cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14321629.v1
title: Effect of titanium content on the porosity and hardness of Cu-Ti-TiC composite sintered by abnormal glow discharge

description: ABSTRACT Copper metal matrix composites reinforced with TiC 1 % (%w/w) and titanium mass with fractions of 10 %, 15 % and 20 % were synthesized and characterized in order to evaluate the porosity in the material generated by the presence of titanium and material hardness. The MMC’s were manufactured by powder metallurgical route that included: mechanical and ultrasonic mixing of Cu-Ti-TiC in liquid suspension of 2-propanol, following by drying with subsequent uniaxial cold compaction at 400 MPa. Sintering by abnormal glow discharge at 850 °C in 10 % nitrogen and 90 % argon atmosphere; sintering time of 30 minutes and later cooling. Sintered samples were characterized by X-ray diffraction to determine the material phases. The morphological and compositional characterization were performed by scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS). Porosity in green and sintered conditions were estimated by digital image analysis. As a result, in the green samples were evidenced a porosity in the range between 5,2% and 7,21% with the three fractions of Ti. The sintered samples value close to 13,6% were obtained with concentrations of 20% of Ti. The X-ray diffraction analysis showed the majority presence of the Cu3Ti and CuTi2 phases at 850 °C. The results by SEM and EDS exhibited the distribution of titanium associated with diffusive phenomena during sintering process. The hardness data were determined with the use of Vickers microdurometer with a load of 100 gf, showing that the presence of higher titanium content had influenced the hardness due to the formation of intermetallic phases, increasing its values up to 454 HV.
DOI: 10.6084/m9.figshare.14321631.v1
title: Study on the surface integrity of AISI 4140 steel after turning

description: ABSTRACT Machine components are usually subjected to cyclic loads, which may lead to failure, even when the component is subjected to elastic deformations only. Manufacturing processes are capable of affecting roughness and inducing residual stresses of distinct levels and depths, being able to affect the component performance and lifespan. This work investigates the influence of turning parameters (cutting speed, feed and depth of cut) on surface roughness, residual stress and fatigue life of hardened AISI 4140 steel (40 HRC). Feed is the most influential parameter affecting surface roughness. It was noticed that the cutting parameters did affect the residual stress profile, i.e., tensile residual stresses of higher intensity were induced when higher cutting speeds were employed and reaching deeper layers when higher feed and lower depth of cut values were used. The fatigue life was evaluated under rotating bending tests, which indicated a combined influence of feed and depth of cut. At lower feeds, the increase of depth of cut resulted in longer lives, however, an opposite behavior was noted at higher feeds. Longer fatigue lives were observed after turning at higher cutting speeds and depths of cut combined with lower feeds.
DOI: 10.6084/m9.figshare.14321631
title: Study on the surface integrity of AISI 4140 steel after turning

description: ABSTRACT Machine components are usually subjected to cyclic loads, which may lead to failure, even when the component is subjected to elastic deformations only. Manufacturing processes are capable of affecting roughness and inducing residual stresses of distinct levels and depths, being able to affect the component performance and lifespan. This work investigates the influence of turning parameters (cutting speed, feed and depth of cut) on surface roughness, residual stress and fatigue life of hardened AISI 4140 steel (40 HRC). Feed is the most influential parameter affecting surface roughness. It was noticed that the cutting parameters did affect the residual stress profile, i.e., tensile residual stresses of higher intensity were induced when higher cutting speeds were employed and reaching deeper layers when higher feed and lower depth of cut values were used. The fatigue life was evaluated under rotating bending tests, which indicated a combined influence of feed and depth of cut. At lower feeds, the increase of depth of cut resulted in longer lives, however, an opposite behavior was noted at higher feeds. Longer fatigue lives were observed after turning at higher cutting speeds and depths of cut combined with lower feeds.
DOI: 10.6084/m9.figshare.14321632
title: Metallurgical comparison of Al2Si2.5Cu and Al4Si2.5Cu semisolid alloys produced by equal channel angular pressing process

