Patent Application: US-67341808-A

Abstract:
structures based upon periodic cellular materials that provide a potential for defeating combinations of both air blast loading and ballistic attack either sequentially or simultaneously , or combination of both . the cellular structures may also be configured to meet the stiffness and strength support requirements of particular vehicle or other applications , systems or structures . the armor is therefore potentially able to support normal service loads and defeat blast and ballistic threats when necessary . the structure provides for using efficient load support capabilities of the material in low threat conditions , as well as the ability to modify the system to increase its level protection to a desired or required level . this would reduce the weight of the protection system in normal conditions which reduces vehicle wear and tear , as well as cost savings in fabrication of applicable structures or systems .

Description:
an aspect of various embodiments of the current invention provides , among other things , core combinations from the pcm family of material structures with hard ceramics and / or ballistic fabrics , a superior armor design can be created which also functions as a structural component ( such as a vehicle door or floor ). these structural components then provide , among other things , a light weight solution various blast and ballistic threats . an exemplary approach is based upon multilayering to provide different properties as a function of depth within a sandwich panel . these layers can be added to provide a sandwich panel structure 200 to increase the type and level of protection . one example is shown in fig2 . the sandwich structure 200 comprises a first layer 210 , a second layer 220 with an intermediate member 250 there between to form a core 240 . on opposite sides of the sandwich structure 200 is a front panel 202 and a back panel 222 . this particular , non - limiting example provides a periodic cellular material ( pcm ) panel 200 that combines a square honeycomb in the second layer 220 and pyramidal truss core in the first layer 210 using a thin intermediate face sheet as the intermediate layer 230 . the illustration in fig2 is an example of topology multilayering . it should be appreciated that any combination of cores with only open , only closed or combinations of open and closed cells could be configured from either a single material or different materials for each layer and face sheet within the context of the present invention . the closed cell structure has very good air blast resistance because its core is stretch resistant and compression of entrapped gases or combinations of gases and fluids provides a resisting force to core crushing during localized impact . under dynamic blast conditions , core crushing compresses the air / fluid inside the cubic volume of the individual cells offering reactive resistance to wall compression and delaying the buckling / wrinkling of the individual web members of the square honeycomb cell . thus the time dependent energy absorption come from densification through compressing air inside the individual honeycomb cell combined with severe plastic deformation of the cell walls . strain and strain rate hardening under dynamic loading rate can also be exploited by for additional energy dissipation by appropriate selection of the base material ( any metal , polymer , ceramic or composite is envisioned here ). the core density and material can be adjusted to make it the weaker layer in the system . this structure , especially when it contains vapor / fluid ( or particulate solid / liquid / gaseous ) mixtures , can then also provide significant mitigation of the shock waves created by projectile impacts . the second layer 220 shown in fig2 is a pyramidal lattice core sandwich panel but it could be any open cell structure . its strength and crush resistance can be controlled by the cell relative density , the angle of the trusses , the second moment of inertia of the trusses and the material used to make the core . it can be designed to crush at a higher or lower level of blast pressure than the lower panel providing a means for selecting the depth within the functionally graded panel where blast energy dissipation occurs . the strong layer in the various system associated with a plurality of embodiments of the present invention disclosed can also provide a stiff , strong backing for supporting other structures that help defeat a ballistic threat . by attaching ceramic or ballistic fabrics to the front or back face of the two layer panel or by filling the truss space with ceramic , ballistic fabrics or hard polymers , the ballistic performance of the functionally graded sandwich panel can be significantly elevated without reducing the blast resistance or load supporting functionality of the structure . the truss member can also interact and slow some projectiles helping to dissipate their transverse momentum . an example of such hybrid armor with a ceramic face shield is shown in fig3 . the sandwich structure 300 comprises a