O
+observed O
+at O
+lower O
+strain S-PRO
+amplitudes O
+whereas O
+at O
+higher O
+strain S-PRO
+amplitudes O
+these O
+changes O
+were O
+the O
+lowest O
+for O
+conductive O
+tracks O
+on O
+CoPA O
+. O
+
+
+Thermal B-CHAR
+analyses E-CHAR
+were O
+conducted O
+to O
+determine O
+the O
+printed O
+material S-MATE
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+Tg S-CHAR
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+degradation S-CONPRI
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+to O
+find O
+the O
+optimum O
+annealing S-MANP
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+post O
+printing O
+. O
+
+
+The O
+novel O
+AM S-MANP
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+ability O
+to O
+fabricate S-MANP
+fully O
+functional O
+objects O
+in O
+one O
+build S-PARA
+, O
+including O
+integrated O
+printed O
+circuitry O
+and O
+embedded B-ENAT
+electronics E-ENAT
+. O
+
+
+This O
+new O
+technology S-CONPRI
+also O
+gives O
+the O
+opportunity O
+for O
+designers O
+to O
+improve O
+existing O
+products O
+, O
+as S-MATE
+well O
+as S-MATE
+create O
+new O
+products O
+with O
+the O
+added O
+advantages O
+of O
+geometrically O
+unconstrained O
+3DP S-MANP
+. O
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+
+Metal B-MATE
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+flowability O
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+
+In O
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+
+Our O
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+Electron B-MANP
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+EBM S-MANP
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+® O
+system O
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+
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+that O
+Inconel B-MATE
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+powder S-MATE
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+operations O
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+compared O
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+Ti-6Al-4V B-MATE
+powders E-MATE
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+
+
+We O
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+
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+
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+
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+
+After O
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+Predictions S-CONPRI
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+local O
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+dry O
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+
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+crack O
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+and O
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+crack O
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+interfaces O
+. O
+
+
+Regions O
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+unmelted O
+powder S-MATE
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+significant O
+stress S-PRO
+accumulations O
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+initiated O
+failure S-CONPRI
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+low O
+nominal O
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+. O
+
+
+Failure S-CONPRI
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+to O
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+unmelted O
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+
+Based O
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+defects S-CONPRI
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+preferentially O
+nucleate O
+material S-MATE
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+. O
+
+
+Furthermore O
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+defect S-CONPRI
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+
+Lattice B-FEAT
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+
+A O
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+
+However O
+, O
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+lattices S-CONPRI
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+thermal B-CONPRI
+loading E-CONPRI
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+currently O
+available O
+in O
+the O
+literature O
+. O
+
+
+In O
+this O
+study O
+, O
+a O
+custom-built O
+test O
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+used O
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+
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+
+The O
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+
+Larger O
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+
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+Here O
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+samples S-CONPRI
+sintered O
+at O
+1340 O
+°C O
+. O
+
+
+The O
+microstructures S-MATE
+of O
+additively B-MANP
+manufactured E-MANP
+( O
+AM S-MANP
+) O
+metal S-MATE
+components S-MACEQ
+have O
+been O
+shown O
+to O
+be S-MATE
+heterogeneous O
+and O
+spatially O
+variable O
+when O
+compared O
+to O
+conventionally O
+manufactured S-CONPRI
+counterparts O
+. O
+
+
+Consequently O
+, O
+the O
+mechanical B-CONPRI
+properties E-CONPRI
+of O
+AM-metal O
+parts O
+are O
+expected O
+to O
+vary O
+locally O
+within O
+their O
+volume S-CONPRI
+. O
+
+
+For O
+AM S-MANP
+structural O
+components S-MACEQ
+intended O
+to O
+operate O
+in O
+extreme O
+environments O
+, O
+including O
+high-strain-rate O
+loading O
+scenarios O
+, O
+there O
+is O
+a O
+need O
+to O
+quantify O
+variability S-CONPRI
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+mechanical S-APPL
+behavior O
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+the O
+same O
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+and O
+dynamic S-CONPRI
+strain-rates O
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+well O
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+the O
+effect O
+of O
+heat B-MANP
+treatment E-MANP
+on O
+the O
+mechanical B-CONPRI
+properties E-CONPRI
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+
+
+The O
+objective O
+of O
+this O
+study O
+is O
+to O
+investigate O
+the O
+effect O
+of O
+loading O
+direction O
+and O
+direct-age O
+hardening S-MANP
+heat O
+treatment O
+on O
+quasi-static S-CONPRI
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+mechanical O
+response O
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+an O
+Inconel B-MATE
+718 E-MATE
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+produced O
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+laser B-MANP
+powder I-MANP
+bed I-MANP
+fusion E-MANP
+using O
+manufacturer-recommended O
+processing O
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+
+
+Uniaxial O
+compression B-CHAR
+tests E-CHAR
+and O
+a O
+split-Hopkinson O
+pressure S-CONPRI
+bar O
+( O
+SHPB O
+) O
+were O
+used O
+to O
+investigate O
+the O
+quasi-static S-CONPRI
+and O
+dynamic S-CONPRI
+response O
+, O
+respectively O
+, O
+of O
+as-built O
+and O
+heat-treated S-MANP
+specimens O
+extracted S-CONPRI
+along O
+the O
+three O
+principal O
+processing O
+directions O
+. O
+
+
+Electron B-CHAR
+backscatter I-CHAR
+diffraction E-CHAR
+measurements O
+were O
+made O
+for O
+representative O
+specimens O
+within O
+the O
+build S-PARA
+domain O
+to O
+correlate O
+microstructural S-CONPRI
+features O
+to O
+observed O
+location-specific O
+mechanical S-APPL
+deformation S-CONPRI
+. O
+
+
+Results O
+from O
+both O
+quasi-static S-CONPRI
+and O
+dynamic S-CONPRI
+loading O
+show O
+that O
+the O
+recommended O
+processing O
+parameters S-CONPRI
+yield O
+a O
+homogeneous S-CONPRI
+stress-strain O
+response O
+throughout O
+the O
+material S-MATE
+volume O
+in O
+the O
+as-built O
+condition O
+. O
+
+
+Deformed S-MANP
+specimen O
+geometries S-CONPRI
+showed O
+a O
+systematic O
+and O
+repeatable O
+preferential O
+deformation S-CONPRI
+along O
+the O
+build B-PARA
+direction E-PARA
+, O
+regardless O
+of O
+condition O
+or O
+loading O
+strain B-CONPRI
+rate E-CONPRI
+when O
+loading O
+was O
+applied O
+in O
+either O
+of O
+the O
+two O
+orthogonal O
+processing O
+directions O
+. O
+
+
+The O
+deformation S-CONPRI
+dependence O
+is O
+found O
+to O
+be S-MATE
+related O
+to O
+the O
+underlying O
+, O
+process-induced O
+crystallographic O
+texture S-FEAT
+and O
+grain S-CONPRI
+morphology O
+. O
+
+
+Two O
+different O
+honeycomb B-FEAT
+structures E-FEAT
+are O
+manufactured S-CONPRI
+with O
+LENS S-MANP
+system O
+from O
+Ti-6Al-4V B-MATE
+alloy E-MATE
+. O
+
+
+Mechanical B-CONPRI
+properties E-CONPRI
+of O
+the O
+Ti-6Al-4V B-MATE
+alloy E-MATE
+are O
+determined O
+. O
+
+
+Procedure O
+for O
+acquiring O
+proper O
+data S-CONPRI
+for O
+the O
+elasto-visco-plastic O
+constitutive O
+model S-CONPRI
+is O
+presented O
+. O
+
+
+Energy-absorption O
+properties S-CONPRI
+of O
+the O
+honeycomb S-CONPRI
+cellular B-FEAT
+structures E-FEAT
+are O
+assessed O
+during O
+experimental S-CONPRI
+and O
+numerical O
+testing S-CHAR
+. O
+
+
+The O
+paper O
+presents O
+a O
+methodology S-CONPRI
+investigation O
+of O
+honeycomb S-CONPRI
+cellular B-FEAT
+structures E-FEAT
+deformation O
+process S-CONPRI
+in O
+quasi-static S-CONPRI
+compression B-CHAR
+tests E-CHAR
+. O
+
+
+Two O
+honeycomb S-CONPRI
+topologies O
+with O
+different O
+elementary O
+cells S-APPL
+were O
+designed S-FEAT
+and O
+manufactured S-CONPRI
+from O
+Ti-6Al-4 B-MATE
+V I-MATE
+alloy E-MATE
+powder S-MATE
+with O
+the O
+use O
+of O
+Laser B-MANP
+Engineered I-MANP
+Net I-MANP
+Shaping E-MANP
+( O
+LENS S-MANP
+) O
+system O
+and O
+compressed O
+using O
+a O
+universal O
+strength S-PRO
+machine S-MACEQ
+. O
+
+
+To O
+simulate O
+the O
+deformation S-CONPRI
+process O
+with O
+LS-Dyna O
+software S-CONPRI
+, O
+the O
+mechanical B-CONPRI
+properties E-CONPRI
+of O
+the O
+material S-MATE
+were O
+assessed O
+and O
+correlated S-CONPRI
+. O
+
+
+An O
+elasto-visco-plastic O
+material S-MATE
+model O
+( O
+Mat_Plasticity_With_Damage O
+) O
+was O
+used O
+for O
+predicting O
+the O
+material S-MATE
+behavior O
+. O
+
+
+The O
+results O
+of O
+experimental S-CONPRI
+tests O
+and O
+numerical B-ENAT
+simulations E-ENAT
+were O
+compared O
+. O
+
+
+A O
+reasonable O
+agreement O
+between O
+deformation S-CONPRI
+, O
+failure S-CONPRI
+and O
+force S-CONPRI
+histories O
+was O
+obtained O
+. O
+
+
+Additionally O
+, O
+both O
+the O
+topologies S-CONPRI
+were O
+compared O
+for O
+their O
+energy B-CHAR
+absorption E-CHAR
+capabilities O
+. O
+
+
+The O
+validated O
+numerical O
+modelling S-ENAT
+with O
+the O
+adopted O
+constitutive O
+model S-CONPRI
+will O
+be S-MATE
+used O
+in O
+the O
+further O
+studies O
+to O
+analyze O
+different O
+cellular B-FEAT
+structures E-FEAT
+topologies O
+subjected O
+to O
+dynamic S-CONPRI
+loading O
+. O
+
+
+A O
+novel O
+technique O
+was O
+developed O
+to O
+control O
+the O
+microstructure B-CONPRI
+evolution E-CONPRI
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+Alloy S-MATE
+718 O
+processed S-CONPRI
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+Electron B-MANP
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+( O
+EBM S-MANP
+) O
+. O
+
+
+In B-CONPRI
+situ E-CONPRI
+solution O
+treatment O
+and O
+aging O
+of O
+Alloy S-MATE
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+by O
+heating S-MANP
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+top O
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+the O
+build S-PARA
+after O
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+completion O
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+an O
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+beam E-CONPRI
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+a O
+planar O
+heat B-CONPRI
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+the O
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+down E-PARA
+process O
+. O
+
+
+Results O
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+that O
+the O
+measured O
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+( O
+478 O
+± O
+7 O
+HV O
+) O
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+the O
+material S-MATE
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+in B-CONPRI
+situ E-CONPRI
+heat B-MANP
+treatment E-MANP
+similar O
+to O
+that O
+of O
+peak-aged O
+Inconel B-MATE
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+. O
+
+
+Large O
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+, O
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+are O
+identified O
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+the O
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+under O
+loading O
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+
+
+Despite O
+poor O
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+( O
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+removing O
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+the O
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+chamber O
+, O
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+can O
+reduce O
+the O
+number O
+of O
+process S-CONPRI
+steps O
+in O
+producing O
+a O
+part O
+. O
+
+
+Tighter O
+controls O
+on O
+processing O
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+layer S-PARA
+melting O
+to O
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+for O
+improving O
+the O
+process S-CONPRI
+. O
+
+
+Lattice B-FEAT
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+isotropic S-PRO
+stiffness O
+fabricated S-CONPRI
+via O
+electron B-MANP
+beam I-MANP
+melting E-MANP
+. O
+
+
+The O
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+were O
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+on O
+topology B-FEAT
+optimization E-FEAT
+and O
+additive B-MANP
+manufacturing E-MANP
+. O
+
+
+The O
+designed S-FEAT
+isotropic O
+stiffness S-PRO
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+experimentally O
+verified O
+. O
+
+
+The O
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+also O
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+the O
+same O
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+stiffness S-PRO
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+
+
+Electron-beam O
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+( O
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+advantages O
+over O
+other O
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+its O
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+, O
+rapid B-MANP
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+speed O
+, O
+and O
+high O
+energy O
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+
+
+However O
+, O
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+EBM S-MANP
+, O
+metal B-MATE
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+a O
+high-power O
+electron B-CONPRI
+beam E-CONPRI
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+
+
+When O
+making O
+a O
+lattice B-FEAT
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+certain O
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+remove O
+the O
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+lattice S-CONPRI
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+
+
+However O
+, O
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+powder-removing O
+hole O
+can O
+reduce O
+the O
+lattice S-CONPRI
+mechanical O
+performance S-CONPRI
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+
+
+We O
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+to O
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+large O
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+
+
+The O
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+the O
+EBM S-MANP
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+a O
+Ti–6Al–4V O
+alloy S-MATE
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+
+
+The O
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+83 O
+% O
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+the O
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+the O
+Hashin–Shtrikman O
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+approximate O
+20 O
+% O
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+the O
+experiments O
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+
+
+Selective B-MANP
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+( O
+SLM S-MANP
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+commonly O
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+( O
+AM S-MANP
+) O
+process S-CONPRI
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+
+
+Although O
+SLM S-MANP
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+near-net-shape S-MANP
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+this O
+process S-CONPRI
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+slower O
+compared O
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+alternative O
+metal S-MATE
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+. O
+
+
+A O
+higher O
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+rate E-PARA
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+SLM S-MANP
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+the O
+laser S-ENAT
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+velocity O
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+laser B-PARA
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+, O
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+in O
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+part O
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+the O
+SLM S-MANP
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+physical O
+limits S-CONPRI
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+
+
+This O
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+in O
+the O
+melt B-MATE
+pool E-MATE
+. O
+
+
+Single O
+bead S-CHAR
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+were O
+conducted O
+, O
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+the O
+thresholds O
+of O
+the O
+process B-CONPRI
+parameters E-CONPRI
+resulting O
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+voids S-CONPRI
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+identified O
+. O
+
+
+A O
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+ratio O
+of O
+0.85 O
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+critical O
+value O
+for O
+preventing O
+voids S-CONPRI
+in O
+the O
+process S-CONPRI
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+
+
+The O
+melt B-MATE
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+with O
+the O
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+the O
+normalized O
+enthalpy O
+and O
+the O
+volumetric O
+energy B-PARA
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+
+
+The O
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+values O
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+the O
+normalized O
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+voids S-CONPRI
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+the O
+beam B-PARA
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+
+
+Moreover O
+, O
+unstable O
+single O
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+plotted O
+as S-MATE
+a O
+function O
+of O
+the O
+beam B-PARA
+diameters E-PARA
+. O
+
+
+In O
+addition O
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+the O
+experiments O
+, O
+a O
+finite B-CONPRI
+element I-CONPRI
+analysis E-CONPRI
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+built O
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+a O
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+= O
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+W O
+, O
+velocity O
+= O
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+mm/s O
+, O
+and O
+beam B-PARA
+diameter E-PARA
+= O
+100–260 O
+μm O
+) O
+. O
+
+
+A O
+new O
+laser S-ENAT
+metal O
+desposition O
+process S-CONPRI
+based O
+on O
+an O
+inside-laser O
+coaxial O
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+reduced O
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+steel S-MATE
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+which O
+is O
+featured O
+with O
+fine O
+microstructure S-CONPRI
+and O
+excellent O
+mechanical B-CONPRI
+properties E-CONPRI
+. O
+
+
+In O
+addition O
+, O
+infrared S-CONPRI
+thermal O
+imaging S-APPL
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+and O
+Abaqus S-ENAT
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+simulation S-ENAT
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+conducted O
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+characterize O
+the O
+complex O
+thermal O
+history O
+during O
+the O
+laser B-MANP
+metal I-MANP
+deposition E-MANP
+process O
+. O
+
+
+The O
+microstructure S-CONPRI
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+mechanical B-CONPRI
+properties E-CONPRI
+of O
+reduced O
+activation O
+steel S-MATE
+were O
+systematically O
+investigated O
+in O
+the O
+as-fabricated O
+and O
+heat-treated S-MANP
+samples O
+. O
+
+
+The O
+results O
+indicat O
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+the O
+peak O
+temperature S-PARA
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+and O
+the O
+cooling B-PARA
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+the O
+melt B-MATE
+pool E-MATE
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+additional O
+layers O
+were O
+deposited O
+as S-MATE
+a O
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+
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+0.26 O
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+
+heat S-CONPRI
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+
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+
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+
+Next O
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+
+This O
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+
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+automatically O
+. O
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+
+The O
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+a O
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+
+This O
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+
+The O
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+
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+
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+
+It O
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+
+EDX-analyses O
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
+These O
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+
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+
+
+Building O
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+a O
+large O
+scale O
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+AM S-MANP
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+one O
+of O
+the O
+biggest O
+manufacturing S-MANP
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+our O
+time O
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+
+
+In O
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+decade O
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+the O
+proliferation O
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+engineers O
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+constructions O
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+be S-MATE
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+additively O
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+
+
+However O
+, O
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+
+In O
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+considered O
+not O
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+the O
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+material S-MATE
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+
+This O
+paper O
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+Fused B-MANP
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+the O
+most O
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+
+The O
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+design I-CONPRI
+algorithms E-CONPRI
+, O
+multi-criteria O
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+production S-MANP
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+
+The O
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+culminates O
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+efficiency O
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+
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+( O
+SLM S-MANP
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+in O
+an O
+argon S-MATE
+environment O
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+
+
+Conventionally O
+, O
+this O
+steel S-MATE
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+a O
+martensitic O
+structure S-CONPRI
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+small O
+fraction S-CONPRI
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+δ O
+ferrite S-MATE
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+
+However O
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+proved O
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+SLM-ed O
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+δ O
+ferrite S-MATE
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+
+
+The O
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+
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+to O
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+the O
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+
+
+Furthermore O
+, O
+the O
+energy-dispersive O
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+
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+
+It O
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+
+Electron B-MANP
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+
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+
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+
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+
+Bulk O
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+
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+
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+
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+
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+
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+
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+
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+consolidation S-CONPRI
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+DED S-MANP
+and O
+the O
+heat B-MANP
+treatment E-MANP
+of O
+the O
+compacts S-MATE
+. O
+
+
+First O
+mechanical B-CHAR
+tests E-CHAR
+demonstrate O
+the O
+high O
+hardness S-PRO
+and O
+the O
+competitive O
+creep S-PRO
+resistance O
+of O
+the O
+AM S-MANP
+V–9Si–5B O
+material S-MATE
+in O
+comparison O
+to O
+other O
+three-phase O
+V-based O
+alloys S-MATE
+. O
+
+
+Metal B-MANP
+additive I-MANP
+manufacturing E-MANP
+offers O
+a O
+tool S-MACEQ
+to O
+bring O
+formerly O
+unmanufacturable O
+, O
+geometrically O
+complex O
+, O
+engineered O
+structures O
+into O
+existence O
+. O
+
+
+However O
+, O
+considerable O
+challenges O
+remain O
+in O
+controlling O
+the O
+unique O
+microstructures S-MATE
+, O
+defects S-CONPRI
+and O
+properties S-CONPRI
+that O
+are O