description: ABSTRACT The present work aims to contribute to the development of semisolid technology by analyzing the Al2Si2.5Cu and Al4Si2.5Cu alloys produced by severe plastic deformation - ECAP method (equal channel angular pressing) in order to understand the microstructural behavior of these materials. The alloys submitted to reheating treatment in condition of 60% solid fraction at treatment times of 210 s. Microstructural characterization by optical microscopy through analysis of primary globule size, grain size, circularity shape factor and rheocast quality index (RQI). The semisolid alloys produced by ECAP were compared with the traditional processing techniques, namely electromagnetic stirring and grain ultra-refining technique, the Al2Si2.5Cu alloy there was no reduction in size of primary globules and grains, but the Al4Si2.5Cu alloy there was a total reduction of 53 μm for the primary globules size and approximately 50 μm for the grains size, favors characteristic the thixoforming process.
DOI: 10.6084/m9.figshare.14321632.v1
title: Metallurgical comparison of Al2Si2.5Cu and Al4Si2.5Cu semisolid alloys produced by equal channel angular pressing process

description: ABSTRACT The present work aims to contribute to the development of semisolid technology by analyzing the Al2Si2.5Cu and Al4Si2.5Cu alloys produced by severe plastic deformation - ECAP method (equal channel angular pressing) in order to understand the microstructural behavior of these materials. The alloys submitted to reheating treatment in condition of 60% solid fraction at treatment times of 210 s. Microstructural characterization by optical microscopy through analysis of primary globule size, grain size, circularity shape factor and rheocast quality index (RQI). The semisolid alloys produced by ECAP were compared with the traditional processing techniques, namely electromagnetic stirring and grain ultra-refining technique, the Al2Si2.5Cu alloy there was no reduction in size of primary globules and grains, but the Al4Si2.5Cu alloy there was a total reduction of 53 μm for the primary globules size and approximately 50 μm for the grains size, favors characteristic the thixoforming process.
DOI: 10.6084/m9.figshare.14321634.v1
title: Behavior of concrete subjected to high temperatures

description: ABSTRACT The fire response of structural elements depends on the thermal, mechanical and deformation properties of concrete. The properties vary significantly with temperature and depend on the composition and characteristics of the concrete. Thus, the objective of this work was to perform an analysis of the behavior of concrete subjected to high temperatures. For this, the experimental programs adopted were to investigate the behavior of the modulus of elasticity of the concrete, the resistance to the residual compression according to the type of cooling, exposure time, the concrete fck and the addition content of polypropylene fiber, besides of the analysis of mass loss and ultrasonic pulse velocity. The temperatures at which the concrete was subjected were 200 °C, 400 °C, 600 °C and 800 °C. It can be concluded that concrete exposed to high temperatures undergoes significant deterioration such as reduction of modulus of elasticity and compressive strength, spalling of concrete and consequently loss of durability. The addition of polypropylene fibers helped prevent spalling at temperatures up to 600 ºC. Furthermore, based on statistical tests, the results showed that the A type of cooling does not influence the residual resistance, since the exposure time, the type of fck and the addition content of polypropylene fibers influence significantly.
DOI: 10.6084/m9.figshare.14321634
title: Behavior of concrete subjected to high temperatures

description: ABSTRACT The fire response of structural elements depends on the thermal, mechanical and deformation properties of concrete. The properties vary significantly with temperature and depend on the composition and characteristics of the concrete. Thus, the objective of this work was to perform an analysis of the behavior of concrete subjected to high temperatures. For this, the experimental programs adopted were to investigate the behavior of the modulus of elasticity of the concrete, the resistance to the residual compression according to the type of cooling, exposure time, the concrete fck and the addition content of polypropylene fiber, besides of the analysis of mass loss and ultrasonic pulse velocity. The temperatures at which the concrete was subjected were 200 °C, 400 °C, 600 °C and 800 °C. It can be concluded that concrete exposed to high temperatures undergoes significant deterioration such as reduction of modulus of elasticity and compressive strength, spalling of concrete and consequently loss of durability. The addition of polypropylene fibers helped prevent spalling at temperatures up to 600 ºC. Furthermore, based on statistical tests, the results showed that the A type of cooling does not influence the residual resistance, since the exposure time, the type of fck and the addition content of polypropylene fibers influence significantly.
DOI: 10.6084/m9.figshare.14321635
title: Influence of the Solidification Defects on the Corrosion Resistance of Zamac 5 Obtained by Squeeze Casting