first layer 310 , a second layer 320 with an intermediate member 350 there between to form a core 340 . on opposite sides of the sandwich structure 300 is a front panel 302 and a back panel 322 . this particular , non - limiting example provides a periodic cellular material ( pcm ) panel 300 that combines a square honeycomb in the second layer 220 and pyramidal truss core in the first layer 310 using a thin intermediate face sheet as the intermediate layer 250 . further a ballistic protection layer 304 is mounted to the front panel 302 for additional ballistic protection . an exemplary material for the ballistic protection layer 304 is ceramic , and other possible materials include , but not limited thereto , the following : ceramic - fiber reinforced ceramics with fibers s - 2 , sic fibers ; polymer fiber reinforced composites with fibers such as polyethylene , polypropolyne ; metallic plates made from intermetallics such as titanium boride , other advanced metals harder than conventional roll hardened steels . the ceramic shield can be attached to the front or back face sheet of the panel depending on the requirement . contrary to the illustration of fig3 , if the square honeycomb core of the second layer 320 is placed on the front to absorb the impulse from a blast , fracture of the ceramic is prevented and the ceramic shield on the back side remains suitable for projectile protection . on the other hand , consistent with the illustration of fig3 , if the ceramic is on the front surface , the sandwich panel provides a rigid backing increasing the efficiency of the ceramic during ballistic defeat . the sandwich panel can then serve as a fragment arrest system . a second design embodiment envisioned in this invention utilizes an all open cell core for both the first layer and second layer . this could be a single or multilayer structure with open or solid intermediate face sheets in the latter case . this design can employ multilayer pyramidal , tetrahedral or any other tusscore / lattice structures including any of those shown in fig1 . turning to fig4 , fig4 provides a photographic depiction of the sandwich structure 400 having open cell core 440 for both the first layer 410 and second layer 420 , both of which are pyramidal truss core layers ; and an intermediate member 450 there between to form a core 440 . on opposite sides of the sandwich structure 400 is a front panel 402 and a back panel 422 . further a ballistic protection layer 404 is mounted to the front panel 402 for additional ballistic protection . an exemplary material for the ballistic protection layer 304 is ceramic , and other possible materials include , but not limited thereto , the following : ceramic - fiber reinforced ceramics with fibers s - 2 , sic fibers ; polymer fiber reinforced composites with fibers such as polyethylene , polypropolyne ; metallic plates made from intermetallics such as titanium boride , other advanced metals harder than conventional roll hardened steels . in an embodiment the ballistic protection layer 404 may be disposed or located within a honeycomb type cell 406 . while only one cell is illustrated it is envisioned that multiple cells may be implemented to contain the material . it should also be appreciated that a variety of cell structures may be implemented other than honeycomb as desired or required such as hexagonal , square , triangular , cylindrical etc . turning to fig5 , fig5 provides a photographic depiction of the sandwich structure 500 having open cell core 540 for both the first layer 510 and second layer 520 , both of which are pyramidal truss core layers ; and an intermediate member 550 there between . further , an additional layer 530 is provided before the first layer 510 ( or second layer , for example ) to form a core 540 , with an intermediate member 550 there between the first layer and additional layer . on opposite sides of the sandwich structure 500 is a front panel 502 and a back panel 522 . further a ballistic protection layer 504 is mounted to the front panel 502 for additional ballistic protection . an exemplary material for the ballistic protection layer 504 is ceramic , and other possible materials include , but not limited thereto , the following : ceramic - fiber reinforced ceramics with fibers s - 2 , sic fibers ; polymer fiber reinforced composites with fibers such as polyethylene , polypropolyne ; metallic plates made from intermetallics such as titanium boride , other advanced metals harder than conventional roll hardened steels . still referring to fig5 , the exemplary and non - limiting illustration demonstrates a three layered pyramidal trusscore structure 500 with ceramic rods 544 inserted into two layers 510 , 520 to provide cross linked grid pattern . a polymeric layer 530 is shown on the front of the structure to provide impact protection and reduce the probability of face sheet failure during dynamic loading . turning to fig6 , fig6 provides a photographic depiction of the sandwich structure 600 having open cell core 640 for both the first layer 610 and second layer 620 , both of which are pyramidal