+created O
+through O
+this O
+process S-CONPRI
+. O
+
+
+For O
+the O
+first O
+time O
+this O
+work O
+demonstrates O
+how O
+LaB6 O
+nanoparticles S-CONPRI
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+be S-MATE
+used O
+to O
+control O
+such O
+features O
+in O
+Al B-MATE
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+by O
+Selective B-MANP
+Laser I-MANP
+Melting E-MANP
+( O
+SLM S-MANP
+) O
+. O
+
+
+A O
+novel O
+and O
+efficient O
+mechanical S-APPL
+agitation S-CONPRI
+process O
+is O
+used O
+to O
+inoculate O
+AlSi10Mg S-MATE
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+with O
+LaB6 O
+nanoparticles S-CONPRI
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+resulted O
+in O
+a O
+homogenous O
+, O
+crack-free O
+, O
+equiaxed O
+, O
+very O
+fine-grained O
+as S-MATE
+built O
+microstructures S-MATE
+. O
+
+
+The O
+substantial O
+grain B-CHAR
+refinement E-CHAR
+is O
+attributed O
+to O
+the O
+good O
+crystallographic O
+atomic O
+matching O
+across O
+the O
+Al/LaB6 O
+interfaces O
+which O
+facilitated O
+Al S-MATE
+nucleation O
+on O
+the O
+LaB6 O
+nanoparticles S-CONPRI
+. O
+
+
+The O
+LaB6-inoculated O
+AlSi10Mg S-MATE
+exhibited O
+near-isotropic O
+mechanical B-CONPRI
+properties E-CONPRI
+with O
+an O
+improved O
+plasticity S-PRO
+compared O
+with O
+un O
+modified O
+AlSi10Mg S-MATE
+. O
+
+
+Selective B-MANP
+laser I-MANP
+melting E-MANP
+( O
+SLM S-MANP
+) O
+has O
+become O
+one O
+of O
+the O
+most O
+commonly O
+utilized O
+processes S-CONPRI
+in O
+metal B-MANP
+additive I-MANP
+manufacturing E-MANP
+( O
+AM S-MANP
+) O
+. O
+
+
+Despite O
+its O
+widespread O
+use O
+and O
+capabilities O
+, O
+SLM S-MANP
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+are O
+still O
+being O
+produced O
+with O
+excessive O
+volumetric O
+defects S-CONPRI
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+flaws S-CONPRI
+. O
+
+
+The O
+complex O
+dependence O
+of O
+defect S-CONPRI
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+process B-CONPRI
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+geometry S-CONPRI
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+material B-CONPRI
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+inhibited O
+effective O
+quality S-CONPRI
+assurance O
+in O
+SLM B-MANP
+production E-MANP
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+
+
+Exacerbating O
+these O
+issues O
+are O
+the O
+difficulties O
+thus O
+far O
+in O
+accurately S-CHAR
+detecting O
+and O
+identifying O
+defects S-CONPRI
+in-process O
+so O
+that O
+parts O
+may O
+be S-MATE
+qualified O
+without O
+destructive B-CHAR
+testing E-CHAR
+. O
+
+
+Some O
+of O
+the O
+most O
+detrimental O
+defects S-CONPRI
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+during O
+SLM S-MANP
+processing O
+are O
+lack O
+of O
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+LoF O
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+defects S-CONPRI
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+which O
+are O
+frequently O
+found O
+to O
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+excess O
+of O
+100 O
+μm O
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+size O
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+thus O
+these O
+defects S-CONPRI
+are O
+of O
+critical O
+importance O
+to O
+detect O
+and O
+remove O
+. O
+
+
+In O
+this O
+work O
+, O
+we O
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+developed O
+and O
+demonstrated O
+the O
+capabilities O
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+a O
+novel O
+in B-CONPRI
+situ E-CONPRI
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+system O
+using O
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+infrared S-CONPRI
+( O
+IR S-CHAR
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+thermography O
+to O
+monitor S-CONPRI
+AlSi10Mg S-MATE
+specimens O
+during O
+SLM B-MANP
+production E-MANP
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+
+
+Using O
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+relative O
+surface S-CONPRI
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+measurements O
+, O
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+transient S-CONPRI
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+, O
+which O
+supported O
+these O
+observations O
+. O
+
+
+Parts O
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+using O
+ex O
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+scanning B-CHAR
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+microscopy E-CHAR
+( O
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+data S-CONPRI
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+defects S-CONPRI
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+, O
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+, O
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+estimate O
+detection O
+success O
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+
+The O
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+effective O
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+identifying O
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+detection O
+success O
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+with O
+increasing O
+defect S-CONPRI
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+
+The O
+method O
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+also O
+used O
+statistically O
+to O
+analyze O
+the O
+presence O
+of O
+systematic O
+process B-CONPRI
+errors E-CONPRI
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+SLM B-MANP
+production E-MANP
+, O
+expanding O
+the O
+capabilities O
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+methods O
+. O
+
+
+This O
+unique O
+analysis O
+method O
+and O
+simple S-MANP
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+monitoring O
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+
+
+Additive B-MANP
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+doors O
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+efficient O
+fabrication S-MANP
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+functional O
+parts O
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+
+
+However O
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+( O
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+vulnerable O
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+generation O
+, O
+necessitating O
+the O
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+quality S-CONPRI
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+of O
+parts O
+. O
+
+
+An O
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+( O
+IMS O
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+on O
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+in-house O
+for O
+implementation O
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+the O
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+melting I-MANP
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+
+
+A O
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+single O
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+main O
+constituents O
+of O
+the O
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+
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+316 O
+L O
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+printed O
+with O
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+
+
+Features O
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+
+Micro O
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+capable O
+of O
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+recovering O
+the O
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+to O
+correlate O
+the O
+features O
+identified O
+in O
+the O
+optical S-CHAR
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+
+Results O
+have O
+shown O
+that O
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+indicator O
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+
+In O
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+years O
+, O
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+However O
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+
+Moreover O
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+the O
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+
+Hence O
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+
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+The O
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+
+
+Moreover O
+, O
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+surface S-CONPRI
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+
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+
+M B-ENAT
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+partial O
+columnar O
+to O
+equiaxed O
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+
+In O
+this O
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+laser B-MANP
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+high O
+strength S-PRO
+steel S-MATE
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+AHSS O
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+samples S-CONPRI
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+
+
+Different O
+L-PBF S-MANP
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+to O
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+, O
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+mechanical B-CONPRI
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+
+
+The O
+influence O
+of O
+build B-MACEQ
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+( O
+200 O
+°C–800 O
+°C O
+) O
+, O
+laser S-ENAT
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+( O
+550 O
+mm/s O
+- O
+950 O
+mm/s O
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+& O
+Sleep O
+( O
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+) O
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+
+Local O
+solidification B-CONPRI
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+the O
+melt B-MATE
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+
+cooling B-PARA
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+, O
+temperature B-PARA
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+FEM S-CONPRI
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+model S-CONPRI
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+the O
+solidification B-CONPRI
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+
+
+By O
+using O
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+analysis O
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+tensile B-CHAR
+testing E-CHAR
+, O
+the O
+mechanical B-CONPRI
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+the O
+AHSS O
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+by O
+considering O
+microstructural S-CONPRI
+aspects O
+. O
+
+
+It O
+was O
+found O
+that O
+AHSS O
+, O
+produced O
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+higher O
+laser S-ENAT
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+alternative O
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+revealed O
+a O
+reduced O
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+texture S-FEAT
+intensity O
+. O
+
+
+This O
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+partial O
+columnar O
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+equiaxed O
+transition S-CONPRI
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+CET O
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+increased O
+density S-PRO
+of O
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+
+Preheating S-MANP
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+the O
+build B-MACEQ
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+columnar B-PRO
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+low O
+dislocation B-PRO
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+and O
+reduced O
+yield B-PRO
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+
+The O
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+discussed O
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+on O
+fundamental O
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+
+The O
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+chain E-ENAT
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+this O
+method O
+starts O
+with O
+injection B-MANP
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+
+
+The O
+polymer S-MATE
+of O
+this O
+part O
+is O
+functionalized O
+with O
+LDS-additives O
+which O
+allow O
+the O
+part O
+to O
+be S-MATE
+laser O
+structured O
+subsequently O
+. O
+
+
+This O
+technique O
+is O
+less O
+suitable O
+for O
+prototypes S-CONPRI
+and O
+small-scale O
+productions O
+of O
+3D-MIDs O
+because O
+of O
+its O
+properties S-CONPRI
+. O
+
+
+Contrary O
+to O
+the O
+injection B-MANP
+molding E-MANP
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+, O
+the O
+additive B-MANP
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+AM S-MANP
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+, O
+such O
+as S-MATE
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+bed S-MACEQ
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+e.g O
+. O
+
+
+selective B-MANP
+laser I-MANP
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+SLS S-MANP
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+, O
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+a O
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+
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+, O
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+. O
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+PA2200 O
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+
+The O
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+A O
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+
+Once O
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+
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+
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+Higher O
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+Two O
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+
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+minimize O
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+
+In O
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+
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+The O
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+
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+
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+
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+
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+mullite S-MATE
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+
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+
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+
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+
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+
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+
+
+This O
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+to O
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+the O
+function O
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+the O
+printer S-MACEQ
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+ER70S-6 S-MATE
+steel O
+. O
+
+
+To O
+find O
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+printing O
+function O
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+the O
+smallest O
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+on O
+volume S-CONPRI
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+material S-MATE
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+, O
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+varied O
+to O
+provide O
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+the O
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+used O
+to O
+print S-MANP
+3-D S-CONPRI
+models O
+. O
+
+
+The O
+results O
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+3-D S-CONPRI
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+three O
+case B-CONPRI
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+increasing O
+geometric O
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+the O
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+presented O
+, O
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+show O
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+1 O
+mm S-MANP
+bead B-CHAR
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+. O
+
+
+In O
+the O
+current O
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+, O
+cylindrical S-CONPRI
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+AlSi10Mg B-MATE
+alloy E-MATE
+were O
+fabricated S-CONPRI
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+direct B-MANP
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+( O
+DMLS S-MANP
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+technique O
+in O
+vertical S-CONPRI
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+horizontal O
+directions O
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+
+
+The O
+microstructure S-CONPRI
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+the O
+samples S-CONPRI
+was O
+analyzed O
+using O
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+diffraction E-CHAR
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+electron I-CHAR
+microscopy E-CHAR
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+
+It O
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+observed O
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+in O
+the O
+alloy S-MATE
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+
+While O
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+the O
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+the O
+vertical B-CONPRI
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+columnar O
+, O
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+changing O
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+direction O
+to O
+horizontal O
+, O
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+the O
+grains S-CONPRI
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+with O
+columnar O
+shape O
+and O
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+of O
+them O
+were O
+equiaxed O
+. O
+
+
+Moreover O
+, O
+the O
+texture S-FEAT
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+DMLS-AlSi10Mg O
+alloy S-MATE
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+due O
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+CET O
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+
+While O
+{ O
+001 O
+} O
+fiber S-MATE
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+in O
+the O
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+the O
+horizontal O
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+
+Using O
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+of O
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+constitutional O
+undercooling O
+, O
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+. O
+
+
+It O
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+the O
+sample S-CONPRI
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+
+Further O
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+α-Al O
+dendrites S-BIOP
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+alloy S-MATE
+. O
+
+
+Metal B-MANP
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+manufacturing E-MANP
+, O
+despite O
+of O
+offering O
+unique O
+capabilities O
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+
+unlimited O
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+time O
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+etc. O
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+
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+
+To O
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+
+In O
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+
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+
+Also O
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+
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+
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+
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+
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+
+In O
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+
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+
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+
+X-ray B-CHAR
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+
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+
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+
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+
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+
+In O
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+
+Ballings O
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+
+It O
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+
+Ballings O
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+bulk O
+material S-MATE
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+
+
+Spatters O
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+
+Long O
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+
+Hybrid O
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+
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+
+The O
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+
+Various O
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+
+The O
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+
+All O
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+
+Microstructure S-CONPRI
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+both O
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+
+The O
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+840−940 O
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+
+The O
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+of O
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+hybrid O
+part O
+. O
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+
+In O
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+, O
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+selective B-MANP
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+melting E-MANP
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+stainless B-MATE
+steel E-MATE
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+a O
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+porous S-PRO
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+strongly O
+reduced O
+pore B-PARA
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+. O
+
+
+feature B-PARA
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+
+
+By O
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+be S-MATE
+generated O
+by O
+selectively O
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+powder B-MATE
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+
+
+A O
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+
+The O
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+( O
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+
+The O
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+on O
+characterization O
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+key O
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+
+The O
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+
+We O
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+
+
+For O
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+the O
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+
+Thermal B-PRO
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+
+
+The O
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+found O
+to O
+be S-MATE
+a O
+function O
+of O
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+
+
+Furthermore O
+, O
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+capillary O
+wicking O
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+steel S-MATE
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+9 O
+to O
+23 O
+µm O
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+
+Typically O
+, O
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+
+To O
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+
+This O
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+( O
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+
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+
+Simulation S-ENAT
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+
+Experimental S-CONPRI
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+wide O
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+many O
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+
+The O
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+
+Extrapolating O
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+functions O
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+
+Laser S-ENAT
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+
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+
+Results O
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+
+Continuous O
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+
+The O
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+
+Solidification S-CONPRI
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+( O
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+
+Results O
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+0.06 O
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+0.1 O
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+
+Electron O
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+
+The O
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+
+Metallization S-MANP
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+
+Here O
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+
+Fourier B-ENAT
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+The O
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+
+Additionally O
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+
+The O
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+
+Conversely O
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+
+Atmospheric O
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+
+Electron B-CHAR
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+termination O
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+
+The O
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+
+The O
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+
+Laser S-ENAT
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+
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+The O
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+
+Laser S-ENAT
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+a O
+fine O
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+Additionally O
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+powder S-MATE
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+the O
+outer O
+radius O
+in O
+a O
+“ O
+snow O
+plow O
+” O
+fashion S-CONPRI
+. O
+
+
+Encoder S-MACEQ
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+both O
+the O
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+stage O
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+galvanometers O
+assures O
+accuracy S-CHAR
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+the O
+laser B-ENAT
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+
+
+Build B-CHAR
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+
+
+The O
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+SLM S-MANP