description: ABSTRACT Sanitary metals are objects that, according to the current requirements of the consumer market, must be both corrosion resistant and beautiful, with a shiny mirror appearance. These are usually produced in cast brass because of their easy processing and electrodeposition characteristics. However, to reduce production costs, brass has been replaced by zinc alloys in the manufacture of these components. Zamac has properties such as low melting point compared to brass, which allows the production of thin-walled parts and complex geometries. Pressure injection to obtain zinc hypoeutec alloys (Zamac 5) allows higher productivity associated with better dimensional characteristics, costing about 30% less than brass. This study presents the macro and microstructural characterization of Zamac 5 injected under pressure, relating them to the corrosion resistance of the alloy. For this, saline fog tests and analyzes were performed by scanning electron microscopy, microhardness tests and electrochemical corrosion tests. The Zamac 5 injected under pressure presented non-uniform corrosion in distinct regions of the part when subjected to the aggressive atmosphere. The results also showed that this fact is associated with porosity defects from the alloy manufacturing process. The microhardness of the alloy was also associated with defects from the manufacturing process. Finally, it was evidenced that the electrochemical behavior of the alloy is little influenced by the presence of the defects.
DOI: 10.6084/m9.figshare.14321635.v1
title: Influence of the Solidification Defects on the Corrosion Resistance of Zamac 5 Obtained by Squeeze Casting

description: ABSTRACT Sanitary metals are objects that, according to the current requirements of the consumer market, must be both corrosion resistant and beautiful, with a shiny mirror appearance. These are usually produced in cast brass because of their easy processing and electrodeposition characteristics. However, to reduce production costs, brass has been replaced by zinc alloys in the manufacture of these components. Zamac has properties such as low melting point compared to brass, which allows the production of thin-walled parts and complex geometries. Pressure injection to obtain zinc hypoeutec alloys (Zamac 5) allows higher productivity associated with better dimensional characteristics, costing about 30% less than brass. This study presents the macro and microstructural characterization of Zamac 5 injected under pressure, relating them to the corrosion resistance of the alloy. For this, saline fog tests and analyzes were performed by scanning electron microscopy, microhardness tests and electrochemical corrosion tests. The Zamac 5 injected under pressure presented non-uniform corrosion in distinct regions of the part when subjected to the aggressive atmosphere. The results also showed that this fact is associated with porosity defects from the alloy manufacturing process. The microhardness of the alloy was also associated with defects from the manufacturing process. Finally, it was evidenced that the electrochemical behavior of the alloy is little influenced by the presence of the defects.
DOI: 10.6084/m9.figshare.14321637
title: Characterization of reinforced aluminum composites with quasicrystalline particles produced by stir casting/rolling