truss core layers ; and an intermediate member 650 there between . on opposite sides of the sandwich structure 600 is a front panel 602 and a back panel 622 . further a ballistic protection layer 604 is mounted to the front panel 602 for additional ballistic protection . an exemplary material for the ballistic protection layer 604 is ceramic , and other possible materials include , but not limited thereto , the following : ceramic - fiber reinforced ceramics with fibers s - 2 , sic fibers ; polymer fiber reinforced composites with fibers such as polyethylene , polypropolyne ; metallic plates made from intermetallics such as titanium boride , other advanced metals harder than conventional roll hardened steels . still referring to fig6 , the exemplary and non - limiting illustration demonstrates a two layer pyramidal trusscore panel structure 600 with cylindrical ceramic rods 644 inserted into the one layer 610 . it is also possible to incorporate the interstitial housing 644 such as ceramic components ( other applicable materials include ceramic - fiber reinforced ceramics with fibers s - 2 , sic fibers ; polymer fiber reinforced composites with fibers such as polyethylene , polypropolyne ; metallic plates made from intermetallics such as titanium boride , other advanced metals harder than conventional roll hardened steels .) inside the core . examples of these designs are shown in fig5 and 6 . the interstitial housing s 544 , such as ceramic components used for these designs may be for example , prismatic or circular rods that can either closely or loosely fit within lattice pores . other interstitial housing shapes may be employed within the context of the invention and as discussed herein . the ceramic rods can be encased in a metallic tube casing to provide enhanced ballistic performance and reduce mechanical shock that can be transmitted to the rods . as will be discussed in further detail herein , polymers , metals , ceramic powders and their combinations can also be used to fully or partially fill the remaining void spaces in the structure of the layers 510 , 610 , 510 , 610 , and 530 . as will be discussed in further detail herein , polymers or polymer fabrics can also be added to the system to modify ballistic responses and / or interact in beneficial ways with air blast created shock waves . fig8 schematically illustrate various embodiments of aspects of aspects of the present invention sandwich structure 800 comprises a first layer 810 forming a core 840 and on opposite sides of the sandwich structure 800 is a front panel 802 and a back panel 822 . fig8 ( a ) illustrates the sandwich structure 800 that is a generally empty lattice structure wherein the first layer 810 is an open - cell lattice structure comprising a plurality or an array of pyramidal trusses 812 . fig8 ( b ) illustrates the sandwich structure 800 that is a lattice structure wherein the first layer 810 is an open - cell lattice structure comprising a plurality or an array of pyramidal trusses 812 . a filler portion 842 , such as an elastomer ( or other desired or required filler material ) fills the void or volume of the open core . the elastomer may be polyurethane , polyeuria or other desired polymers or materials or other filler materials . fig8 ( c ) illustrates the sandwich structure 800 that is similar to the embodiment disclosed in fig8 ( b ) . additionally , a kevlar substrate 852 is disposed in communication with the inner sides of front panel 802 and back panel 822 . the kevlar substrate may be kevlar fabric , s - 2 fabric , dynema fabric , aramid fabric , or other desired materials or structures . the elastomer ( or other desired or required material ) fills the void or volume of the open core of the present embodiment . fig8 ( d ) illustrates the sandwich structure 800 that is similar to the embodiment disclosed in fig8 ( b ) further including interstitial housings 844 disposed so as to span across the sandwich structure 800 , or at least portions of the sandwich structure as desired or required . the interstitial housings may be ceramic prisms or other suitable materials or structures . the interstitial housings may comprise : ceramic - fiber reinforced ceramics with fibers s - 2 , sic fibers ; polymer fiber reinforced composites with fibers such as polyethylene , polypropolyne ; metallic plates made from intermetallics such as titanium boride , other advanced metals harder than conventional roll hardened steels the interstitial housings 844 conform to the geometry or void created by the trusses 812 of the layer 810 . the conformance is designed for optimizing structural integrity and ballistic and blast mitigation as desired or required . the elastomer ( or other desired or required material ) fills the void or volume of the open core of the trusses and interstitial housings . fig8 ( e ) illustrates the sandwich structure 800 that is similar to the embodiment disclosed in fig8 ( c ) having not only the kevlar substrate 852 disposed in communication with the inner sides of front panel 802 and back panel 822 , but also interstitial housings 844 disposed