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+. O
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+
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+( O
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+, O
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+
+The O
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+counterpart O
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+
+
+The O
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+] O
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+metallurgical S-APPL
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+0.1 O
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+
+Electrochemical B-CHAR
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+SLM S-MANP
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+more O
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+with O
+its O
+cast S-MANP
+counterpart O
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+
+
+It O
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+that O
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+a O
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+SLM S-MANP
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+
+
+It O
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+noted O
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+oxide S-MATE
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+are O
+mainly O
+sourced O
+by O
+powder S-MATE
+. O
+
+
+The O
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+that O
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+SLM S-MANP
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+Mg B-MATE
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+influence O
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+powder S-MATE
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+
+A O
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+of O
+40-layers O
+metal B-CONPRI
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+different O
+scanning B-CONPRI
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+
+
+The O
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+mechanical S-APPL
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+that O
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+
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+
+It O
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+that O
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+
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+
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+
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+
+A O
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+
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+
+The O
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+
+Results O
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+
+There O
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+
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+custom O
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+
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+
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+
+This O
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+
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+
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+
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+
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+
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+
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+
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+
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+
+Computed B-CHAR
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+
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+
+Three O
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+
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+
+With O
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+
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+
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+
+
+But O
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+
+Binder S-MATE
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+heat B-MANP
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+
+
+It O
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+
+
+The O
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+additive S-MATE
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+the O
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+
+The O
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+
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+We O
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+
+Then O
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+
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+
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+
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+powder S-MATE
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+
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+
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+
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+
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+
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+
+In O
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+CMBD O
+) O
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+
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+
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+This O
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+4 O
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+) O
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+Ti6Al4V S-MATE
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+, O
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+( O
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+) O
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+titanium-tantalum O
+alloy S-MATE
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+Ti-30Ta O
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+This O
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+reusability O
+of O
+steel B-MATE
+powder E-MATE
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+SLM S-MANP
+processing O
+was O
+investigated O
+. O
+
+
+The O
+results O
+indicated O
+that O
+multiple O
+reuse O
+is O
+possible O
+, O
+but O
+only O
+in O
+combination O
+with O
+powder S-MATE
+processing O
+( O
+mechanical S-APPL
+sieving O
+) O
+after O
+each O
+SLM S-MANP
+cycle O
+. O
+
+
+The O
+microstructure S-CONPRI
+of O
+SLM-densified O
+high-speed O
+steel S-MATE
+consists O
+of O
+a O
+cellular O
+, O
+fine O
+dendritic O
+subgrain O
+segregation S-CONPRI
+structure O
+( O
+submicro O
+level O
+) O
+that O
+is O
+not O
+significantly O
+affected O
+by O
+preheating S-MANP
+the O
+base O
+plate O
+. O
+
+
+The O
+mechanical S-APPL
+and O
+tribological B-CONPRI
+properties E-CONPRI
+were O
+examined O
+in O
+relation O
+to O
+the O
+manufacturing S-MANP
+technique O
+and O
+the O
+subsequent O
+heat B-MANP
+treatment E-MANP
+. O
+
+
+Our O
+investigations O
+revealed O
+promising O
+behavior O
+with O
+respect O
+to O
+hardness S-PRO
+tempering O
+( O
+position O
+of O
+the O
+secondary O
+hardness S-PRO
+peak O
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+and O
+tribology S-CONPRI
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+the O
+M3:2 O
+steel S-MATE
+processed S-CONPRI
+by O
+SLM S-MANP
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+to O
+the O
+HIP S-MANP
+and O
+cast S-MANP
+conditions O
+. O
+
+
+A O
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+made O
+of O
+two O
+materials S-CONPRI
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+fabricated S-CONPRI
+by O
+selective B-MANP
+laser I-MANP
+melting E-MANP
+( O
+SLM S-MANP
+) O
+of O
+AlSi10Mg S-MATE
+on O
+an O
+Al-Cu-Ni-Fe-Mg O
+cast S-MANP
+alloy S-MATE
+substrate O
+. O
+
+
+The O
+microstructure S-CONPRI
+of O
+the O
+two-material O
+component S-MACEQ
+and O
+the O
+interface S-CONPRI
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+using O
+multi-scale O
+characterization O
+techniques O
+including O
+optical B-CHAR
+microscopy E-CHAR
+( O
+OM S-CHAR
+) O
+, O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+SEM S-CHAR
+) O
+, O
+electron B-CHAR
+backscatter I-CHAR
+diffraction E-CHAR
+( O
+EBSD S-CHAR
+) O
+, O
+and O
+transmission B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+TEM S-CHAR
+) O
+. O
+
+
+The O
+microstructure S-CONPRI
+of O
+SLM-AlSi10Mg O
+consists O
+of O
+fine O
+cellular O
+dendrites S-BIOP
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+, O
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+along O
+the O
+building B-PARA
+direction E-PARA
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+where O
+the O
+substrate S-MATE
+cast S-MANP
+alloy S-MATE
+is O
+featured O
+by O
+large O
+equiaxed B-CONPRI
+grains E-CONPRI
+. O
+
+
+OM S-CHAR
+and O
+SEM S-CHAR
+studies O
+of O
+the O
+interface S-CONPRI
+show O
+a O
+sound O
+metallurgical B-CONPRI
+bonding E-CONPRI
+as S-MATE
+a O
+result O
+of O
+the O
+melting S-MANP
+of O
+AlSi10Mg S-MATE
+powder O
+and O
+partial O
+melting S-MANP
+of O
+the O
+cast S-MANP
+substrate O
+assisted O
+by O
+the O
+circulate O
+flows O
+and O
+Marangoni O
+convection O
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+
+
+The O
+circulate O
+flows O
+cause O
+complex O
+phenomena O
+at O
+the O
+interface S-CONPRI
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+which O
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+to O
+the O
+dilution O
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+alloying B-MATE
+elements E-MATE
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+a O
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+microstructure S-CONPRI
+of O
+the O
+first O
+consolidated O
+layer S-PARA
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+SLM-AlSi10Mg O
+( O
+as S-MATE
+a O
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+solidification B-PARA
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+) O
+. O
+
+
+TEM S-CHAR
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+segregation S-CONPRI
+of O
+alloying B-MATE
+elements E-MATE
+at O
+the O
+interdendritic O
+regions O
+after O
+solidification S-CONPRI
+. O
+
+
+Moreover O
+, O
+no O
+precipitate S-MATE
+is O
+formed O
+on O
+top O
+of O
+the O
+interface S-CONPRI
+, O
+due O
+to O
+the O
+rapid B-MANP
+solidification E-MANP
+and O
+dilution O
+of O
+the O
+alloying B-MATE
+elements E-MATE
+. O
+
+
+EBSD S-CHAR
+analysis O
+of O
+the O
+interface S-CONPRI
+shows O
+substantial O
+differences O
+in O
+the O
+grain B-CONPRI
+structure E-CONPRI
+of O
+SLM-AlSi10Mg O
+and O
+the O
+cast S-MANP
+substrate O
+, O
+in O
+terms O
+of O
+size O
+and O
+morphology S-CONPRI
+. O
+
+
+Mechanical B-CONPRI
+properties E-CONPRI
+of O
+the O
+hybrid O
+material S-MATE
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+studied O
+afterwards O
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+Vickers O
+microhardness S-CONPRI
+measurements O
+, O
+nanoindentation S-CHAR
+and O
+quasi-static S-CONPRI
+uniaxial O
+tensile B-CHAR
+tests E-CHAR
+. O
+
+
+The O
+SLM-AlSi10Mg O
+side O
+of O
+the O
+hybrid-part O
+possesses O
+better O
+performance S-CONPRI
+, O
+mainly O
+due O
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+its O
+finer O
+and O
+hierarchical O
+microstructure S-CONPRI
+. O
+
+
+Inkjet B-MANP
+printing E-MANP
+of O
+multiple O
+materials S-CONPRI
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+usually O
+processed S-CONPRI
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+multiple O
+steps O
+due O
+to O
+various O
+jetting S-MANP
+and O
+curing/sintering O
+conditions O
+. O
+
+
+The O
+ink S-MATE
+consists O
+of O
+iron B-MATE
+oxide E-MATE
+( O
+Fe3O4 S-MATE
+) O
+nanoparticles S-CONPRI
+( O
+nominal O
+particle S-CONPRI
+size O
+50–100 O
+nm O
+) O
+suspended O
+within O
+a O
+UV S-CONPRI
+curable O
+matrix O
+resin S-MATE
+. O
+
+
+The O
+viscosity S-PRO
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+surface B-PRO
+tension E-PRO
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+the O
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+form O
+a O
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+
+
+The O
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+of O
+the O
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+GHz O
+were O
+2.25 O
+, O
+2.73 O
+and O
+2.65 O
+F/m O
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+
+This O
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+form O
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+tunable O
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+
+A O
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+
+A O
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+extract O
+features O
+from O
+melt B-MATE
+pool E-MATE
+, O
+plume O
+and O
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+
+
+The O
+characteristics O
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+the O
+features O
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+melt B-MATE
+pool E-MATE
+, O
+plume O
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+investigated O
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+
+The O
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+the O
+extracted S-CONPRI
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+potential O
+indicators O
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+process S-CONPRI
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+
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+repeatability S-CONPRI
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+
+An O
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+
+A O
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+
+Kalman O
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+exact O
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+and O
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+the O
+melt B-MATE
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+frame O
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+
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+
+The O
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+
+The O
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+, O
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+
+It O
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+
+This O
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+an O
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+candidate O
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+the O
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+reactor O
+fuels O
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+
+The O
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+produce O
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+
+The O
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+
+The O
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+measured O
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+
+The O
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+
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+
+The O
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+
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+
+It O
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+
+Thus O
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+
+The O
+model S-CONPRI
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+into O
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+conduction O
+, O
+radiation S-MANP
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+
+A O
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+thermal O
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+user O
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+this O
+FE S-MATE
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+
+
+The O
+material S-MATE
+’ O
+s S-MATE
+thermal O
+behavior O
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+also O
+defined O
+via O
+the O
+subroutine O
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+
+As S-MATE
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+
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+
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+. O
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+
+Selective B-MANP
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+( O
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+
+
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+a O
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+in O
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+
+Based O
+on O
+this O
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+a O
+necessity O
+to O
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+warpage.In O
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+limited O
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+
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+in O
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+
+
+Therefore O
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+A O
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+
+A O
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+that O
+a O
+few O
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+below O
+the O
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+components S-MACEQ
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+by O
+LS O
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+of O
+complex B-CONPRI
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+a O
+layer-by-layer S-CONPRI
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+
+
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+in O
+the O
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+
+
+To O
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+optimization S-CONPRI
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+needed O
+so O
+that O
+the O
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+object O
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+the O
+pre-set O
+strength S-PRO
+and O
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+. O
+
+
+In O
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+article O
+a O
+material S-MATE
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+for O
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+bed S-MACEQ
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+or O
+selective B-MANP
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+sintered O
+( O
+SLS S-MANP
+) O
+PA12 S-MATE
+( O
+Nylon-12 O
+) O
+, O
+which O
+is O
+a O
+common O
+3D B-MANP
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+plastic O
+, O
+was O
+investigated O
+, O
+using O
+the O
+Finite B-CONPRI
+Element I-CONPRI
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+( O
+FEM S-CONPRI
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+. O
+
+
+The O
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+or O
+dog O
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+then O
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+to O
+simulate/predict O
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+mechanical S-APPL
+performance O
+of O
+the O
+SLS S-MANP
+printed O
+lower-leg O
+prosthesis O
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+, O
+pylon O
+and O
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+. O
+
+
+For O
+verification S-CONPRI
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+, O
+two O
+FEM S-CONPRI
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+a O
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+together O
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+specimens O
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+order O
+to O
+validate O
+the O
+used O
+Material S-MATE
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+
+
+The O
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+prosthesis O
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+tested O
+according O
+to O
+ISO S-MANS
+10328 O
+Standard S-CONPRI
+. O
+
+
+The O
+FEM S-CONPRI
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+, O
+together O
+with O
+the O
+Material S-MATE
+Model O
+, O
+was O
+found O
+to O
+give O
+good O
+estimations O
+for O
+the O
+location O
+of O
+a O
+failure S-CONPRI
+and O
+its O
+load O
+. O
+
+
+It O
+was O
+also O
+noted O
+that O
+there O
+were O
+significant O
+variations S-CONPRI
+among O
+individual O
+SLS S-MANP
+printed O
+test O
+specimens O
+, O
+which O
+impacted O
+on O
+the O
+material S-MATE
+parameters O
+and O
+the O
+FEM S-CONPRI
+simulations O
+. O
+
+
+Hence O
+, O
+to O
+enable O
+reliable O
+FEM S-CONPRI
+simulations O
+for O
+the O
+designing O
+of O
+3D B-MANP
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+products O
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+better O
+control O
+of O
+the O
+SLS B-MANP
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+regards O
+to O
+porosity S-PRO
+, O
+pore S-PRO
+morphology S-CONPRI
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+pore S-PRO
+distribution S-CONPRI
+is O
+needed O
+. O
+
+
+Water-atomized O
+and O
+gas-atomized O
+17-4 B-MATE
+PH I-MATE
+stainless I-MATE
+steel E-MATE
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+used O
+as S-MATE
+feedstock O
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+. O
+
+
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+single O
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+after O
+printing O
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+independent O
+of O
+energy B-PARA
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+
+
+As-printed O
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+dual O
+martensitic O
+and O
+austenitic S-MATE
+phase O
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+of O
+energy B-PARA
+density E-PARA
+. O
+
+
+The O
+H900 O
+heat B-MANP
+treatment E-MANP
+cycle O
+was O
+not O
+effective O
+in O
+enhancing O
+mechanical B-CONPRI
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+of O
+the O
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+powder S-MATE
+after O
+laser S-ENAT
+melting O
+. O
+
+
+However O
+, O
+after O
+solutionizing O
+at O
+1315ºC O
+and O
+aging O
+at O
+482 O
+°C O
+fully O
+martensitic O
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+was O
+observed O
+with O
+hardness S-PRO
+( O
+40.2 O
+HRC O
+) O
+, O
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+( O
+1000 O
+MPa S-CONPRI
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+ultimate B-PRO
+tensile I-PRO
+strength E-PRO
+( O
+1261 O
+MPa S-CONPRI
+) O
+comparable O
+to O
+those O
+of O
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+( O
+42.7 O
+HRC O
+, O
+1254 O
+MPa S-CONPRI
+and O
+1300 O
+MPa S-CONPRI
+) O
+and O
+wrought S-CONPRI
+alloy S-MATE
+( O
+39 O
+HRC O
+, O
+1170 O
+MPa S-CONPRI
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+1310 O
+MPa S-CONPRI
+) O
+, O
+respectively O
+. O
+
+
+Improved O
+mechanical B-CONPRI
+properties E-CONPRI
+in O
+water-atomized O
+powder S-MATE
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+found O
+to O
+be S-MATE
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+of O
+finer O
+martensite S-MATE
+and O
+higher O
+volume B-PARA
+fraction E-PARA
+of O
+fine O
+Cu-enriched O
+precipitates S-MATE
+. O
+
+
+Our O
+results O
+imply O
+that O
+water-atomized O
+powder S-MATE
+is O
+a O
+promising O
+cheaper O
+feedstock S-MATE
+alternative O
+to O
+gas-atomized O
+powder S-MATE
+. O
+
+
+Additive B-MANP
+manufacturing E-MANP
+( O
+AM S-MANP
+) O
+technologies S-CONPRI
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+new O
+processing O
+routes O
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+functionally B-MATE
+graded I-MATE
+materials E-MATE
+. O
+
+
+At O
+present O
+, O
+parts O
+built O
+using O
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+additional O
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+as S-MATE
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+
+
+A O
+difficulty O
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+
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+
+
+The O
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+
+Cutting B-CONPRI
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+a O
+mixture O
+of O
+CrB2 O
+and O
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+pure O
+Ti B-MATE
+powders E-MATE
+. O
+
+
+The O
+corresponding O
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+almost O
+fully B-PARA
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+suitable O
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+. O
+
+
+The O
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+diffraction E-CHAR
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+that O
+the O
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+a O
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+scanning B-PARA
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+the O
+laser B-CONPRI
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+
+The O
+parts O
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+at O
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+and O
+low O
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+, O
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+, O
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+. O
+
+
+The O
+wear S-CONPRI
+behavior O
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+compared O
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+pure O
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+parts O
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+
+Fused B-MANP
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+a O
+popular O
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+, O
+to O
+obtain O
+the O
+work B-MACEQ
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+
+
+A O
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+
+
+The O
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+
+
+This O
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+modify O
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+By O
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+
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+
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+
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+
+Consequently O
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+
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+
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+
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+
+The O
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+
+High O
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+Lower O
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+
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+
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+
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+
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+This O
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+
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+
+The O
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+against O