description: ABSTRACT The continuous requirement of lightweight and high performance materials for the aerospace and au-tomotive industries led to the development of composite materials with a metallic matrix, among which aluminum-based composites. The quasicrystals are metallic materials with a complex atomic structure, which results in a combination of physico-mechanical properties similar to those of some fragile ceramics and intermetallic compounds, such as high strength and hardness, high modulus of elasticity, low coefficient of friction and good resistance to wear and corrosion. These properties are very promising for industrial application, but the fragility of the quasicrystals restricts their application as a reinforcement phase in composites, and can replace the traditionally used ceramic reinforcements such as SiC and Al2O3. In the present work, reinforced aluminum matrix composites with 2,5%, 5% and 10% volume of quasicrystalline particles were produced by the stir cast method of stir casting. Subsequent steps of laminating were performed on all aluminum / quasicrystals composites. The quasicrystalline Al61,7Cu25,5Fe12,3Mn0,5 alloy was obtained by conventional melting and subsequent heat treatment. The mill of the quasicrystalline alloy, to obtain powders, was carried out in a high-energy mill. The microstructure of quasicrystals was investigated by X-ray Diffraction and Scanning Electron Microscopy (SEM). The distribution of the quasicrystalline particles in the aluminum matrix and the influence on the hardness of the composites were investigated by SEM and Vickers Microhardness, respectively. The composites presented a good distribution of the quasicrystalline particles in the aluminum matrix, although in some regions the formation of pores and agglomerates occurred. The rolling process promoted a significant increase in hardness in relation to the composites obtained directly from the casting.
DOI: 10.6084/m9.figshare.14321637.v1
title: Characterization of reinforced aluminum composites with quasicrystalline particles produced by stir casting/rolling

description: ABSTRACT The continuous requirement of lightweight and high performance materials for the aerospace and au-tomotive industries led to the development of composite materials with a metallic matrix, among which aluminum-based composites. The quasicrystals are metallic materials with a complex atomic structure, which results in a combination of physico-mechanical properties similar to those of some fragile ceramics and intermetallic compounds, such as high strength and hardness, high modulus of elasticity, low coefficient of friction and good resistance to wear and corrosion. These properties are very promising for industrial application, but the fragility of the quasicrystals restricts their application as a reinforcement phase in composites, and can replace the traditionally used ceramic reinforcements such as SiC and Al2O3. In the present work, reinforced aluminum matrix composites with 2,5%, 5% and 10% volume of quasicrystalline particles were produced by the stir cast method of stir casting. Subsequent steps of laminating were performed on all aluminum / quasicrystals composites. The quasicrystalline Al61,7Cu25,5Fe12,3Mn0,5 alloy was obtained by conventional melting and subsequent heat treatment. The mill of the quasicrystalline alloy, to obtain powders, was carried out in a high-energy mill. The microstructure of quasicrystals was investigated by X-ray Diffraction and Scanning Electron Microscopy (SEM). The distribution of the quasicrystalline particles in the aluminum matrix and the influence on the hardness of the composites were investigated by SEM and Vickers Microhardness, respectively. The composites presented a good distribution of the quasicrystalline particles in the aluminum matrix, although in some regions the formation of pores and agglomerates occurred. The rolling process promoted a significant increase in hardness in relation to the composites obtained directly from the casting.
DOI: 10.5281/zenodo.4639669
title: Elevation data for Reflectors within the CO2 Deposit in Planum Australe, Mars

description: The csv file provides elevation data for the reflectors within the CO<sub>2</sub> deposit in Planum Australe, Mars. Elevation data for the reflectors representing the Martian surface and the bottom of the CO<sub>2</sub> deposit are given, as well as elevation data for the top and bottom reflectors of each BL. The elevations were obtained from our interpretations of 3-dimensional radargrams in SiesWare<sup>TM</sup>. The 3-D data volumes are available at https://sharad.psi.edu/3D/.
DOI: 10.5281/zenodo.4639668
title: Elevation data for Reflectors within the CO2 Deposit in Planum Australe, Mars

description: The csv file provides elevation data for the reflectors within the CO<sub>2</sub> deposit in Planum Australe, Mars. Elevation data for the reflectors representing the Martian surface and the bottom of the CO<sub>2</sub> deposit are given, as well as elevation data for the top and bottom reflectors of each BL. The elevations were obtained from our interpretations of 3-dimensional radargrams in SiesWare<sup>TM</sup>. The 3-D data volumes are available at https://sharad.psi.edu/3D/.
DOI: 10.6084/m9.figshare.14321640
title: Effect of the arc energy on microstructure and corrosion resistance on Inconel 625 weld overlays deposited by GMAW process