so as to span across the sandwich structure 800 , or at least portions of the sandwich structure as desired or required . the interstitial housings 844 conform to the geometry or void created by the trusses 812 of the layer 810 . the conformance is designed for optimizing structural integrity and ballistic and blast mitigation as desired or required . the elastomer ( or other desired or required material ) fills the void or volume of the open core of the trusses , kevlar substrate , and the interstitial housings . fig9 provides photographic depictions of cross - sectional views of a prototype exemplary embodiment of the present invention sandwich structure 900 comprising a first layer 910 forming a core 940 and on opposite sides of the sandwich structure 900 is a front panel 902 and a back panel 922 . referring to the cross - sectional view of fig9 ( b ) , visible is kevlar substrate 952 disposed in communication with the inner sides of front panel 902 and back panel 922 , the interstitial housings 944 disposed so as to span across the sandwich structure 900 , or at least portions of the sandwich structure as desired or required . the interstitial housings 944 conform to the geometry or void created by the trusses 912 of the layer 910 . a small portion of the elastomer 942 ( or other desired or required material or filler portion or material ) is visible that is provided to fill the void or volume of the open core of the trusses 912 , kevlar substrate , and / or the interstitial housings . referring to the cross - sectional view of fig9 ( a ) , much less is visible compared to the cross - sectional view of fig9 ( b ) . for instance , visible in fig9 ( a ) is front panel 902 and back panel 922 , elastomer 942 ( or other desired or required material or filler portion or material ) is visible that fills the void or volume of the open core of the trusses 912 , whereby only segments of the trusses are visible . fig1 ( a ) provides a schematic perspective view of an exemplary embodiment of the present invention sandwich structure 1000 comprising a first layer 1010 , a second layer 1020 with an intermediate member 1050 there between to form a core 1040 . on opposite sides of the sandwich structure 1000 is a front panel 1002 and a back panel 1022 . it should be appreciated that the front panel 1002 may be a light metal / composite face sheet ( e . g ., outer face facesheet ) or other material or structure as desired or required . it should be appreciated that the first layer 1010 may be an empty layer designed to mitigate blast over pressure . it should be appreciated that the first and second layers 1010 , 1020 , may be open - cell lattice structures made up of a plurality of trusses being pyramidal lattice type . other types of cellular or lattice structures may be implemented as desired or required . it should be appreciated that the back panel 1022 may be a light metal / composite face sheet ( e . g ., back facesheet ) or other material or structure as desired or required . still referring to fig1 ( a ) , an intermediate layer 1050 is provided as well as a ballistic substrate 1054 mounted or in communication with the back panel 1022 and the bottom side of the intermediate layer 1050 for additional ballistic protection . it should be appreciated that one or more of the ballistic substrate 1054 may be a kevlar substrate . it should be appreciated that one or more of the ballistic substrate 1054 may be a piezoelectric active damper system or device . it should be appreciated that one or more of the ballistic substrate 1054 may be a piezoelectric power generation system or device . still referring to fig1 ( a ) , further provided are interstitial housings 1044 disposed so as to span across the sandwich structure 1000 , or at least portions of the sandwich structure as desired or required . the interstitial housings 1044 may be ceramic prisms or other suitable materials or structures . the interstitial housings may a variety of materials including b 4 c or sic ceramic , but not limited thereto . fig1 ( b ) provides an enlarged cross - sectional partial view of the interstitial housings 1044 . the housing 1044 may have an encasement 1046 surrounding it or a portion of it . the encasement 1046 may be , for example but not limited thereto , high coefficient of thermal expansion ( cte ) of metal or the like compresses the ceramic after fabrication . still referring to fig1 ( a ) , further an elastomer ( or other desired or required material ) is provided to fill the void or volume of the open core of the trusses 1012 , ballistic substrate 1054 , and the interstitial housings 1044 . the elastomer , material or other material may be tailored for optimum results of the structure and function thereof . the elastomer or fill material 1042 may be tailored ( e . g ., fills all voids or as desired or required ). these aforementioned embodiments illustrate the flexibility of having a variety of fabrication and structural approaches . for instance , depending on the mass density requirements the metallic panels can be fabricated with steel , aluminum alloy , titanium and magnesium alloy to meet the required performance . the ceramic component shapes can be of any variety of oxides , nitrides , and / or carbides processed by hot pressing or reaction bonding / sintering methods . these can be permanently integrated into the structure or added in the field when required . the hard materials placed within the cores can be maintained in place by a variety of means including potting in foam or polymers , or with small particle size granular materials which also provide additional blast protection capabilities . in summary , an aspect of various embodiments of the present invention provide a family of hybrid periodic cellular materials structures that are structurally strong and capable of mitigating high kinetic energy blast waves and high velocity projectiles . an aspect utilizes multilayered cores topologies and materials that exhibit high levels of energy absorption through plastic deformation , and ability to deflect the incident projectile so as to reduce the momentum forces . these highbred composite armor structures can be manufactures by combinations of metals , ceramics , and polymers . lightweight cellular structures , both stochastic and periodic , can be manufactured from numerous metals and metal alloys by a wide variety of vapor -, liquid - and solid - state processes . the properties of these cellular structures depend upon the properties of the base metal alloy , the relative density of the structure , and the distribution of material within the structure ( i . e . stochastic , periodic , open or closed cell , cell size , etc .). periodic cellular metals can be manufactured by various methods including : investment casting , lattice block construction , constructed metal lattice and metal textile lay - up techniques . these techniques for manufacturing periodic cellular metals enable the metal topology to be controlled that efficient load supporting structures can be made . they are especially useful when used as cores of sandwich panels . exemplary embodiment of present invention herein provides , among other things , a process , which utilizes non - woven wire fabrication routes for the manufacture of periodic cellular cores . this exemplary process associated with the various embodiments and inventive concept allows the strength of the structure to be precisely controlled by the relative density of the structure , which is a function of the wire and cell size and shape as well as the stacking sequence . in addition , these materials lend themselves to multifunctional integration for heat transfer , power storage , energy absorption , etc applications . also , this manufacturing technique should be economically viable when compared with other periodic cellular metals manufacturing technologies . it should be appreciated that the various embodiments of the present invention sandwich structure or any sub - combinations thereof may be fabricated utilizing a number of manufacturing methods . for instance , some exemplary manufacturing methods of the sandwich structure or any components thereof may include the following methods or combination thereof : brazing , welding , soldering , and near neat shape or net shape fabrication using techniques such as extrusion , or casting . for example , a method may produce the truss core structures utilizing extrusion that provide very good nodal strength and resultant performance . it should be appreciated that various aspects of embodiments of the present method , system , devices , article of manufacture , and compositions may be implemented with the following methods , systems , devices , article of manufacture , and compositions disclosed in the following u . s . patent applications , u . s . patents , and pct international patent applications and are hereby incorporated by reference herein and co - owned with the assignee : international application no . pct / us2008 / 060637 entitled “ heat - managing composite structures ,” filed apr . 17 , 2008 . international application no . pct / us2007 / 022733 entitled “ manufacture of lattice truss structures from monolithic materials ,” filed oct . 26 , 2007 . international application no . pct / us2007 / 012268 , entitled “ method and apparatus for jet blast deflection ,” filed may 23 , 2007 . international application no . pct / us04 / 04608 , entitled “ methods for manufacture of multilayered multifunctional truss structures and related structures there from ,” filed feb . 17 , 2004 , and corresponding u . s . application ser . no . 10 / 545 , 042 , entitled “ methods for manufacture of multilayered multifunctional truss structures and related structures there from ,” filed aug . 11 , 2005 . international application no . pct / us03 / 27606 , entitled “ method for manufacture of truss core sandwich structures and related structures thereof ,” filed sep . 3 , 2003 , and corresponding u . s . application ser . no . 10 / 526 , 296 , entitled “ method for manufacture of truss core sandwich structures and related structures thereof ,” filed mar . 