Personal armor resistant to sharp or pointed weaponry

Abstract

According to exemplary inventive practice, a personal armor system includes a textile-based layer not exceeding ½-half-inch thickness, and an elastomeric coating not exceeding ⅛-inch thickness. The textile-based layer includes a fiber reinforcement and a resin binder. The combined areal density of the textile-based layer and the elastomeric coating does not exceed 2.5 psf. According to a first mode of inventive practice, the elastomeric coating is essentially a strain-rate-sensitivity-hardening elastomer, and the areal density of the textile-based layer does not exceed 2.3 psf. According to a second mode of inventive practice, the elastomeric coating is essentially a microparticle-filled strain-rate-sensitivity-hardening elastomeric matrix material, and the areal density of the textile-based layer does not exceed 1.7 psf. The microparticles (e.g., spherical glass microparticles) do not exceed, by weight, 30 percent of the strain-rate-sensitivity-hardening elastomeric matrix material. The textile-based layer affords ballistic protection; the elastomeric coating affords protection against sharp/pointed objects.

Claims

1. A composite armor system comprising: a ballistic fabric-based backing layer, said ballistic fabric-based backing layer having an areal density of about 1.8 to about 2.3 pounds per square foot, having a thickness of about 0.2 to about 0.5 inch, and being resistant to impacts by ballistic objects; and an elastomeric coating strike-face layer, said elastomeric coating strike-face layer consisting essentially of a strain-rate-sensitivity-hardening elastomer, having a thickness of about 0.06 to about 0.12 inch, and being resistant to impacts by sharp or pointed objects; said elastomeric coating strike-face layer covering at least one area of said ballistic fabric-based backing layer wherein, in said at least one area of said ballistic fabric-based backing layer: said covering has been effected by a process including bonding an elastomeric coating material onto said ballistic fabric-based backing layer whereby approximately none of said elastomeric material infiltrates into said ballistic-fabric-based backing layer; the ratio of said thickness of said elastomeric coating strike-face layer to said thickness of said ballistic fabric-based backing layer is from about 0.15 to about 0.35; said elastomeric coating strike-face layer and said ballistic fabric-based backing layer, in combination, have an areal density no greater than approximately 2.5 pounds per square foot; wherein, upon said impact by said sharp or pointed object, said elastomeric coating strike-face layer undergoes strain-rate-sensitivity hardening that impedes said sharp or pointed object.

2. The composite armor system of claim 1, wherein said elastomeric coating strike-face layer has a thickness of about 0.08 to about 0.10 inch.

3. The composite armor system of claim 1, wherein said elastomeric coating strike-face layer includes a polyurea.

4. The composite armor system of claim 1, wherein: said elastomeric coating strike-face layer includes an elastomeric material selected from the group of elastomeric materials consisting of polyurea, polyurethane, and a mixture of polyurea and polyurethane; said ballistic fabric-based backing layer includes a fabric material selected from the group of fabric materials consisting of aramid, polyethylene, polyamide, polyester, polybenzobisoxazole, and glass.

5. The composite armor system of claim 4, wherein said elastomeric coating strike-face layer has a thickness of about 0.08 to about 0.10 inch.

6. The composite armor system of claim 4, wherein said elastomeric coating strike-face layer includes a polyurea.

7. The composite armor system of claim 2, wherein: said elastomeric coating strike-face layer includes an elastomeric material selected from the group of elastomeric materials consisting of polyurea, polyurethane, and a mixture of polyurea and polyurethane; said ballistic fabric-based backing layer includes a fabric material selected from the group of fabric materials consisting of aramid, polyethylene, polyamide, polyester, polybenzobisoxazole, and glass.

8. A method for making or enhancing armor, said method comprising covering at least one area of a ballistic fabric-based material with an elastomeric coating material, said elastomeric coating material consisting essentially of a strain-rate-sensitivity-hardening elastomer, said covering of said at least one area including bonding said elastomeric coating material onto said ballistic fabric-based material, said covering of said at least one area thereby forming an armor system including a strike-face layer and a backing layer, said strike-face layer at least substantially constituted by said elastomeric coating material, said backing layer at least substantially constituted by said ballistic fabric-based material, wherein said covering of said at least one area is performed so that, in said at least one area: said strike-face layer has a thickness of about 0.06 to about 0.12 and is resistant to impacts by ballistic objects; said backing layer has an areal density of about 1.8 to about 2.3 pounds per square foot, has a thickness of about 0.2 to about 0.5 inch, and is resistant to impacts by sharp or pointed objects; the ratio of said thickness of said strike-face layer to said thickness of said backing layer is from about 0.15 to about 0.35; said strike-face layer and said backing layer, in combination, have an aerial density no greater than approximately 2.5 pounds per square foot; upon said impact by said sharp or pointed object, said strike-face layer undergoes strain-rate-sensitivity hardening that impedes said sharp or pointed object, resulting in occurrence of one of the following: said sharp or pointed object does not penetrate said strike-face layer into said backing layer, wherein the strain-rate-sensitivity-hardening of said strike-face layer prevents said penetration; said sharp or pointed object at least partially penetrates said strike-face layer into said backing layer and to an at least substantial degree does not penetrate beyond said backing layer, wherein the strain-rate-sensitivity-hardening of said strike-face layer mitigates said at least partial penetration in terms of at least one of breakage and velocity reduction of said sharp or pointed object.

9. The method for making or enhancing armor as recited in claim 8, wherein said covering of said at least one area is performed so that, in said at least one area, said strike-face layer has a thickness of about 0.08 to about 0.10 inch.