description: ABSTRACT Inconel 625 alloy is a highly corrosion resistant nickel-based alloy, largely used as coatings onto a less noble substrates Many techniques have been used for the deposition of Inconel, including welding processes. Traditionally, welding processes that promote low dilution (less contamination of Inconel with the substrate material) have been used, but they present low productivity due to the low deposition rates involved. Thus, this study aims to evaluate the application of Inconel 625 using the GMAW process under different arc energies, which should lead to high deposition rates, but with the inconvenience of promoting high dilution. For this, coatings were deposited using three levels of arc energies and the effects on microstructure and corrosion resistance were evaluated. The macro and microstructural characteristics of the deposited were evaluated by optical microscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). Dilution and secondary dendrite arm spacings were measured and microstructures were evaluated. The corrosion resistance of the deposits was evaluated via cyclic potentiodynamic polarization tests. The results showed that the relationship between arc energy and dilution depended on the weaving amplitude. The arc energy affected the amount of phases, where lower energies produced more refined dendritic structures. In addition, the study showed that corrosion tests conducted at 25 ° C did not promote superficial corrosion in the samples regardless of the arc energy imposed on the coating and that the tests at 60 ° C caused corrosion.
DOI: 10.6084/m9.figshare.14321640.v1
title: Effect of the arc energy on microstructure and corrosion resistance on Inconel 625 weld overlays deposited by GMAW process

description: ABSTRACT Inconel 625 alloy is a highly corrosion resistant nickel-based alloy, largely used as coatings onto a less noble substrates Many techniques have been used for the deposition of Inconel, including welding processes. Traditionally, welding processes that promote low dilution (less contamination of Inconel with the substrate material) have been used, but they present low productivity due to the low deposition rates involved. Thus, this study aims to evaluate the application of Inconel 625 using the GMAW process under different arc energies, which should lead to high deposition rates, but with the inconvenience of promoting high dilution. For this, coatings were deposited using three levels of arc energies and the effects on microstructure and corrosion resistance were evaluated. The macro and microstructural characteristics of the deposited were evaluated by optical microscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). Dilution and secondary dendrite arm spacings were measured and microstructures were evaluated. The corrosion resistance of the deposits was evaluated via cyclic potentiodynamic polarization tests. The results showed that the relationship between arc energy and dilution depended on the weaving amplitude. The arc energy affected the amount of phases, where lower energies produced more refined dendritic structures. In addition, the study showed that corrosion tests conducted at 25 ° C did not promote superficial corrosion in the samples regardless of the arc energy imposed on the coating and that the tests at 60 ° C caused corrosion.
DOI: 10.6084/m9.figshare.14321641
title: Residual stresses induced by milling operations of ABNT 4340 steel under variation of cutting speed, edge angle and heat treatment

description: ABSTRACT Among the various manufacturing processes, it is worth mentioning the machining. Among its operations is milling, which confers characteristics to the surface generated that influence the performance of the component or workpiece. One of these characteristics is the process-induced residual stress. Depending on its character, trative or compressive, intensity and depth affected, it can be beneficial or deleterious. This work investigated the effect of the parameters, cutting speed, edge angle and material condition, ABNT 4340 steel, obtained by annealing and normalizing heat treatments on residual stress induced on the surface. For this, a 2x3x2 factorial design with three replicates was performed. The residual stresses were measured by the hole drilling method. The results obtained were organized and analyzed on the qualitative aspects, profile along the depth, and quantitative. The results indicated that the increase of cutting speed caused the residual stress induced on the surface to be compressive or less tractive. The variation of the edge angle exerted a discrete effect on the residual stress. The milled material in the normalized condition showed compressive residual stresses, on the other hand in the annealed condition trative one. In order to evaluate the quantitative aspect, a variance analysis was performed for the residual stress induced in the depth of 17µm beneath surface. The results showed that the data follow a normal distribution and that the cutting speed and heat treatment factors were found to be significant at the 95% confidence level both in isolation and in the second and third order interactions
DOI: 10.34703/gzx1-9v95/xamu4u/ljbylb
title: ABC-UTC-2016-C2-OU02_FinalReport_FINAL_2020-04-30.pdf

description: Final