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+data S-CONPRI
+obtained O
+with O
+standard S-CONPRI
+specimen O
+geometries S-CONPRI
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+test O
+methods O
+. O
+
+
+The O
+present O
+methodology S-CONPRI
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+mini O
+specimens O
+under O
+cyclic O
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+efficiently O
+determines O
+the O
+fatigue S-PRO
+response O
+of O
+L-PBF S-MANP
+metals O
+. O
+
+
+Interlayer O
+bonds O
+pose O
+regions O
+of O
+weakness O
+in O
+structures O
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+via O
+melt B-MANP
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+polymer B-MANP
+additive I-MANP
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+. O
+
+
+Bond B-CONPRI
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+was O
+assessed O
+both O
+between O
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+layers O
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+tensile B-CHAR
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+ABS S-MATE
+coupons O
+printed O
+in O
+two O
+orientations S-CONPRI
+. O
+
+
+Print S-MANP
+parameters S-CONPRI
+considered O
+were O
+extruder S-MACEQ
+temperature O
+, O
+print S-MANP
+speed O
+, O
+and O
+layer B-PARA
+height E-PARA
+. O
+
+
+An O
+IR S-CHAR
+camera S-MACEQ
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+used O
+to O
+track O
+thermal O
+history O
+of O
+interlayer O
+bond O
+lines O
+during O
+the O
+printing B-MANP
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+. O
+
+
+Contact S-APPL
+length O
+between O
+roads O
+was O
+measured O
+from O
+mesostructure O
+optical S-CHAR
+micrographs O
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+
+
+Print S-MANP
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+have O
+a O
+large O
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+high O
+speeds O
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+
+A O
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+tensile B-PRO
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+length O
+greater O
+than O
+0.6 O
+independent O
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+print S-MANP
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+
+
+Laser B-MANP
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+( O
+LPBF S-MANP
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+is O
+a O
+popular O
+additive B-MANP
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+AM S-MANP
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+process S-CONPRI
+that O
+has O
+shown O
+promise O
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+novel O
+components S-MACEQ
+that O
+can O
+be S-MATE
+utilized O
+for O
+a O
+wide O
+variety O
+of O
+applications O
+. O
+
+
+However O
+, O
+one O
+of O
+the O
+main O
+drawbacks O
+of O
+LPBF S-MANP
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+that O
+it O
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+large O
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+during O
+the O
+solidification S-CONPRI
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+each O
+layer S-PARA
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+lead S-MATE
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+residual S-CONPRI
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+, O
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+resulting O
+in O
+build S-PARA
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+
+
+In O
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+, O
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+( O
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+method O
+, O
+and O
+laser S-ENAT
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+substrate S-MATE
+condition O
+) O
+on O
+residual B-PRO
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+and O
+distortion S-CONPRI
+. O
+
+
+X-ray B-CHAR
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+and O
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+measurements O
+were O
+performed O
+on O
+the O
+surfaces S-CONPRI
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+the O
+LPBF S-MANP
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+and O
+substrates O
+, O
+while O
+bulk O
+residual B-PRO
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+using O
+the O
+contour S-FEAT
+method O
+. O
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+
+In O
+addition O
+, O
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+line O
+profilometer S-MACEQ
+was O
+used O
+to O
+measure O
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+fabrication S-MANP
+. O
+
+
+The O
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+the O
+non-destructive O
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+destructive O
+measurement S-CHAR
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+that O
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+greatly O
+influence O
+the O
+development O
+of O
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+the O
+LPBF S-MANP
+deposit O
+and O
+the O
+substrate S-MATE
+. O
+
+
+Furthermore O
+, O
+the O
+experimental S-CONPRI
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+in O
+this O
+work O
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+a O
+valuable O
+foundation O
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+simulation S-ENAT
+of O
+the O
+evolution S-CONPRI
+of O
+residual B-PRO
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+
+
+Selective B-MANP
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+melting E-MANP
+( O
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+pursued O
+in O
+numerous O
+industries S-APPL
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+space O
+launch O
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+space O
+flight O
+. O
+
+
+In O
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+study O
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+performed O
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+extensive O
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+718 E-MATE
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+. O
+
+
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+both O
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+post-HIP O
+treated O
+states O
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+. O
+
+
+Tensile B-CHAR
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+
+
+It O
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+increases O
+in O
+porosity S-PRO
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+
+
+It O
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+while O
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+porosity S-PRO
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+the O
+laser S-ENAT
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+be S-MATE
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+clearest O
+indicator O
+of O
+build S-PARA
+quality O
+for O
+AM S-MANP
+processed O
+718 O
+. O
+
+
+Managing O
+the O
+dimensional B-CHAR
+accuracy E-CHAR
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+parts O
+produced O
+by O
+the O
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+is O
+a O
+challenge O
+. O
+
+
+For O
+small O
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+geometric O
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+linked O
+to O
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+
+The O
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+
+Simulating O
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+the O
+best O
+process B-CONPRI
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+accuracy S-CHAR
+. O
+
+
+The O
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+is O
+based O
+on O
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+. O
+
+
+Once O
+linked O
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+order O
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+trajectory O
+optimization S-CONPRI
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+
+First O
+, O
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+
+
+It O
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+determine O
+the O
+link O
+between O
+the O
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+current O
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+the O
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+
+
+Finally O
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+
+
+Additive B-MANP
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+, O
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+
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+, O
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+second O
+oldest O
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+
+In O
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+, O
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+. O
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+
+The O
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+. O
+
+
+Differences O
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+
+On O
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+in O
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+
+
+The O
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+
+Also O
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+direction O
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+specimens O
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+
+Finally O
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+
+An O
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+
+
+High O
+entropy O
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+to O
+test O
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+
+
+The O
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+metallic B-MATE
+materials E-MATE
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+
+
+Surface B-FEAT
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+
+
+Selective B-MANP
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+melting E-MANP
+( O
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+
+
+However O
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+exploring O
+new O
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+
+In O
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+relationship O
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+consumption O
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+SLM S-MANP
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+
+
+Several O
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+overlooked O
+factors O
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+including O
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+vaporization O
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+, O
+were O
+considered O
+to O
+improve O
+the O
+accuracy S-CHAR
+of O
+the O
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+
+
+Results O
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+that O
+, O
+to O
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+the O
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+by O
+the O
+local O
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+approximately O
+3–8 O
+times O
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+than O
+the O
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+consumption O
+( O
+Qc O
+) O
+, O
+and O
+this O
+finding O
+applies O
+to O
+all O
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+
+
+The O
+value O
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+
+Experiments O
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+high-entropy O
+alloy S-MATE
+( O
+CrMnFeCoNi O
+) O
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+Hastelloy S-MATE
+X O
+alloy S-MATE
+, O
+new O
+metallic B-MATE
+materials E-MATE
+for O
+SLM S-MANP
+, O
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+been O
+further O
+conducted O
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+
+Results O
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+
+This O
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+the O
+printing O
+substrate S-MATE
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+
+While O
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+
+A O
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+rubber E-MATE
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+
+Two O
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+a O
+rheometer O
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+
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+
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+
+Laser S-ENAT
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+
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+
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+
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+natural O
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+
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+
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+To O
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+
+The O
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+
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+
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+However O
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+The O
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+source S-APPL
+, O
+respectively O
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+
+When O
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+based I-MATE
+superalloys E-MATE
+, O
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+high O
+temperatures S-PARA
+( O
+approx O
+. O
+
+
+1000 O
+°C O
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+observed O
+in O
+the O
+powder B-MACEQ
+bed E-MACEQ
+, O
+base O
+plate O
+, O
+and O
+build S-PARA
+. O
+
+
+These O
+high O
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+, O
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+combined O
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+substrate S-MATE
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+, O
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+result O
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+final O
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+causing O
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+
+
+It O
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+the O
+thermo-mechanical S-CONPRI
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+the O
+entire O
+system O
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+to O
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+
+Therefore O
+, O
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+order O
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+optimum O
+component S-MACEQ
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+
+
+Such O
+a O
+comprehensive O
+computational O
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+to O
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+stress S-PRO
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+plastic S-MATE
+strain O
+accumulation O
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+the O
+material S-MATE
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+system O
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+different O
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+EBM S-MANP
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+
+Parts O
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+the O
+parent O
+material S-MATE
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+
+
+To O
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+of O
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+wave O
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+conducted O
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+
+For O
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+, O
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+
+
+The O
+main O
+properties S-CONPRI
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+material S-MATE
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+( O
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+
+Results O
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+about O
+2 O
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+0.1 O
+Hz–100 O
+Hz O
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+
+Droplet S-CONPRI
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+
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+
+
+Therefore O
+, O
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+
+Most O
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+the O
+study O
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+the O
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+
+The O
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+the O
+static O
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+the O
+images S-CONPRI
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+, O
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+
+Thus O
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+
+Instead O
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+paper O
+takes O
+the O
+video O
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+to O
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+the O
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+
+
+Compared O
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+most O
+of O
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+ground-truth O
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+
+Regarding O
+the O
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+the O
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+
+Experimental S-CONPRI
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+very O
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+
+Furthermore O
+, O
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+, O
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+
+
+Metallurgical B-CONPRI
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+
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+
+In O
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+powder S-MATE
+mixture O
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+
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+a O
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+
+The O
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+
+Focused O
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+
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+
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+
+The O
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+
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+While O
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+In O
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+RS O
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+the O
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+( O
+amount O
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+
+First O
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+that O
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+
+Second O
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+that O
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+play O
+an O
+eminent O
+role O
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+and O
+we O
+quantify O
+this O
+influence O
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+
+
+In O
+parallel O
+, O
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+X-ray B-CHAR
+Computed I-CHAR
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+
+3D-printed S-MANP
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+great O
+potential O
+in O
+the O
+aerospace S-APPL
+and O
+biomedical B-APPL
+industries E-APPL
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+
+
+However O
+, O
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+wide O
+application O
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+limited O
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+some O
+inherent O
+disadvantages O
+, O
+such O
+as S-MATE
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+finish E-FEAT
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+high O
+porosity S-PRO
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+
+
+In O
+this O
+study O
+, O
+an O
+innovative O
+method O
+, O
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+ultrasonic O
+nanocrystal O
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+to O
+process S-CONPRI
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+samples S-CONPRI
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+
+
+The O
+effect O
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+in-depth O
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+
+
+Compared O
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+
+
+Numerical O
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+
+This O
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+potentially O
+facilitate O
+pore S-PRO
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+under O
+ultrasonic O
+striking O
+. O
+
+
+Selective B-MANP
+laser I-MANP
+melting E-MANP
+( O
+SLM S-MANP
+) O
+technology S-CONPRI
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+a O
+layer-wise O
+powder-based B-MANP
+additive I-MANP
+manufacturing E-MANP
+method O
+capable O
+of O
+building O
+3D S-CONPRI
+components O
+from O
+their O
+CAD B-ENAT
+models E-ENAT
+. O
+
+
+This O
+approach O
+offers O
+enormous O
+benefits O
+for O
+generating O
+objects O
+with O
+geometrical B-FEAT
+complexity E-FEAT
+. O
+
+
+However O
+, O
+due O
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+the O
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+processing O
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+
+
+In O
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+study O
+, O
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+alloy S-MATE
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+
+All O
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+manufactured S-CONPRI
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+an O
+EOSINT O
+M O
+280 O
+machine S-MACEQ
+. O
+
+
+Laser B-PARA
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+, O
+scan B-PARA
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+a O
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+systematically O
+varied O
+to O
+understand O
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+effects O
+on O
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+
+
+The O
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+, O
+Ra O
+, O
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+. O
+
+
+The O
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+types O
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+surfaces S-CONPRI
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+. O
+
+
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+surfaces S-CONPRI
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+their O
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+influence O
+on O
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+
+
+Contour S-FEAT
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+skywriting O
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+strategies O
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+for O
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+the O
+surface B-PRO
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+. O
+
+
+Selective B-MANP
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+influence O
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+
+To O
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+
+On O
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+, O
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+want O
+the O
+process S-CONPRI
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+
+We O
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+the O
+powder B-MATE
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+
+
+In O
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+
+The O
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+
+From O
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+optimal O
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+which O
+the O
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+significantly O
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+few O
+degrees O
+. O
+
+
+Laser B-MANP
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+( O
+LENS™ O
+) O
+was O
+utilized O
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+( O
+SiO2 S-MATE
+) O
+coatings S-APPL
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+commercially-pure O
+titanium S-MATE
+( O
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+) O
+. O
+
+
+It O
+was O
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+silica S-MATE
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+be S-MATE
+deposited O
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+to O
+existing O
+Cp-Ti O
+material S-MATE
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+
+
+Post-deposition O
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+form O
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+( O
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+properties S-CONPRI
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+. O
+
+
+Titanium B-MATE
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+) O
+, O
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+( O
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+. O
+
+
+High O
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+1500 O
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+
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+
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+
+To O
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+
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+
+The O
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+
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+
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+
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+
+One O
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+
+It O
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+, O
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+
+It O
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+
+At O
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+
+For O
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+
+Through O
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+
+To O
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+
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+
+One O
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+
+This O
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+chamber O
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+
+The O
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+layers O
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+the O
+rotational O
+speed O
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+hardware O