1 , 2005 . international patent application serial no . pct / us03 / 27605 , entitled “ blast and ballistic protection systems and methods of making same ,” filed sep . 3 , 2003 international patent application serial no . pct / us03 / 23043 , entitled “ method for manufacture of cellular materials and structures for blast and impact mitigation and resulting structure ,” filed jul . 23 , 2003 international application no . pct / us03 / 16844 , entitled “ method for manufacture of periodic cellular structure and resulting periodic cellular structure ,” filed may 29 , 2003 , and corresponding u . s . application ser . no . 10 / 515 , 572 , entitled “ method for manufacture of periodic cellular structure and resulting periodic cellular structure ,” filed nov . 23 , 2004 . international application no . pct / us02 / 17942 , entitled “ multifunctional periodic cellular solids and the method of making thereof ,” filed jun . 6 , 2002 , and corresponding u . s . application ser . no . 10 / 479 , 833 , entitled “ multifunctional periodic cellular solids and the method of making thereof ,” filed dec . 5 , 2003 . international application no . pct / us01 / 25158 entitled “ multifunctional battery and method of making the same ,” filed aug . 10 , 2001 , u . s . pat . no . 7 , 211 , 348 issued may 1 , 2007 and corresponding u . s . application ser . no . 11 / 788 , 958 , entitled “ multifunctional battery and method of making the same ,” filed apr . 23 , 2007 . international application no . pct / us01 / 22266 , entitled “ method and apparatus for heat exchange using hollow foams and interconnected networks and method of making the same ,” filed jul . 16 , 2001 , u . s . pat . no . 7 , 401 , 643 issued jul . 22 , 2008 entitled “ heat exchange foam ,” and corresponding u . s . application ser . no . 11 / 928 , 161 , “ method and apparatus for heat exchange using hollow foams and interconnected networks and method of making the same ,” filed oct . 30 , 2007 . international application no . pct / us01 / 17363 , entitled “ multifunctional periodic cellular solids and the method of making thereof ,” filed may 29 , 2001 , and corresponding u . s . application ser . no . 10 / 296 , 728 , entitled “ multifunctional periodic cellular solids and the method of making thereof ,” filed nov . 25 , 2002 . it should be appreciated that various aspects of embodiments of the present method , system , devices , article of manufacture , and compositions may be implemented with the following methods , systems , devices , article of manufacture , and compositions disclosed in the following u . s . patent applications , u . s . patents , and pct international patent applications and are hereby incorporated by reference herein and co - 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recited detailed description and drawings of certain exemplary embodiments . it should be understood that numerous variations , modifications , and additional embodiments are possible , and accordingly , all such variations , modifications , and embodiments are to be regarded as being within the spirit and scope of this application . for example , regardless of the content of any portion ( e . g ., title , field , background , summary , abstract , drawing figure , etc .) of this application , unless clearly specified to the contrary , there is no requirement for the inclusion in any claim herein or of any application claiming priority hereto of any particular described or illustrated activity or element , any particular sequence of such activities , or any particular interrelationship of such elements . moreover , any activity can be repeated , any activity can be performed by multiple entities , and / or any element can be duplicated . further , any activity or element can be excluded , the sequence of activities can vary , and / or the interrelationship of elements can vary . unless clearly specified to the contrary , there is no requirement for any particular described or illustrated activity or element , any particular sequence or such activities , any particular size , speed , material , dimension or frequency , or any particularly interrelationship of such elements . accordingly , the descriptions and drawings are to be regarded as illustrative in nature , and not as restrictive . moreover , when any number or range is described herein , unless clearly stated otherwise , that number or range is approximate . when any range is described herein , unless clearly stated otherwise , that range includes all values therein and all sub ranges therein . any information in any material ( e . g ., a united states / foreign patent , united states / foreign patent application , book , article , etc .) that has been incorporated by reference herein , is only incorporated by reference to the extent that no conflict exists between such information and the other statements and drawings set forth herein . in the event of such conflict , including a conflict that would render invalid any claim herein or seeking priority hereto , then any such conflicting information in such incorporated by reference material is specifically not incorporated by reference herein .