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+
+
+These O
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+
+Example O
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+PLA S-MATE
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+Nylon S-MATE
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+
+In O
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+conductive O
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+PLA S-MATE
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+resistance S-PRO
+values O
+were O
+measured O
+across O
+the O
+resulting O
+printed O
+specimens O
+. O
+
+
+SLM S-MANP
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+Al-Mg-Sc-Zr O
+alloy S-MATE
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+structure E-CONPRI
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+
+
+A O
+good O
+strength-ductility O
+synergy O
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+zone O
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+
+In O
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+
+Flow O
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+
+Filament S-MATE
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+
+The O
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+
+The O
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+
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+influence O
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+
+In O
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+
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+
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+, O
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+EBSD S-CHAR
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+, O
+and O
+micro-hardness O
+measurements O
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+
+SEM S-CHAR
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+
+The O
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+nickel-based B-MATE
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+, O
+therefore O
+, O
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+
+Neutron B-CHAR
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+) O
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+ingredient O
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+, O
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+reported O
+. O
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+
+Both O
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+not O
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+in O
+the O
+ingredient O
+powder B-MATE
+particles E-MATE
+. O
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+
+In O
+addition O
+, O
+the O
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+
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+
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+LPBF S-MANP
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+
+Intergranular O
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+
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+intergranular O
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+
+In O
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+the O
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+
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+
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+
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+the O
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+
+
+Heat-treated S-MANP
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+improved O
+creep S-PRO
+lifetime O
+. O
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+
+The O
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+, O
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+
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+the O
+adoption O
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+this O
+process S-CONPRI
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+
+
+These O
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+
+In O
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+to O
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+
+A O
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+determine O
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+
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+precision S-CHAR
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+
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+Subsequent O
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+commercial O
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+In-situ S-CONPRI
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+issue O
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+In O
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+The O
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+development O
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+the O
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+lack O
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+A O
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+a O
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+mm3 O
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+roughly O
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+160 O
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+, O
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+
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+
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+
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+The O
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+
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+
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+( O
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+SLM S-MANP
+technology O
+. O
+
+
+Mechanical B-CHAR
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+that O
+components S-MACEQ
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+low O
+level O
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+
+Subsequent O
+heat B-MANP
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+
+
+However O
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+
+In O
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+subjected O
+to O
+three O
+different O
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+procedures O
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+
+
+The O
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+
+The O
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+
+The O
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+
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+
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+coefficients E-PRO
+of O
+parts O
+produced O
+were O
+quantified O
+. O
+
+
+Process S-CONPRI
+window O
+was O
+determined O
+for O
+Invar S-MATE
+36 O
+and O
+stainless B-MATE
+steel E-MATE
+316 O
+L O
+based O
+on O
+stable O
+melting S-MANP
+. O
+
+
+This O
+paper O
+presents O
+an O
+experimental S-CONPRI
+study O
+on O
+the O
+metallurgical S-APPL
+issues O
+associated O
+with O
+selective B-MANP
+laser I-MANP
+melting E-MANP
+of O
+Invar S-MATE
+36 O
+and O
+stainless B-MATE
+steel E-MATE
+316 O
+L O
+and O
+the O
+resulting O
+coefficient B-PRO
+of I-PRO
+thermal I-PRO
+expansion E-PRO
+. O
+
+
+Invar S-MATE
+36 O
+has O
+been O
+used O
+in O
+aircraft O
+control B-MACEQ
+systems E-MACEQ
+, O
+electronic O
+devices O
+, O
+optical S-CHAR
+instruments O
+, O
+and O
+medical S-APPL
+instruments O
+that O
+are O
+exposed O
+to O
+significant O
+temperature S-PARA
+changes O
+. O
+
+
+Stainless B-MATE
+steel E-MATE
+316 O
+L O
+is O
+commonly O
+used O
+for O
+applications O
+that O
+require O
+high O
+corrosion B-CONPRI
+resistance E-CONPRI
+in O
+the O
+aerospace S-APPL
+, O
+medical S-APPL
+, O
+and O
+nuclear O
+industries S-APPL
+. O
+
+
+Both O
+Invar S-MATE
+36 O
+and O
+stainless B-MATE
+steel E-MATE
+316 O
+L O
+are O
+weldable O
+austenitic S-MATE
+face-centered O
+cubic O
+crystal B-PRO
+structures E-PRO
+, O
+but O
+stainless B-MATE
+steel E-MATE
+316 O
+L O
+may O
+experience O
+chromium S-MATE
+evaporation O
+and O
+Invar S-MATE
+36 O
+may O
+experience O
+weld S-FEAT
+cracking S-CONPRI
+during O
+the O
+welding S-MANP
+process S-CONPRI
+. O
+
+
+Various O
+laser S-ENAT
+process O
+parameters S-CONPRI
+were O
+tested O
+based O
+on O
+a O
+full O
+factorial B-CONPRI
+design E-CONPRI
+of O
+experiments O
+. O
+
+
+The O
+microstructure S-CONPRI
+, O
+material S-MATE
+composition S-CONPRI
+, O
+coefficient B-PRO
+of I-PRO
+thermal I-PRO
+expansion E-PRO
+, O
+and O
+magnetic O
+dipole O
+moment O
+were O
+measured O
+for O
+both O
+materials S-CONPRI
+. O
+
+
+It O
+was O
+found O
+that O
+there O
+exists O
+a O
+critical O
+laser B-PARA
+energy I-PARA
+density E-PARA
+for O
+each O
+material S-MATE
+, O
+EC O
+, O
+for O
+which O
+selective B-MANP
+laser I-MANP
+melting I-MANP
+process E-MANP
+is O
+optimal O
+for O
+material B-CONPRI
+properties E-CONPRI
+. O
+
+
+The O
+critical O
+laser B-PARA
+energy I-PARA
+density E-PARA
+provides O
+enough O
+energy O
+to O
+induce O
+stable O
+melting S-MANP
+, O
+homogeneous S-CONPRI
+microstructure O
+and O
+chemical B-CONPRI
+composition E-CONPRI
+, O
+resulting O
+in O
+thermal B-CONPRI
+expansion E-CONPRI
+and O
+magnetic O
+properties S-CONPRI
+in O
+line O
+with O
+that O
+expected O
+for O
+the O
+wrought B-MATE
+material E-MATE
+. O
+
+
+Below O
+the O
+critical O
+energy O
+, O
+a O
+lack O
+of O
+fusion S-CONPRI
+due O
+to O
+insufficient O
+melt S-CONPRI
+tracks O
+and O
+discontinuous O
+beads S-CHAR
+was O
+observed O
+. O
+
+
+The O
+melt S-CONPRI
+track O
+was O
+also O
+unstable O
+above O
+the O
+critical O
+energy O
+due O
+to O
+vaporization O
+and O
+microsegregation S-CONPRI
+of O
+alloying B-MATE
+elements E-MATE
+. O
+
+
+Both O
+cases O
+can O
+generate O
+stress S-PRO
+risers S-MACEQ
+and O
+part O
+flaws S-CONPRI
+during O
+manufacturing S-MANP
+. O
+
+
+These O
+flaws S-CONPRI
+could O
+be S-MATE
+avoided O
+by O
+finding O
+the O
+critical O
+laser B-CONPRI
+energy E-CONPRI
+needed O
+for O
+each O
+material S-MATE
+. O
+
+
+The O
+critical O
+laser B-PARA
+energy I-PARA
+density E-PARA
+was O
+determined O
+to O
+be S-MATE
+86.8 O
+J/mm3 O
+for O
+Invar S-MATE
+36 O
+and O
+104.2 O
+J/mm3 O
+for O
+stainless B-MATE
+steel E-MATE
+316 O
+L. O
+The O
+present O
+study O
+investigated O
+the O
+effects O
+of O
+set S-APPL
+radius O
+of O
+curvature O
+and O
+fiber B-MATE
+bundle E-MATE
+size O
+on O
+the O
+precision S-CHAR
+of O
+the O
+radius O
+of O
+curvature O
+during O
+continuous B-MATE
+carbon I-MATE
+fiber E-MATE
+three-dimensional O
+( O
+3D S-CONPRI
+) O
+printing O
+. O
+
+
+First O
+, O
+individual O
+circles O
+with O
+various O
+radii O
+using O
+various O
+sizes O
+of O
+fiber B-MATE
+bundles E-MATE
+were O
+printed O
+with O
+a O
+3D B-MACEQ
+printer E-MACEQ
+. O
+
+
+It O
+was O
+demonstrated O
+that O
+with O
+a O
+larger O
+fiber B-MATE
+bundle E-MATE
+size O
+or O
+a O
+smaller O
+set S-APPL
+radius O
+, O
+the O
+printed O
+radius O
+would O
+be S-MATE
+lower O
+than O
+the O
+set S-APPL
+value O
+. O
+
+
+Equiatomic O
+CoCrFeMnNi O
+HEA O
+was O
+successfully O
+fabricated S-CONPRI
+by O
+SLM S-MANP
+. O
+
+
+The O
+XRD S-CHAR
+profiles S-FEAT
+of O
+the O
+SLM-CoCrFeMnNi O
+HEA O
+were O
+refined O
+by O
+the O
+Rietveld O
+program O
+. O
+
+
+The O
+effect O
+of O
+the O
+peak O
+load O
+on O
+the O
+creep S-PRO
+deformation O
+was O
+investigated O
+by O
+nanoindentation S-CHAR
+with O
+a O
+Berkovich B-CHAR
+indenter E-CHAR
+. O
+
+
+The O
+creep S-PRO
+was O
+mainly O
+dominated O
+by O
+deformation S-CONPRI
+controlled O
+by O
+dislocation B-CONPRI
+motion E-CONPRI
+. O
+
+
+Selective B-MANP
+laser I-MANP
+melting E-MANP
+( O
+SLM S-MANP
+) O
+was O
+used O
+to O
+fabricate S-MANP
+an O
+equiatomic O
+CoCrFeMnNi O
+high-entropy O
+alloy S-MATE
+( O
+HEA O
+) O
+. O
+
+
+The O
+SLM-fabricated O
+CoCrFeMnNi O
+HEA O
+samples S-CONPRI
+were O
+studied O
+with O
+X-ray B-CHAR
+diffraction E-CHAR
+( O
+XRD S-CHAR
+) O
+, O
+field-emission O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+( O
+FESEM S-CHAR
+) O
+, O
+electron B-CHAR
+backscatter I-CHAR
+diffraction E-CHAR
+( O
+EBSD S-CHAR
+) O
+and O
+nanoindentation S-CHAR
+techniques O
+to O
+characterize O
+the O
+microstructure S-CONPRI
+and O
+creep B-PRO
+behavior E-PRO
+. O
+
+
+It O
+was O
+found O
+that O
+the O
+HEA O
+comprised O
+a O
+single O
+face-centered O
+cubic O
+( O
+fcc S-CONPRI
+) O
+structure S-CONPRI
+. O
+
+
+Due O
+to O
+the O
+fast O
+solidification S-CONPRI
+and O
+high O
+temperature B-PARA
+gradients E-PARA
+of O
+the O
+molten B-CONPRI
+pool E-CONPRI
+during O
+the O
+SLM S-MANP
+process S-CONPRI
+, O
+the O
+microstructure S-CONPRI
+comprised O
+cellular O
+subgrains S-CONPRI
+with O
+grain B-CONPRI
+boundary E-CONPRI
+angles O
+lower O
+than O
+5° O
+. O
+
+
+Moreover O
+, O
+the O
+effect O
+of O
+the O
+peak O
+holding O
+load O
+on O
+the O
+nanoindentation S-CHAR
+creep S-PRO
+deformation O
+of O
+the O
+SLM-fabricated O
+HEA O
+was O
+investigated O
+using O
+a O
+Berkovich B-CHAR
+indenter E-CHAR
+. O
+
+
+The O
+results O
+of O
+this O
+study O
+indicated O
+that O
+the O
+creep S-PRO
+was O
+mainly O
+dominated O
+by O
+deformation S-CONPRI
+controlled O
+by O
+dislocation B-CONPRI
+motion E-CONPRI
+. O
+
+
+Spatter S-CHAR
+distribution S-CONPRI
+on O
+AlSi10Mg S-MATE
+powder O
+bed S-MACEQ
+was O
+quantified O
+in O
+terms O
+of O
+mass O
+, O
+size O
+and O
+processed B-CONPRI
+images E-CONPRI
+. O
+
+
+Established O
+vision O
+methodology S-CONPRI
+showed O
+moderate O
+positive O
+relationship O
+with O
+quantified O
+mass O
+of O
+spatter S-CHAR
+. O
+
+
+Spatter S-CHAR
+mass O
+and O
+size O
+distributions S-CONPRI
+could O
+serve O
+as S-MATE
+ground O
+truth O
+validation B-CONPRI
+data E-CONPRI
+for O
+future O
+simulation S-ENAT
+studies O
+. O
+
+
+Exponential O
+decay O
+in O
+the O
+Stk O
+number O
+with O
+respect O
+to O
+the O
+distance O
+travelled O
+by O
+the O
+spatter S-CHAR
+particles S-CONPRI
+. O
+
+
+In O
+Selective B-MANP
+Laser I-MANP
+Melting E-MANP
+( O
+SLM S-MANP
+) O
+, O
+inert B-CONPRI
+gas E-CONPRI
+is O
+pumped O
+into O
+the O
+chamber O
+to O
+eliminate O
+the O
+deleterious O
+by-products O
+, O
+which O
+includes O
+spatter S-CHAR
+. O
+
+
+Despite O
+this O
+, O
+traces O
+of O
+spatter S-CHAR
+on O
+the O
+powder B-MACEQ
+bed E-MACEQ
+have O
+always O
+been O
+observed O
+. O
+
+
+Earlier O
+research S-CONPRI
+mainly O
+focussed O
+on O
+the O
+formation O
+and O
+characterization O
+of O
+spatter S-CHAR
+particles S-CONPRI
+that O
+were O
+freshly O
+ejected O
+from O
+the O
+melt B-MATE
+pool E-MATE
+. O
+
+
+However O
+, O
+in O
+this O
+study O
+, O
+the O
+quantification O
+of O
+the O
+spatter S-CHAR
+distribution S-CONPRI
+on O
+the O
+powder B-MACEQ
+bed E-MACEQ
+was O
+performed O
+, O
+following O
+their O
+transport S-CHAR
+by O
+the O
+inert B-CONPRI
+gas E-CONPRI
+flow O
+which O
+was O
+varied O
+at O
+two O
+gas S-CONPRI
+pump O
+settings O
+( O
+60 O
+and O
+67 O
+% O
+) O
+. O
+
+
+Image S-CONPRI
+processing O
+for O
+spatter S-CHAR
+detection O
+based O
+on O
+contrast O
+was O
+first O
+conducted O
+. O
+
+
+The O
+sieved O
+out O
+spatter S-CHAR
+particles S-CONPRI
+were O
+quantified O
+by O
+precision S-CHAR
+weighing O
+of O
+mass O
+. O
+
+
+Optical B-CHAR
+microscopy E-CHAR
+was O
+then O
+utilised O
+for O
+size O
+determination O
+. O
+
+
+The O
+majority O
+of O
+spatter S-CHAR
+particles S-CONPRI
+were O
+originally O
+distributed O
+along O
+the O
+−x O
+direction O
+, O
+as S-MATE
+observed O
+from O
+the O
+top O
+down O
+images S-CONPRI
+taken O
+. O
+
+
+However O
+, O
+increasing O
+the O
+gas S-CONPRI
+flow O
+velocity O
+did O
+not O
+correspond O
+to O
+a O
+lesser O
+mass O
+distribution S-CONPRI
+. O
+
+
+Computations O
+on O
+the O
+Stk O
+number O
+revealed O
+that O
+at O
+the O
+gas S-CONPRI
+pump O
+setting O
+of O
+67 O
+% O
+, O
+spatter S-CHAR
+particles S-CONPRI
+of O
+greater O
+size O
+were O
+deposited O
+earlier O
+on O
+the O
+powder B-MACEQ
+bed E-MACEQ
+, O
+suggesting O
+that O
+increasing O
+the O
+gas S-CONPRI
+flow O
+velocity O
+to O
+a O
+large O
+extent O
+would O
+increase O
+the O
+likelihood O
+of O
+powder B-MACEQ
+bed E-MACEQ
+contamination O
+. O
+
+
+The O
+forward O
+extrapolation O
+of O
+the O
+exponential O
+Stk O
+number O
+trendlines O
+also O
+elucidated O
+the O
+reason O
+for O
+the O
+limitations O
+on O
+the O
+width O
+of O
+the O
+powder B-MACEQ
+bed E-MACEQ
+in O
+machines S-MACEQ
+designed S-FEAT
+by O
+SLM S-MANP
+Solutions O
+. O
+
+
+Bulk O
+high O
+strength S-PRO
+and O
+thermally O
+stable O
+Al85Nd8Ni5Co2 O
+samples S-CONPRI
+have O
+been O
+prepared O
+by O
+selective B-MANP
+laser I-MANP
+melting E-MANP
+( O
+SLM S-MANP
+) O
+. O
+
+
+The O
+alloy S-MATE
+shows O
+a O
+composite-like O
+microstructure S-CONPRI
+consisting O
+of O
+submicron-sized O
+stable O
+intermetallic S-MATE
+phases O
+dispersed O
+in O
+an O
+Al S-MATE
+matrix O
+, O
+which O
+leads O
+to O
+high O
+compressive B-PRO
+strength E-PRO
+( O
+1–0.5 O
+GPa S-PRO
+) O
+at O
+elevated O
+temperatures S-PARA
+( O
+303–573 O
+K S-MATE
+) O
+. O
+
+
+These O
+results O
+indicate O
+that O
+SLM S-MANP
+is O
+an O
+effective O
+alternative O
+to O
+conventional O
+routes O
+for O
+producing O
+dense O
+, O
+thermally O
+stable O
+and O
+near O
+net O
+shaped O
+components S-MACEQ
+from O
+high O
+strength S-PRO
+Al-based O
+alloys S-MATE
+. O
+
+
+In O
+this O
+study O
+, O
+novel O
+biomedical S-APPL
+Co29Cr9W3Cu O
+samples S-CONPRI
+were O
+fabricated S-CONPRI
+using O
+selective B-MANP
+laser I-MANP
+melting E-MANP
+( O
+SLM S-MANP
+) O
+technology S-CONPRI
+. O
+
+
+In O
+order O
+to O
+better O
+understand O
+the O
+formation O
+of O
+the O
+lattice B-CONPRI
+defects E-CONPRI
+during O
+the O
+melting S-MANP
+process O
+, O
+and O
+the O
+tensile S-PRO
+deformation S-CONPRI
+mechanism O
+of O
+the O
+SLM-produced O
+Co29Cr9W3Cu O
+samples S-CONPRI
+, O
+the O
+microstructures S-MATE
+of O
+the O
+samples S-CONPRI
+before O
+and O
+after O
+tensile S-PRO
+deformation S-CONPRI
+were O
+observed O
+using O
+a O
+scanning B-MACEQ
+electron I-MACEQ
+microscope E-MACEQ
+( O
+SEM S-CHAR
+) O
+, O
+a O
+transmission B-CHAR
+electron I-CHAR
+microscope E-CHAR
+( O
+TEM S-CHAR
+) O
+, O
+and O
+an O
+electron O
+back-scattered O
+diffraction S-CHAR
+( O
+EBSD S-CHAR
+) O
+, O
+respectively O
+. O
+
+
+The O
+SEM S-CHAR
+morphology S-CONPRI
+indicated O
+that O
+the O
+non-equilibrium O
+structure S-CONPRI
+of O
+the O
+SLM-produced O
+Co29Cr9W3Cu O
+samples S-CONPRI
+contained O
+cellular O
+and O
+columnar O
+subgrains S-CONPRI
+. O
+
+
+The O
+TEM S-CHAR
+observation O
+and O
+EBSD S-CHAR
+analysis O
+showed O
+that O
+the O
+accumulated O
+residual B-PRO
+stress E-PRO
+during O
+the O
+SLM S-MANP
+process S-CONPRI
+predominated O
+in O
+the O
+overlapping O
+regions O
+between O
+the O
+adjacent O
+scanning S-CONPRI
+tracks O
+, O
+which O
+consequently O
+induced O
+a O
+larger O
+number O
+of O
+the O
+lattice B-CONPRI
+defects E-CONPRI
+, O
+such O
+as S-MATE
+dislocations O
+and O
+overlapping O
+stacking O
+faults O
+. O
+
+
+The O
+analysis O
+of O
+the O
+tensile S-PRO
+deformation S-CONPRI
+revealed O
+that O
+the O
+main O
+plastic B-PRO
+deformation E-PRO
+was O
+caused O
+by O
+the O
+strain-induced O
+martensitic O
+transformation O
+effect O
+in O
+the O
+SLM-produced O
+Co29Cr9W3Cu O
+samples S-CONPRI
+. O
+
+
+Alumina/aluminum O
+titanate O
+composites S-MATE
+were O
+prepared O
+using O
+directed O
+laser S-ENAT
+deposition S-CONPRI
+. O
+
+
+Scanning B-PARA
+speed E-PARA
+has O
+a O
+significant O
+effect O
+on O
+the O
+microstructure S-CONPRI
+and O
+macro S-FEAT
+features O
+. O
+
+
+Microstructure S-CONPRI
+and O
+macro S-FEAT
+defects S-CONPRI
+are O
+responsible O
+for O
+the O
+trend S-CONPRI
+of O
+properties S-CONPRI
+. O
+
+
+Optimal O
+forming S-MANP
+quality O
+was O
+achieved O
+at O
+the O
+medium-speed O
+scanning B-CONPRI
+process E-CONPRI
+window O
+. O
+
+
+Directed B-MANP
+energy I-MANP
+deposition E-MANP
+( O
+DED S-MANP
+) O
+has O
+developed O
+rapidly O
+in O
+recent O
+years O
+as S-MATE
+a O
+new O
+material-structure O
+integration O
+manufacturing B-MANP
+technology E-MANP
+for O
+preparing O
+melt-growth O
+ceramics S-MATE
+. O
+
+
+However O
+, O
+the O
+influence O
+of O
+process S-CONPRI
+conditions O
+on O
+the O
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+
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+
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+
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+
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+
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+
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+
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+
+Generally O
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+
+Within O
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
+In O
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+
+Powder-liquid-solid O
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+
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+
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+
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+
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+
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+
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+
+Additionally O
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+The O
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+
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+
+The O
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
+The O
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+
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+
+In O
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+
+The O
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+
+During O
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+
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+
+The O
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+
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+
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+
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+
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+
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+
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+
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+
+An O
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+This O
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+SLM S-MANP
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+
+This O
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+Selective B-MANP
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+
+The O
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+
+Electron B-CHAR
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+
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+. O
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+
+Retained B-MATE
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+the O
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+
+EBSD S-CHAR
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+along O
+with O
+thermodynamic O
+equilibrium S-CONPRI
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+that O
+a O
+lower O
+Creq/Nieq O
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+resulting O
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+a O
+less O
+retained O
+δ O
+ferrite S-MATE
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+as-built O
+condition O
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+
+The O
+microstructure S-CONPRI
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+LAMed O
+300 O
+M O
+steel S-MATE
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+forgings O
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+
+
+Heat B-PRO
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+as-deposited O
+microstructure S-CONPRI
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+LAMed O
+300 O
+M O
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+
+After O
+heat B-MANP
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+microstructure S-CONPRI
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+LAMed O
+300 O
+M O
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+refined O
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+uniform O
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+
+
+After O
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+impact S-CONPRI
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+of O
+LAMed O
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+M O
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+improved O
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+
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+
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+
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+similar O
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+a O
+copper S-MATE
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+trace O
+at O
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+MHz O
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+
+Dual O
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+
+These O
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+capacitors S-APPL
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+conventional O
+counterparts O
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+
+
+The O
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+low O
+impedance O
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+copper-based O
+filament S-MATE
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+coil O
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+
+We O
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+
+This O
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+either O
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+fully-printed O
+electronic O
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+
+
+The O
+aim O
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+FDM S-MANP
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+
+The O
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+, O
+0° O
+, O
+0/90° O
+, O
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+90° O
+. O
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+
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+creating O
+stronger O
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+more O
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+various O
+applications O
+. O
+
+
+Parameters S-CONPRI
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+as S-MATE
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+varying O
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+ABS S-MATE
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+. O
+
+
+The O
+ABS-M30 O
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+exhibit O
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+mechanical B-CONPRI
+response E-CONPRI
+when O
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+to O
+axial O
+tensile S-PRO
+loading O
+. O
+
+
+The O
+stress-strain O
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+by O
+a O
+monotonic O
+increase O
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+an O
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+brittle B-CONPRI
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+
+
+In O
+certain O
+combinations O
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+raster B-PARA
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+slight O
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+. O
+
+
+The O
+tensile B-PRO
+strength E-PRO
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+, O
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+elongation-at-break O
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+found O
+to O
+be S-MATE
+highly O
+dependent O
+upon O
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+
+
+The O
+relationship O
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+mechanical B-CONPRI
+properties E-CONPRI
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+fractographic B-CHAR
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+
+
+The O
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+insight O
+and O
+provides O
+valuable O
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+the O
+purpose O
+of O
+building O
+structures O
+in O
+orientations S-CONPRI
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+to O
+their O
+exemplified O
+strength S-PRO
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+
+
+Other O
+examples O
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+shown O
+where O
+artifacts O
+of O
+the O
+FDM B-MANP
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+to O
+enhance O
+tensile B-PRO
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+configured O
+properly O
+with O
+respect O
+to O
+the O
+load O
+. O
+
+
+The O
+study O
+also O
+presents O
+a O
+systematic O
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+to O
+traditional O
+fiber-reinforced O
+polymer B-MATE
+composites E-MATE
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+of O
+build B-PARA
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+raster B-PARA
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+
+
+The O
+dissolution O
+kinetics O
+of O
+Laves B-CONPRI
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+been O
+analyzed O
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+
+
+The O
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+Inconel B-MATE
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+morphology S-CONPRI
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+the O
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+of O
+the O
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+deleterious O
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+beneficial O
+. O
+
+
+In O
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+post-heat O
+treatment O
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+to O
+regulate O
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+
+The O
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+
+The O
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+also O
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+
+
+The O
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+Nb S-MATE
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+
+Directed B-MANP
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+
+A O
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+
+
+The O
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+both O
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+extremely O
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+
+Samples S-CONPRI
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+
+A O
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+reported O
+. O
+
+
+Laser-Directed O
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+used O
+to O
+produce O
+AISI O
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+
+
+The O
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+parts O
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+
+The O
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+microscopy E-CHAR
+. O
+
+
+Only O
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+samples S-CONPRI
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+under O
+different O
+protective O
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+conditions O
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+
+
+However O
+, O
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+it O
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+that O
+the O
+protective O
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+affects O
+the O
+oxides S-MATE
+dimensions S-FEAT
+. O
+
+
+The O
+effect O
+of O
+the O
+oxides S-MATE
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+nitrogen S-MATE
+pick-up O
+on O
+the O
+mechanical S-APPL
+performance O
+of O
+the O
+samples S-CONPRI
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+evaluated O
+by O
+tensile B-CHAR
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+. O
+
+
+The O
+results O
+revealed O
+that O
+the O
+nitrogen-filled O
+build B-PARA
+chamber E-PARA
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+the O
+achievement O
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+respect O
+to O
+the O
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+conditions O
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+a O
+consequence O
+of O
+the O
+reduced O
+size O
+of O
+the O
+oxide B-MATE
+inclusions E-MATE
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+
+
+Currently O
+, O
+the O
+laser B-MANP
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+fusion E-MANP
+( O
+L-PBF S-MANP
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+offer O
+a O
+reproducible O
+and O
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+of O
+the O
+processed S-CONPRI
+parts O
+. O
+
+
+Recent O
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+process B-CONPRI
+monitoring E-CONPRI
+focuses O
+strongly O
+on O
+integrated O
+optical B-CHAR
+measurement E-CHAR
+technology O
+. O
+
+
+Besides O
+optical S-CHAR
+sensors O
+, O
+acoustic O
+sensors S-MACEQ
+also O
+seem O
+promising O
+. O
+
+
+Previous O
+studies O
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+of O
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+laser B-MANP
+welding E-MANP
+. O
+
+
+Only O
+a O
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+the O
+potential O
+that O
+lies O
+in O
+the O
+L-PBF S-MANP
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+acoustic O
+signals O
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+statistical O
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+indicating O
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+
+Density B-CHAR
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+Archimedes O
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+measure O
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+
+The O
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+such O
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+Python O
+language O
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+data S-CONPRI
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+
+
+Heat B-MANP
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+Scandium O
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+
+The O
+number O
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+heat S-CONPRI
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+reaches O
+5.2 O
+× O
+1023 O
+m−3 O
+. O
+
+
+Coherently O
+precipitated O
+Al3Sc O
+particles S-CONPRI
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+< O
+5 O
+nm O
+in O
+diameter S-CONPRI
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+
+
+Grain B-CONPRI
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+
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+the O
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+processed O
+condition O
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+to O
+the O
+formation O
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+a O
+desirable O
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+
+
+As S-MATE
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+conventional O
+processing O
+, O
+such O
+alloys S-MATE
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+precipitating O
+a O
+high O
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+finely O
+dispersed O
+coherent O
+Al3 O
+( O
+Scx O
+Zr1-x O
+) O
+intermetallics S-MATE
+, O
+which O
+serve O
+for O
+the O
+improvement O
+of O
+the O
+mechanical B-PRO
+strength E-PRO
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+
+
+Electron B-CHAR
+backscatter I-CHAR
+diffraction E-CHAR
+measurements O
+and O
+transmission B-CHAR
+electron I-CHAR
+microscopy E-CHAR
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+used O
+to O
+determine O
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+the O
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+SLM S-MANP
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+specimens O
+. O
+
+
+In O
+addition O
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+number O
+density S-PRO
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+Al3Sc O
+particles S-CONPRI
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+by O
+atom B-CHAR
+probe I-CHAR
+tomography E-CHAR
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+
+
+The O
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+the O
+as-processed O
+condition O
+can O
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+even O
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+a O
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+treatment E-MANP
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+due O
+to O
+a O
+high O
+density S-PRO
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+intragranular O
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+( O
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+various O
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+particles S-CONPRI
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+grain B-CONPRI
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+. O
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+
+A O
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+certain O
+coarser O
+grained O
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+a O
+local O
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+driving O
+and O
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+defect S-CONPRI
+density O
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+fewer O
+pinning O
+precipitates S-MATE
+. O
+
+
+Applying O
+a O
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+an O
+increase O
+of O
+the O
+density S-PRO
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+≤5 O
+nm O
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+Al3 O
+( O
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+Zr1-x O
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+a O
+factor O
+of O
+4–6 O
+, O
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+3·1023 O
+m−3 O
+to O
+5·1023 O
+m−3 O
+. O
+
+
+Shrinkage S-CONPRI
+stress O
+occur O
+perpendicular O
+to O
+boundaries S-FEAT
+of O
+primary O
+columnar B-PRO
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+
+
+This O
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+forms O
+immobile O
+dislocation S-CONPRI
+networks O
+that O
+hinder O
+dislocation S-CONPRI
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+. O
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+
+Recrystallization S-CONPRI
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+≥1373 O
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+the O
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+
+Networks O
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+connected O
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+block O
+dislocation S-CONPRI
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+. O
+
+
+Dislocation S-CONPRI
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+were O
+found O
+near O
+grain B-CONPRI
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+. O
+
+
+To O
+widen O
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+applications O
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+FeCoCrNi O
+high-entropy O
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+this O
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+
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+2 O
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+
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+
+The O
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+
+The O
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+
+During O
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+dislocations S-CONPRI
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+within O
+it O
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+
+The O
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+formation O
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+twinning S-CONPRI
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+deformation S-CONPRI
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+high-temperature O
+annealing S-MANP
+. O
+
+
+Meanwhile O
+, O
+the O
+ductility S-PRO
+greatly O
+increased O
+, O
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+increasing O
+the O
+potential O
+for O
+industrial S-APPL
+application O
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+HEAs O
+. O
+
+
+First-time O
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+FCC S-CONPRI
++ O
+BCC S-CONPRI
+dual-phase O
+high-entropy O
+alloys S-MATE
+( O
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+) O
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+SLM S-MANP
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+
+New O
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+strategy O
+for O
+attaining O
+strong O
+, O
+yet O
+ductile S-PRO
+DP-HEAs O
+suitable O
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+rapid B-MANP
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+. O
+
+
+Deformation S-CONPRI
+nano-twins O
+, O
+stacking O
+faults O
+and O
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+B2-to-FCC O
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+discovered O
+in O
+BCC S-CONPRI
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+. O
+
+
+The O
+deformation S-CONPRI
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+the O
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+B2 O
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+
+Preparing O
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+alloys S-MATE
+( O
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+has O
+never O
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+by O
+rapid B-MANP
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+. O
+
+
+Here O
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+cubic O
+( O
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+( O
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+based O
+on O
+BCC S-CONPRI
+AlCrCuFeNi O
+HEA O
+using O
+SLM S-MANP
+. O
+
+
+Results O
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+Ni S-MATE
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+AlCrCuFeNix O
+( O
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+. O
+
+
+Especially O
+, O
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+HEA O
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+
+Post-deformation O
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+{ O
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+
+Strain-activated O
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+
+The O
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+
+3D B-MANP
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+conductive O
+nanocomposites O
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+investigated O
+. O
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+
+Conductivity S-PRO
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+. O
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+
+Anisotropy S-PRO
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+order O
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+
+Soft O
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+
+Soft O
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+
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+
+In O
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+
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+
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+
+Overall O
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+
+A O
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+
+The O
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+
+This O
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+
+In O
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+( O
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+
+Jet O
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+The O
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+
+The O
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+
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+
+In O
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+
+The O
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+
+Consequently O
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+
+
+The O
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+
+With O
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+at O
+the O
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+angle O
+grain B-CONPRI
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+( O
+HAGBs O
+) O
+coarsen O
+. O
+
+
+Simultaneously O
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+, O
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+solute O
+content O
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+
+The O
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+alloy E-MATE
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+
+
+Correlations O
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+SLMed S-MANP
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+
+Platelet-shape O
+δ O
+phases O
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+discovered O
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+solution B-MANP
+annealing I-MANP
+treatment E-MANP
+. O
+
+
+Corrosion S-CONPRI
+micro-batteries O
+cause O
+the O
+formation O
+of O
+pits O
+or O
+cracks O
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+secondary O
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+
+Corrosion S-CONPRI
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+
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+
+Evaporation S-CONPRI
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+
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+
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+
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+
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+
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+
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+
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+
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+the O
+volumetric O
+energy B-PARA
+density E-PARA
+. O
+
+
+Thus O
+, O
+this O
+study O
+provides O
+a O
+new O
+insight O
+on O
+the O
+selection O
+of O
+the O
+laser S-ENAT
+condition O
+for O
+SLM-fabricated O
+materials S-CONPRI
+. O
+
+
+This O
+work O
+presents O
+a O
+comprehensive O
+study O
+on O
+the O
+influence O
+of O
+three O
+different O
+processing O
+technologies S-CONPRI
+( O
+Selective B-MANP
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+Melting E-MANP
+, O
+Hot B-MANP
+Pressing E-MANP
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+conventional O
+casting S-MANP
+) O
+on O
+the O
+microstructure S-CONPRI
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+mechanical S-APPL
+and O
+wear S-CONPRI
+behavior O
+of O
+an O
+austenitic S-MATE
+316L B-MATE
+Stainless I-MATE
+Steel E-MATE
+. O
+
+
+A O
+correlation O
+between O
+the O
+processing O
+technologies S-CONPRI
+, O
+the O
+obtained O
+microstructure S-CONPRI
+and O
+the O
+mechanical S-APPL
+and O
+wear S-CONPRI
+behavior O
+was O
+achieved O
+. O
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+
+The O
+results O
+showed O
+that O
+the O
+highest O
+mechanical B-CONPRI
+properties E-CONPRI
+and O
+tribological B-CONPRI
+performance E-CONPRI
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+obtained O
+for O
+316L O
+SS S-MATE
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+when O
+compared O
+to O
+Hot B-MANP
+Pressing E-MANP
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+conventional O
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+
+
+The O
+high O
+wear S-CONPRI
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+by O
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+the O
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+by O
+the O
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+
+In O
+this O
+sense O
+, O
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+Melting E-MANP
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+a O
+promising O
+method O
+to O
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+316L O
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+improved O
+mechanical S-APPL
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+wear B-CONPRI
+performance E-CONPRI
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+
+This O
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+structures O
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+
+The O
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+way O
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+the O
+lattice S-CONPRI
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+
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+
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+evaluated O
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+all O
+the O
+combinations O
+of O
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+
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+large O
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+usual O
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+a O
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+
+It O
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+relative B-PRO
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+any O
+lattice B-FEAT
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+
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+
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+the O
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+yet O
+powerful O
+formalism O
+developed O
+in O
+this O
+work O
+. O
+
+
+A O
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+, O
+mini O
+extruder S-MACEQ
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+pellets S-CONPRI
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+granules S-CONPRI
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+. O
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+
+The O
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+increase O
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+helix O
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+container O
+of O
+n-lobes O
+as S-MATE
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+helical O
+rotor O
+is O
+turned O
+. O
+
+
+A O
+novel O
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+multi-layer O
+Moineau-based O
+pump O
+−easier O
+to O
+build S-PARA
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+implement O
+and O
+clean– O
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+also O
+introduced O
+to O
+extrude S-MANP
+a O
+quantity O
+of O
+viscous O
+material S-MATE
+in O
+vertical S-CONPRI
+direction O
+. O
+
+
+In O
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+( O
+PBF-LB O
+) O
+, O
+material S-MATE
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+continuously O
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+the O
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+pool E-MATE
+, O
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+called O
+spatter S-CHAR
+, O
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+is O
+distributed O
+throughout O
+the O
+build B-PARA
+chamber E-PARA
+. O
+
+
+There O
+is O
+a O
+lack O
+of O
+understanding O
+of O
+the O
+nature O
+of O
+this O
+spatter S-CHAR
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+effect O
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+on O
+the O
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+the O
+final O
+part O
+and O
+the O
+quality S-CONPRI
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+any O
+recycled S-CONPRI
+powder S-MATE
+. O
+
+
+This O
+work O
+reports O
+a O
+detailed O
+investigation O
+of O
+spatter S-CHAR
+metallurgy S-CONPRI
+for O
+Inconel B-MATE
+718 E-MATE
+. O
+
+
+It O
+is O
+seen O
+that O
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+to O
+the O
+virgin O
+material S-MATE
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+6 O
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+
+Oxidation S-MANP
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+in O
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+spots O
+or O
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+of O
+Al2O3 S-MATE
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+TiO2 S-MATE
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+observed O
+on O
+the O
+surface S-CONPRI
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+some O
+of O
+the O
+spatter S-CHAR
+particles S-CONPRI
+. O
+
+
+It O
+is O
+established O
+that O
+this O
+oxide S-MATE
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+the O
+melt B-MATE
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+the O
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+the O
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+, O
+and O
+also O
+that O
+this O
+issue O
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+generic O
+to O
+PBF-LB O
+process S-CONPRI
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+certain O
+alloys S-MATE
+. O
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+
+The O
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+different O
+types O
+of O
+spatter S-CHAR
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+identified O
+and O
+are O
+linked O
+to O
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+mechanisms O
+. O
+
+
+The O
+vaporisation O
+of O
+material S-MATE
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+produces O
+clusters O
+of O
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+composition S-CONPRI
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+Cr S-MATE
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+the O
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+
+The O
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+study O
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+that O
+oxidation S-MANP
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+issues O
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+is O
+needed O
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+the O
+generation O
+and O
+effect O
+of O
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+part O
+and O
+powder S-MATE
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+. O
+
+
+The O
+paper O
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+. O
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+
+SLM S-MANP
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+the O
+high O
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+the O
+as S-MATE
+– O
+built O
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+the O
+surface S-CONPRI
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+subsurface O
+region O
+. O
+
+
+These O
+stresses O
+have O
+a O
+detrimental O
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+the O
+mechanical B-CONPRI
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+especially O
+on O
+the O
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+
+
+Laser S-ENAT
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+the O
+hole O
+– O
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+were O
+performed O
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+
+
+Two O
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+used O
+: O
+a O
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+15-5 O
+precipitation S-CONPRI
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+PH1 O
+and O
+an O
+austenitic S-MATE
+316L O
+. O
+
+
+Different O
+LSP O
+parameters S-CONPRI
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+, O
+varying O
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+energy E-CONPRI
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+
+
+For O
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+
+The O
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+analyzed O
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+a O
+clear O
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+the O
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+
+
+The O
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+“ O
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+the O
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+
+
+Template-free O
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+to O
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+materials B-CHAR
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+
+
+The O
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+new O
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+, O
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+
+A O
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+20 O
+h O
+without O
+human O
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+
+This O
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+3D B-MANP
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+1 O
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+) O
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+1000 O
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+repeatable O
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+rapid B-ENAT
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+of O
+multifunctional O
+devices O
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+
+
+The O
+precise B-CONPRI
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+low O
+minimum O
+feature B-FEAT
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+voltage O
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+long O
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+enables O
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+exploration O
+of O
+a O
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+printed B-CONPRI
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+conventional O
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+
+
+Three-dimensional S-CONPRI
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+3D S-CONPRI
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+can O
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+promising O
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+tissue B-CONPRI
+engineering E-CONPRI
+applications O
+for O
+generating O
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+3D S-CONPRI
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+
+
+The O
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+, O
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+, O
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+FEM S-CONPRI
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+designated O
+mechanical B-CONPRI
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+
+In O
+this O
+study O
+, O
+we O
+generated O
+four O
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+, O
+wavy O
+, O
+hexagonal S-FEAT
+, O
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+shifted O
+microstructures S-MATE
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+and O
+analyzed O
+them O
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+predict O
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+mechanical S-APPL
+behaviors O
+. O
+
+
+For O
+the O
+validity O
+of O
+computational O
+simulations S-ENAT
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+FEM S-CONPRI
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+we O
+measured O
+the O
+mechanical B-CONPRI
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+the O
+3D B-MANP
+printed E-MANP
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+
+
+Results O
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+that O
+the O
+theoretical S-CONPRI
+compressive O
+elastic B-PRO
+moduli E-PRO
+of O
+the O
+designed S-FEAT
+constructs O
+were O
+23.3 O
+, O
+56.5 O
+, O
+67.5 O
+, O
+and O
+1.8 O
+MPa S-CONPRI
+, O
+and O
+the O
+experimental S-CONPRI
+compressive O
+elastic B-PRO
+moduli E-PRO
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+23.6 O
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+0.6 O
+, O
+45.1 O
+± O
+1.4 O
+, O
+56.7 O
+± O
+1.7 O
+, O
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+1.6 O
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+0.2 O
+MPa S-CONPRI
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+lattice S-CONPRI
+, O
+wavy O
+, O
+hexagonal S-FEAT
+, O
+and O
+shifted O
+microstructures S-MATE
+, O
+respectively O
+, O
+while O
+maintaining O
+the O
+same O
+construct O
+dimension S-FEAT
+and O
+porosity S-PRO
+. O
+
+
+In O
+addition O
+, O
+van O
+der O
+Waals O
+hyperelastic O
+material S-MATE
+model O
+was O
+successfully O
+utilized O
+to O
+predict O
+the O
+nonlinear O
+mechanical S-APPL
+behavior O
+of O
+the O
+printed O
+scaffolds S-FEAT
+with O
+different O
+inner O
+geometries S-CONPRI
+. O
+
+
+These O
+findings O
+indicated O
+that O
+the O
+CAD-based O
+FEM S-CONPRI
+prediction O
+could O
+be S-MATE
+used O
+for O
+designing O
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+
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+
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+
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+
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+
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+Likewise O
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+In O
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+
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+using O
+photopolymer S-MATE
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+combination O
+with O
+two O
+additional O
+rotational O
+axes O
+, O
+the O
+printer S-MACEQ
+developed O
+in O
+this O
+work O
+not O
+only O
+allows O
+the O
+traditional O
+layer S-PARA
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+layer S-PARA
+printing O
+, O
+but O
+is O
+also O
+capable O
+of O
+free O
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+printing O
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+
+
+Fumed O
+silica S-MATE
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+used O
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+a O
+filler O
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+order O
+to O
+control O
+the O
+material S-MATE
+viscosity O
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+proper O
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+
+Mechanical B-CHAR
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+were O
+conducted O
+on O
+objects O
+printed O
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+different O
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+filler O
+in O
+the O
+photopolymer S-MATE
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+understand O
+its O
+effect O
+and O
+determine O
+the O
+range S-PARA
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+suitable O
+filler O
+concentration O
+. O
+
+
+Multilayer O
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+, O
+stress S-PRO
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+
+
+Massive O
+martensitic O
+transformation O
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+cladding S-MANP
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+HSS S-MATE
+alloys S-MATE
+, O
+resulted O
+in O
+the O
+compressive O
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+cracking S-CONPRI
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+
+Re-heating O
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+thick O
+multilayer O
+coatings S-APPL
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+an O
+Fe-Cr-Mo-W-V O
+alloy S-MATE
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+detrimental O
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+intermediate O
+layers O
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+
+
+Addition O
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+Co S-MATE
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+LC1 O
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+Fe S-MATE
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+the O
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+coating S-APPL
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+matrix O
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+
+
+Tensile B-CHAR
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+results O
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+a O
+strong O
+adherence O
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+thick O
+multilayer O
+coatings S-APPL
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+the O
+substrate S-MATE
+. O
+
+
+Two O
+high B-MATE
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+steel E-MATE
+( O
+HSS S-MATE
+) O
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+42CrMo4 O
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+kW O
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+YAG E-MATE
+laser B-MACEQ
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+. O
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+
+After O
+optimization S-CONPRI
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+the O
+laser S-ENAT
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+processing O
+parameters S-CONPRI
+for O
+single O
+layers O
+, O
+multilayered O
+clads O
+were O
+produced O
+. O
+
+
+Microstructural B-CHAR
+characterization E-CHAR
+of O
+the O
+laser S-ENAT
+deposits O
+constitutes O
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+of O
+the O
+carbides S-MATE
+and O
+matrix O
+, O
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+was O
+done O
+by O
+using O
+Scanning B-CHAR
+Electron I-CHAR
+Microscopy E-CHAR
+( O
+SEM S-CHAR
+) O
+, O
+Energy B-CHAR
+Dispersive I-CHAR
+Spectroscopy E-CHAR
+( O
+EDS S-CHAR
+) O
+, O
+Electron O
+Backscattered O
+Diffraction S-CHAR
+( O
+EBSD S-CHAR
+) O
+and O
+High B-CHAR
+Resolution I-CHAR
+Transmission I-CHAR
+Electron I-CHAR
+Microscopy E-CHAR
+( O
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+strengthening B-CONPRI
+mechanism E-CONPRI
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+LC1 O
+( O
+Fe-Cr-Mo-W-V O
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+was O
+comprised O
+of O
+a O
+martensitic O
+matrix O
+and O
+retained B-MATE
+austenite E-MATE
+along O
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+networks O
+of O
+VC S-MATE
+and O
+Mo2C O
+eutectic S-CONPRI
+carbides S-MATE
+. O
+
+
+Cr S-MATE
+enriched O
+fine O
+carbides S-MATE
+( O
+Cr7C3 O
+and O
+Cr23C6 O
+) O
+were O
+embedded O
+within O
+the O
+matrix O
+. O
+
+
+During O
+laser B-MANP
+cladding E-MANP
+of O
+the O
+multilayer O
+deposits O
+, O
+cladding S-MANP
+of O
+subsequent O
+layers O
+had O
+a O
+detrimental O
+effect O
+on O
+the O
+hardness S-PRO
+of O
+previously O
+cladded O
+layers O
+, O
+which O
+was O
+due O
+to O
+tempering S-MANP
+of O
+existing O
+lath O
+martensite S-MATE
+. O
+
+
+To O
+overcome O
+the O
+hardness S-PRO
+drop O
+, O
+a O
+new O
+alloy S-MATE
+LC2 O
+( O
+Febal−x-Cr-Mo-W-V-Cox O
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+blended O
+by O
+addition O
+of O
+3–5 O
+% O
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+Co S-MATE
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+LC1 O
+. O
+
+
+The O
+addition O
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+Co S-MATE
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+an O
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+increase O
+in O
+hardness S-PRO
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+sequential O
+layer S-PARA
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+to O
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+of O
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+solid B-MATE
+solution E-MATE
+with O
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+was O
+performed O
+to O
+characterize O
+the O
+nanometer-sized O
+precipitates S-MATE
+evolved O
+during O
+the O
+re-heating O
+. O
+
+
+These O
+carbides S-MATE
+were O
+either O
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+with O
+V S-MATE
+and O
+W O
+or O
+formed O
+from O
+a O
+complex O
+combination O
+of O
+V S-MATE
+, O
+Mo S-MATE
+, O
+W O
+and O
+Cr S-MATE
+with O
+lattice S-CONPRI
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+of O
+0.15 O
+nm O
+to O
+0.26 O
+nm O
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+
+
+An O
+urgent O
+need O
+in O
+the O
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+( O
+LPBF S-MANP
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+around O
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+moving O
+melt B-MATE
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+the O
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+by O
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+fabricated O
+part O
+quality S-CONPRI
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+
+
+The O
+objective O
+of O
+this O
+study O
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+to O
+propose O
+new O
+designs S-FEAT
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+system O
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+the O
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+enhance O
+the O
+removability O
+of O
+spatter S-CHAR
+. O
+
+
+Specifically O
+, O
+a O
+Computational B-CHAR
+Fluid I-CHAR
+Dynamics E-CHAR
+( O
+CFD S-APPL
+) O
+model S-CONPRI
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+the O
+LPBF S-MANP
+gas S-CONPRI
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+system O
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+been O
+developed O
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+simulate O
+the O
+complicated O
+flow O
+behavior O
+inside O
+the O
+build B-PARA
+chamber E-PARA
+. O
+
+
+The O
+movement O
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+spatter S-CHAR
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+been O
+calculated O
+by O
+the O
+Discrete O
+Phase B-CONPRI
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+( O
+DPM O
+) O
+. O
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+
+The O
+fully O
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+CFD-DPM O
+fluid-particle O
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+method O
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+applied O
+to O
+capture O
+the O
+influence O
+of O
+gas S-CONPRI
+flow O
+on O
+solid O
+particles S-CONPRI
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+. O
+
+
+Additionally O
+, O
+an O
+analytical O
+expression O
+is O
+utilized O
+to O
+obtain O
+the O
+threshold O
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+inert B-CONPRI
+gas E-CONPRI
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+upon O
+the O
+powder B-MACEQ
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+. O
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+
+The O
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+distribution S-CONPRI
+in O
+a O
+generic O
+gas S-CONPRI
+chamber O
+design S-FEAT
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+studied O
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+
+
+It O
+was O
+found O
+that O
+the O
+Coanda O
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+a O
+significant O
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+the O
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+process S-CONPRI
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+
+With O
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+
+Polymer B-MANP
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+printing O
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+FDM S-MANP
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+
+Specifically O
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+sequence O
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+received O
+heavy O
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+for O
+space O
+applications O
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+
+However O
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+the O
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+components S-MACEQ
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+3D B-MANP
+printed E-MANP
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+structures O
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+
+
+The O
+work O
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+here O
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+, O
+graphite S-MATE
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+matrix O
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+
+
+The O
+work O
+also O
+examines O
+the O
+effect O
+of O
+these O
+composites S-MATE
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+print B-CONPRI
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+properties S-CONPRI
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+fracture S-CONPRI
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+analysis O
+, O
+micrograph O
+imaging S-APPL
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+and O
+cube S-CONPRI
+satellite O
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+analysis E-CHAR
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+
+
+The O
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+3D B-MANP
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+material O
+systems O
+in O
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+the O
+production S-MANP
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+thermally O
+stable O
+3D B-MANP
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+, O
+supports S-APPL
+, O
+and O
+devices O
+. O
+
+
+Key O
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+thermal O
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+that O
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+be S-MATE
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+through O
+a O
+combination O
+of O
+print S-MANP
+raster O
+direction O
+and O
+material S-MATE
+design S-FEAT
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+
+
+When O
+the O
+materials S-CONPRI
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+in O
+this O
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+other O
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+to O
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+, O
+opening O
+a O
+new O
+door O
+to O
+producing O
+space-ready O
+3D B-MANP
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+
+Inverse O
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+internal O
+surfaces S-CONPRI
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+application O
+in O
+anatomical O
+organ O
+model S-CONPRI
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+
+
+Inverse O
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+printing O
+strategies O
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+speed O
+up O
+3D B-MANP
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+and O
+increase O
+efficiency O
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+
+
+Prepolymer S-MATE
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+high O
+transparency O
+, O
+and O
+has O
+shear B-CONPRI
+thinning E-CONPRI
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+and O
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+characteristics O
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+
+
+The O
+most O
+current O
+3D B-MANP
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+involves O
+the O
+combination O
+of O
+additional O
+processes S-CONPRI
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+such O
+as S-MATE
+casting O
+and O
+demolding S-CONPRI
+, O
+to O
+produce O
+an O
+organ O
+model S-CONPRI
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+
+
+This O
+method O
+requires O
+professionals O
+to O
+invest O
+a O
+considerable O
+amount O
+of O
+time O
+in O
+editing O
+the O
+model S-CONPRI
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+post-processing S-CONPRI
+activities O
+. O
+
+
+In O
+this O
+work O
+, O
+embedded B-MANP
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+EMB3D S-MANP
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+is O
+performed O
+in O
+a O
+transparent S-CONPRI
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+medium O
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+
+Based O
+on O
+a O
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+new O
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+strategy O
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+, O
+which O
+could O
+be S-MATE
+considered O
+as S-MATE
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+inverse O
+process S-CONPRI
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+
+
+During O
+printing O
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+a O
+closed O
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+formed O
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+a O
+release O
+ink S-MATE
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+a O
+capillary B-MACEQ
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+
+After O
+printing O
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+a O
+solid O
+part O
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+and O
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+object O
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+peeled O
+off O
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+the O
+closed O
+shell S-MACEQ
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+
+The O
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+objects O
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+multi-internal O
+surfaces S-CONPRI
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+
+Moreover O
+, O
+it O
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+be S-MATE
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+providing O
+a O
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+A O
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+
+The O
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+
+Porosity S-PRO
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+the O
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+reported O
+literature O
+data S-CONPRI
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+A O
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+fusion S-CONPRI
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+
+
+The O
+inputs O
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+the O
+simulation S-ENAT
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+spacing E-PARA
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+layer B-PARA
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+melt-pool O
+cross-sectional O
+area S-PARA
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+
+Melt-pool O
+areas S-PARA
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+in O
+the O
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+be S-MATE
+obtained O
+from O
+experiments O
+, O
+or O
+estimated O
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+the O
+analytical O
+Rosenthal B-CONPRI
+equation E-CONPRI
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+
+The O
+necessary O
+material S-MATE
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+, O
+including O
+absorptivity O
+for O
+laser-based O
+melting S-MANP
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+
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+including O
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+, O
+atenolol S-MATE
+, O
+hydrochlorothiazide S-MATE
+and O
+amlodipine S-MATE
+. O
+
+
+Although O
+successful O
+in O
+its O
+fabrication S-MANP
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+the O
+first O
+time O
+, O
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+report O
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+unexpected O
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+a O
+photopolymer S-MATE
+and O
+drug O
+. O
+
+
+Fourier B-ENAT
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+( O
+FTIR S-CHAR
+) O
+spectroscopy S-CONPRI
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+Magnetic I-CONPRI
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+( O
+NMR S-CHAR
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+group O
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+
+The O
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+
+Photopolymerization-based S-CONPRI
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+promising O
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+
+However O
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+deteriorating O
+the O
+final O
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+
+To O
+overcome O
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+FPP S-MANP
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+. O
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+
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+
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+
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+
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+
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+
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+
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+
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+
+Here O
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+
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+
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+
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+printing O
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+printed O
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+
+SMA O
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+
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+
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+
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+
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+
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+
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+
+Furthermore O
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+
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+
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+
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+A O
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+
+Optical S-CHAR
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+
+Nowadays O
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+
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+
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+
+Additionally O
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+
+This O
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+
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+self-replicated O
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+
+The O
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+innovative O
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+
+A O
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+
+Measures O
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+
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+
+The O
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+In O
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+
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+
+In O
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+In O
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+applications O
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+
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+
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+The O
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+
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+
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+
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+
+Sisal O
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+
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+
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+
+We O
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+
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+
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+
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+
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+
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+
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+
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+
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+
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+
+Commercial O
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+) O
+, O
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+exposed O
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+doses O
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+up O
+to O
+5.3 O
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+
+
+The O
+suitability O
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+evaluated O
+by O
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+
+We O
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+all O
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+
+We O
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+these O
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+
+The O
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+
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+strength S-PRO
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+bulk O
+filament S-MATE
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+
+
+Specially O
+designed S-FEAT
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+were O
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+test O
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+bulk O
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+by O
+printing O
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+LHs O
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+five O
+different O
+EFWs O
+. O
+
+
+Both O
+F S-MANP
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+Z O
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+demonstrated O
+bulk O
+material B-PRO
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+. O
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+
+In O
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+, O
+strain-at-fracture O
+, O
+specific O
+load-bearing S-FEAT
+capacity S-CONPRI
+, O
+and O
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+Z O
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+grooves O
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+
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+localised O
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+opposed O
+to O
+assumed O
+incomplete O
+bonding S-CONPRI
+of O
+the O
+polymer S-MATE
+across O
+the O
+interlayer O
+interface S-CONPRI
+) O
+. O
+
+
+Additionally O
+, O
+effects O
+of O
+variation S-CONPRI
+in O
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+and O
+layer S-PARA
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+were O
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+found O
+to O
+have O
+no O
+influence O
+on O
+interlayer O
+bond B-CONPRI
+strength E-CONPRI
+. O
+
+
+The O
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+of O
+the O
+results O
+to O
+other O
+materials S-CONPRI
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+future O
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+. O
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+
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+like O
+the O
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+
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+This O
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+of O
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+geometries S-CONPRI
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+high O
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+
+However O
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+the O
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+, O
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+part O
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+
+A O
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+capable O
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+> O
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+
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+PLA S-MATE
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+
+However O
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+FFF S-MANP
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+
+The O
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+to O
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+
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+
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+electron I-MACEQ
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+
+Filament S-MATE
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+
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+
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+
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+
+Steady O
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+
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+
+The O
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+
+The O
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+
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+
+In O
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+achieve O
+a O
+more O
+compact S-MANP
+high O
+performance S-CONPRI
+PCB O
+structure S-CONPRI
+. O
+
+
+This O
+study O
+presents O
+development O
+of O
+a O
+test O
+method O
+for O
+characterization O
+of O
+interlayer O
+, O
+mode-I O
+fracture S-CONPRI
+toughness O
+of O
+fused B-MANP
+filament I-MANP
+fabrication E-MANP
+( O
+FFF S-MANP
+) O
+materials S-CONPRI
+using O
+a O
+modified O
+double O
+cantilever B-MACEQ
+beam E-MACEQ
+( O
+DCB O
+) O
+test O
+. O
+
+
+This O
+test O
+consists O
+of O
+DCB O
+specimen O
+fabricated S-CONPRI
+from O
+using O
+unidirectional S-CONPRI
+FFF S-MANP
+layers O
+, O
+an O
+8 O
+μm O
+Kapton O
+starter O
+crack O
+inserted O
+in O
+the O
+midplane S-CONPRI
+during O
+the O
+printing B-MANP
+process E-MANP
+, O
+and O
+reinforcing O
+glass/epoxy O
+doublers O
+to O
+prevent O
+DCB O
+arm O
+failure S-CONPRI
+during O
+loading O
+. O
+
+
+DCB O
+specimens O
+are O
+manufactured S-CONPRI
+with O
+a O
+commercially O
+available O
+3D B-MACEQ
+printer E-MACEQ
+using O
+unreinforced O
+Acrylonitrile B-MATE
+Butadiene I-MATE
+Styrene E-MATE
+( O
+ABS S-MATE
+) O
+and O
+chopped O
+carbon-fiber-reinforced O
+ABS S-MATE
+( O
+CF-ABS O
+) O
+filaments S-MATE
+. O
+
+
+To O
+examine O
+the O
+effect O
+of O
+the O
+FFF S-MANP
+printing O
+process S-CONPRI
+on O
+fracture S-CONPRI
+toughness O
+, O
+additional O
+ABS S-MATE
+and O
+CF-ABS O
+specimens O
+are O
+hot-press O
+molded O
+using O
+the O
+filament S-MATE
+material O
+, O
+and O
+tested O
+with O
+the O
+single O
+end O
+notch S-FEAT
+bend O
+( O
+SENB O
+) O
+specimen O
+configuration S-CONPRI
+. O
+
+
+The O
+fracture S-CONPRI
+toughness O
+data S-CONPRI
+from O
+DCB O
+and O
+SENB O
+tests O
+reveal O
+that O
+the O
+FFF S-MANP
+process O
+significantly O
+lowers O
+the O
+mode-I O
+fracture S-CONPRI
+toughness O
+of O
+ABS S-MATE
+and O
+CF-ABS O
+. O
+
+
+For O
+both O
+materials S-CONPRI
+, O
+in B-CONPRI
+situ E-CONPRI
+thermal O
+imaging S-APPL
+and O
+post-mortem O
+fractography S-CHAR
+shows O
+, O
+respectively O
+, O
+rapid O
+cool-down O
+of O
+the O
+rasters O
+during O
+filament S-MATE
+deposition S-CONPRI
+and O
+presence O
+of O
+voids S-CONPRI
+between O
+adjacent O
+raster O
+roads O
+; O
+both O
+of O
+which O
+serve O
+to O
+reduce O
+fracture S-CONPRI
+toughness O
+. O
+
+
+For O
+CF-ABS O
+specimens O
+, O
+fracture S-CONPRI
+toughness O
+is O
+further O
+reduced O
+by O
+inclusion S-MATE
+of O
+poorly O
+wetted O
+chopped O
+carbon B-MATE
+fibers E-MATE
+. O
+
+
+Although O
+this O
+study O
+did O
+not O
+attempt O
+to O
+optimize O
+the O
+fracture S-CONPRI
+performance O
+of O
+FFF S-MANP
+specimens O
+, O
+the O
+results O
+demonstrate O
+that O
+the O
+proposed O
+methodology S-CONPRI
+is O
+suitable O
+for O
+design S-FEAT
+and O
+optimization S-CONPRI
+of O
+FFF S-MANP
+processes O
+for O
+improved O
+interlayer O
+fracture S-CONPRI
+performance O
+. O
+
+
+This O
+paper O
+presents O
+an O
+end-to-end O
+design B-CONPRI
+process E-CONPRI
+for O
+compliance O
+minimization-based O
+topological B-FEAT
+optimization E-FEAT
+of O
+cellular B-FEAT
+structures E-FEAT
+through O
+to O
+the O
+realization O
+of O
+a O
+final O
+printed O
+product O
+. O
+
+
+Homogenization S-MANP
+is O
+used O
+to O
+derive O
+properties S-CONPRI
+representative O
+of O
+these O
+structures O
+through O
+direct O
+numerical B-ENAT
+simulation E-ENAT
+of O
+unit B-CONPRI
+cell E-CONPRI
+models O
+. O
+
+
+The O
+resulting O
+homogenized S-MANP
+properties O
+are O
+then O
+used O
+assuming O
+uniform O
+distribution S-CONPRI
+of O
+the O
+cellular B-FEAT
+structure E-FEAT
+to O
+compute O
+the O
+macroscale S-CONPRI
+structure O
+. O
+
+
+Results O
+are O
+presented O
+that O
+illustrate O
+the O
+fine-scale O
+stresses O
+developed O
+in O
+the O
+macroscale S-CONPRI
+optimized O
+part O
+as S-MATE
+well O
+as S-MATE
+the O
+effect O
+that O
+fine-scale O
+structure S-CONPRI
+has O
+on O
+the O
+optimized O
+topology S-CONPRI
+. O
+
+
+Quite O
+fine O
+cellular B-FEAT
+structures E-FEAT
+are O
+shown O
+to O
+be S-MATE
+possible O
+using O
+this O
+method O
+. O
+
+
+Fused B-MANP
+Filament I-MANP
+Fabrication E-MANP
+( O
+FFF S-MANP
+) O
+is O
+the O
+most O
+widely O
+available O
+Additive B-MANP
+Manufacturing E-MANP
+technology O
+. O
+
+
+Offering O
+the O
+possibility O
+of O
+producing O
+complex B-CONPRI
+geometries E-CONPRI
+in O
+a O
+compressed O
+product B-CONPRI
+development E-CONPRI
+cycle O
+and O
+in O
+a O
+plethora O
+of O
+materials S-CONPRI
+, O
+it O
+comes O
+as S-MATE
+no O
+surprise O
+that O
+FFF S-MANP
+is O
+attractive O
+to O
+multiple O
+industries S-APPL
+, O
+including O
+the O
+automotive S-APPL
+and O
+aerospace S-APPL
+segments O
+. O
+
+
+However O
+, O
+the O
+high O
+anisotropy S-PRO
+of O
+parts O
+developed O
+through O
+this O
+technique O
+implies O
+that O
+failure S-CONPRI
+prediction O
+is O
+extremely O
+difficult O
+-a O
+requirement O
+that O
+must O
+be S-MATE
+satisfied O
+to O
+guarantee O
+the O
+safety S-CONPRI
+of O
+the O
+final O
+user O
+. O
+
+
+This O
+work O
+applies O
+a O
+criterion O
+that O
+incorporates O
+stress S-PRO
+interactions O
+to O
+define O
+a O
+3D S-CONPRI
+failure O
+envelope O
+that O
+could O
+prove O
+an O
+invaluable O
+tool S-MACEQ
+in O
+formalizing O
+the O
+embrace O
+of O
+FFF S-MANP
+in O
+industry S-APPL
+. O
+
+
+Tensile S-PRO
+, O
+compressive O
+and O
+torsion B-CHAR
+tests E-CHAR
+were O
+executed O
+on O
+coupons O
+developed O
+in O
+a O
+traditional O
+FFF S-MANP
+printer O
+, O
+as S-MATE
+well O
+as S-MATE
+a O
+customized O
+, O
+6-axis O
+robotic O
+printer S-MACEQ
+necessary O
+to O
+produce O
+specimens O
+in O
+out O
+of O
+ordinary O
+orientations S-CONPRI
+. O
+
+
+These O
+tests O
+were O
+used O
+to O
+calculate O
+the O
+parameters S-CONPRI
+of O
+the O
+mathematical S-CONPRI
+function O
+that O
+describe O
+the O
+failure S-CONPRI
+envelope O
+. O
+
+
+Mechanical B-CHAR
+tests E-CHAR
+clearly O
+showed O
+significant O
+difference O
+between O
+tensile S-PRO
+, O
+compressive O
+and O
+shear B-PRO
+strengths E-PRO
+. O
+
+
+The O
+calculated O
+envelope O
+shows O
+strong O
+interactions O
+between O
+axial O
+loads O
+, O
+and O
+a O
+considerable O
+interaction O
+between O
+shear B-PRO
+stresses E-PRO
+and O
+loads O
+applied O
+in O
+directions O
+parallel O
+and O
+perpendicular O
+to O
+the O
+beads S-CHAR
+. O
+
+
+A O
+new O
+class O
+of O
+high-performance O
+resins S-MATE
+are O
+available O
+for O
+additive B-MANP
+manufacturing E-MANP
+with O
+the O
+introduction O
+of O
+Digital B-MANP
+Light I-MANP
+Synthesis E-MANP
+( O
+DLS S-MANP
+) O
+technology S-CONPRI
+. O
+
+
+In O
+combination O
+with O
+Continuous B-MANP
+Liquid I-MANP
+Interface I-MANP
+Production E-MANP
+( O
+CLIP S-MANP
+) O
+, O
+DLS S-MANP
+uses O
+ultraviolet B-CONPRI
+light E-CONPRI
+and O
+oxygen S-MATE
+to O
+continuously O
+grow O
+objects O
+from O
+a O
+pool O
+of O
+resin S-MATE
+instead O
+of O
+printing O
+them O
+layer-by-layer S-CONPRI
+, O
+subsequently O
+increasing O
+the O
+printing B-PARA
+speed E-PARA
+and O
+the O
+mechanical S-APPL
+performance O
+. O
+
+
+For O
+many O
+DLS S-MANP
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+systems O
+, O
+a O
+secondary O
+thermal O
+curing S-MANP
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+is O
+required O
+in O
+order O
+to O
+reach O
+the O
+final O
+material B-CONPRI
+properties E-CONPRI
+after O
+printing O
+. O
+
+
+This O
+step S-CONPRI
+is O
+a O
+major O
+limiting O
+factor O
+in O
+the O
+production S-MANP
+time O
+of O
+the O
+DLS S-MANP
+process O
+, O
+as S-MATE
+materials O
+may O
+require O
+several O
+hours O
+of O
+thermal O
+post O
+curing S-MANP
+. O
+
+
+The O
+aim O
+of O
+this O
+study O
+is O
+to O
+optimize O
+this O
+secondary O
+curing S-MANP
+cycle O
+for O
+the O
+epoxy-based O
+resin S-MATE
+EPX O
+82 O
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+reducing O
+the O
+thermal O
+curing B-PARA
+time E-PARA
+while O
+avoiding O
+a O
+negative O
+influence O
+on O
+the O
+final O
+mechanical B-CONPRI
+properties E-CONPRI
+. O
+
+
+Differential O
+scanning S-CONPRI
+calorimetry O
+( O
+DSC S-CHAR
+) O
+was O
+used O
+with O
+different O
+heating S-MANP
+rates O
+and O
+a O
+chemical B-CONPRI
+reaction E-CONPRI
+model O
+was O
+developed O
+. O
+
+
+The O
+Di O
+Benedetto O
+relationship O
+was O
+used O
+to O
+include O
+diffusion S-CONPRI
+control O
+for O
+high O
+degrees O
+of O
+cure S-CONPRI
+. O
+
+
+Powder B-MANP
+Bed I-MANP
+Fusion E-MANP
+( O
+PBF S-MANP
+) O
+is O
+a O
+range S-PARA
+of O
+advanced O
+manufacturing B-MANP
+technologies E-MANP
+that O
+can O
+fabricate S-MANP
+three-dimensional O
+assets O
+directly O
+from O
+CAD S-ENAT
+data O
+, O
+on O
+a O
+successive O
+layer-by-layer S-CONPRI
+strategy O
+by O
+using O
+thermal B-CONPRI
+energy E-CONPRI
+, O
+typically O
+from O
+a O
+laser B-MACEQ
+source E-MACEQ
+, O
+to O
+irradiate O
+and O
+fuse S-MANP
+particles O
+within O
+a O
+powder S-MATE
+bed.The O
+aim O
+of O
+this O
+paper O
+was O
+to O
+investigate O
+the O
+application O
+of O
+this O
+advanced O
+manufacturing S-MANP
+technique O
+to O
+process S-CONPRI
+ceramic S-MATE
+multicomponent O
+materials S-CONPRI
+into O
+3D S-CONPRI
+layered O
+structures O
+. O
+
+
+The O
+materials S-CONPRI
+used O
+matched O
+those O
+found O
+on O
+the O
+Lunar O
+and O
+Martian O
+surfaces S-CONPRI
+. O
+
+
+The O
+indigenous O
+extra-terrestrial O
+Lunar O
+and O
+Martian O
+materials S-CONPRI
+could O
+potentially O
+be S-MATE
+used O
+for O
+manufacturing S-MANP
+physical O
+assets O
+onsite O
+( O
+i.e. O
+, O
+off-world O
+) O
+on O
+future O
+planetary O
+exploration O
+missions O
+and O
+could O
+cover O
+a O
+range S-PARA
+of O
+potential O
+applications O
+including O
+: O
+infrastructure O
+, O
+radiation S-MANP
+shielding O
+, O
+thermal O
+storage O
+, O
+etc.Two O
+different O
+simulants O
+of O
+the O
+mineralogical O
+and O
+basic O
+properties S-CONPRI
+of O
+Lunar O
+and O
+Martian O
+indigenous O
+materials S-CONPRI
+were O
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+for O
+the O
+purpose O
+of O
+this O
+study O
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+processed S-CONPRI
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+commercially O
+available O
+laser B-MANP
+additive I-MANP
+manufacturing E-MANP
+equipment S-MACEQ
+. O
+
+
+The O
+results O
+of O
+the O
+laser B-CONPRI
+processing E-CONPRI
+were O
+investigated O
+and O
+quantified O
+through O
+mechanical S-APPL
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+, O
+optical S-CHAR
+and O
+scanning B-CHAR
+electron I-CHAR
+microscopy E-CHAR
+, O
+X-ray S-CHAR
+fluorescence S-CHAR
+spectroscopy O
+, O
+thermo-gravimetric O
+analysis O
+, O
+spectrometry O
+, O
+and O
+finally O
+X-ray S-CHAR
+diffraction.The O
+research S-CONPRI
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+in O
+the O
+identification O
+of O
+a O
+range S-PARA
+of O
+process B-CONPRI
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+the O
+successful O
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+Lunar O
+and O
+Martian O
+ceramic S-MATE
+multicomponent O
+simulant O
+materials S-CONPRI
+. O
+
+
+The O
+feasibility S-CONPRI
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+using O
+thermal O
+based O
+additive B-MANP
+manufacturing E-MANP
+with O
+multi-component O
+ceramic B-MATE
+materials E-MATE
+has O
+therefore O
+been O
+established O
+, O
+which O
+represents O
+a O
+potential O
+solution S-CONPRI
+to O
+off-world O
+bulk O
+structure B-CONPRI
+manufacture E-CONPRI
+for O
+future O
+human O
+space O
+exploration O
+. O
+
+
+This O
+study O
+investigates S-CONPRI
+the O
+moisture O
+absorption S-CONPRI
+characteristics O
+of O
+the O
+ULTEM® O
+9085 O
+filament S-MATE
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+how O
+the O
+uptake O
+concentration O
+affects O
+the O
+quality S-CONPRI
+of O
+material B-MANP
+extrusion E-MANP
+manufactured B-CONPRI
+3-D E-CONPRI
+parts O
+. O
+
+
+The O
+rate O
+of O
+transport S-CHAR
+was O
+modeled O
+by O
+Fickian O
+diffusion S-CONPRI
+and O
+diffusion S-CONPRI
+coefficients O
+were O
+obtained O
+for O
+various O
+exposure S-CONPRI
+conditions O
+. O
+
+
+Moduli O
+, O
+strain S-PRO
+to O
+failure S-CONPRI
+and O
+ultimate B-PRO
+strength E-PRO
+were O
+evaluated O
+in O
+the O
+XY O
+( O
+flat O
+horizontal O
+) O
+and O
+ZX O
+( O
+vertical S-CONPRI
+) O
+direction O
+relative O
+to O
+the O
+build B-MACEQ
+plate E-MACEQ
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+. O
+
+
+Image B-CONPRI
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+corresponding O
+fracture S-CONPRI
+surfaces O
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+evaluated O
+for O
+consolidation S-CONPRI
+, O
+porosity S-PRO
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+behavior O
+. O
+
+
+Mechanical B-CHAR
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+data S-CONPRI
+showed O
+a O
+significant O
+decrease O
+in O
+tensile B-PRO
+strength E-PRO
+( O
+> O
+60 O
+% O
+) O
+and O
+failure S-CONPRI
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+( O
+> O
+50 O
+% O
+) O
+over O
+the O
+range S-PARA
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+filament S-MATE
+moisture O
+levels O
+investigated O
+. O
+
+
+A O
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+in O
+failure S-CONPRI
+strain O
+of O
+41 O
+% O
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+observed O
+with O
+moisture O
+levels O
+as S-MATE
+low O
+as S-MATE
+0.16 O
+% O
+. O
+
+
+This O
+degradation S-CONPRI
+was O
+especially O
+sensitive O
+in O
+parts O
+printed O
+in O
+the O
+vertical S-CONPRI
+direction O
+, O
+which O
+resulted O
+in O
+an O
+ultimate O
+failure S-CONPRI
+strain O
+of O
+only O
+1 O
+% O
+. O
+
+
+The O
+changes O
+in O
+mechanical S-APPL
+performance O
+are O
+believed O
+to O
+be S-MATE
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+to O
+a O
+combination O
+of O
+entrapped O
+volatiles O
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+in O
+increased O
+porosity S-PRO
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+higher O
+moisture O
+levels O
+as S-MATE
+well O
+as S-MATE
+moisture O
+induced O
+pseudo-crosslinking O
+at O
+lower O
+concentrations O
+. O
+
+
+Optical S-CHAR
+micrographs O
+showed O
+that O
+specimens O
+with O
+0.16 O
+% O
+moisture O
+or O
+greater O
+were O
+filled O
+with O
+observable O
+porosity S-PRO
+and O
+increased O
+surface B-PRO
+roughness E-PRO
+. O
+
+
+The O
+rheological S-PRO
+behavior O
+of O
+extruded S-MANP
+material O
+indicated O
+plasticization O
+as S-MATE
+evidenced O
+by O
+melt B-PARA
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+measurements O
+and O
+changes O
+in O
+the O
+flow O
+characteristics O
+of O
+moisture-exposed O
+extrudate S-MATE
+. O
+
+
+DMA B-CONPRI
+data E-CONPRI
+show O
+a O
+distinct O
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+
+Printed O
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+
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+
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+
+The O
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+
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+
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+Several O
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+composites O
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+comparable O
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+ECM S-MANP
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+
+This O
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+attributed O
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+highly O
+aligned O
+fibers S-MATE
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+IM O
+and O
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+. O
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+
+However O
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+
+The O
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+maximum O
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+minimum O
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+0.007 O
+% O
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+the O
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+least O
+fiber S-MATE
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+4.3 O
+% O
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+
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+
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+
+Convergent O
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+
+For O
+rotational O
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+randomized O
+fiber S-MATE
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+
+Methods O
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+counteract O
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+
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+
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+
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+
+In O
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+
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+
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+
+To O
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+
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+
+In O
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+
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+
+To O
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+
+Detailed O
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+
+In O
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+
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+The O
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+
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+
+The O
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+This O
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+
+They O
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+To O
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+In O
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+In O
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+In O
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+
+The O
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+This O
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+
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+
+The O
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+
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+
+Low O
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+
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+
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+
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+
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+
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