10. The method for making or enhancing armor as recited in claim 8, wherein: said strike-face layer includes an elastomeric material selected from the group of elastomeric materials consisting of polyurea, polyurethane, and a mixture of polyurea and polyurethane; said backing layer includes a fabric material selected from the group of fabric materials consisting of aramid, polyethylene, polyamide, polyester, polybenzobisoxazole, and glass.

11. The method for making or enhancing armor as recited in claim 8, wherein said covering of said at least one area is performed so that, in said at least one area: a portion of said strike-face layer infiltrates said backing layer; and the infiltrated said at least one area represents an infiltration region including said strike-face layer, said infiltration region having a thickness no less than approximately 10 percent of the thickness of said backing layer.

12. The method for making or enhancing armor as recited in claim 6, wherein said covering of said at least one area is performed so that, in said at least one area, said strike-face layer has a thickness of about 0.08 to about 0.10 inch.

13. The method for enhancing armor as recited in claim 11, wherein: said strike-face layer includes an elastomeric material selected from the group of elastomeric materials consisting of polyurea, polyurethane, and a mixture of polyurea and polyurethane; said backing layer includes a fabric material selected from the group of fabric materials consisting of aramid, polyethylene, polyamide, polyester, polybenzobisoxazole, and glass.

14. The method for making or enhancing armor as recited in claim 8, wherein said covering of said at least one area is performed so that, in said at least one area, approximately none of said strike-face layer infiltrates said backing layer.

15. A composite armor system comprising: a ballistic fabric-based backing layer, said ballistic fabric-based backing layer having an areal density of about 1.8 to about 2.3 pounds per square foot, having a thickness of about 0.2 to about 0.5 inch, and being resistant to impacts by ballistic objects; and an elastomeric coating strike-face layer, said elastomeric coating strike-face layer consisting A essentially of a strain-rate-sensitivity-hardening elastomer, having a thickness of about 0.06 to about 0.12 inch, and being resistant to impacts by sharp or pointed objects; said elastomeric coating strike-face layer covering at least one area of said ballistic fabric-based backing layer wherein, in said at least one area of said ballistic fabric-based backing layer: said covering has been effected by a process including bonding an elastomeric coating material onto said ballistic fabric-based backing layer whereby a portion of said elastomeric material infiltrates into said ballistic-fabric-based backing layer, thereby forming an infiltration region representing an intersection of said elastomeric coating strike-face layer and said ballistic fabric-based backing layer, said infiltration region extending into said ballistic fabric-based backing layer no less than approximately 10 percent of the thickness of said ballistic fabric-based backing layer; the ratio of said thickness of said elastomeric coating strike-face layer to said thickness of said ballistic fabric-based backing layer is from about 0.15 to about 0.35; said elastomeric coating strike-face layer and said ballistic fabric-based backing layer, in combination, have an areal density no greater than approximately 2.5 pounds per square foot; wherein, upon said impact by said sharp or pointed object, said elastomeric coating strike-face layer undergoes strain-rate-sensitivity hardening that impedes said sharp or pointed object.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will now be described, by way of example, with reference to the accompanying drawings, wherein like numbers indicate same or similar parts or components, and wherein:

(2) FIG. 1 is a cross-sectional view of an embodiment of inventive armor. The inventive armor includes a strain-rate-sensitivity-hardening elastomer coating (such as a polyurea) and a ballistic fabric (such as a Kevlar® material). FIGS. 1 through 4 are similar cross-sectional views of various embodiments of inventive armor.

(3) FIG. 2 shows an embodiment of inventive armor that includes a strain-rate-sensitivity-hardening elastomer coating (such as a polyurea) and a ballistic fabric (such as a Kevlar® material), wherein a portion of the elastomer coating infiltrates the ballistic fabric.

(4) FIG. 3 shows an embodiment of inventive armor that includes a particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coating (such as a polyurea filled with microparticles, e.g., glass microspheres) and a ballistic fabric (such as a Kevlar® material).

(5) FIG. 4 shows an embodiment of inventive armor that includes a particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coating (such as a polyurea filled with microparticles, e.g., glass microspheres) and a ballistic fabric (such as a Kevlar® material), wherein a portion of the particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coating infiltrates the ballistic fabric.

(6) FIGS. 5 through 8 are cutaway top plan views of the embodiments of inventive armor shown in FIGS. 1 through 4, respectively.

(7) FIGS. 9 through n are representations, based on photographic images, of three broadhead arrows that were used by the present inventors in their testing of the present invention.

(8) FIG. 12 is a diagram illustrating, by way of example of conventional ballistic armor, an intact penetration of an impelled broadhead arrow through a ballistic fabric.

(9) FIG. 13 is a diagram illustrating, by way of example of an inventive ballistic armor, a ricochet of an impelled broadhead arrow off of a strain-rate-sensitivity-hardening elastomer coating coupled with ballistic fabric.

(10) FIG. 14 is a diagram illustrating, by way of example of an inventive ballistic armor, a ricochet of an impelled broadhead arrow off of a particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coupled with ballistic fabric. FIGS. 13 and 14 are similar.

(11) FIG. 15 is a diagram illustrating, by way of example of an inventive ballistic armor, a broken penetration of an impelled broadhead through a strain-rate-sensitivity-hardening elastomer coating coupled with ballistic fabric.

(12) FIG. 16 is a diagram illustrating, by way of example of an inventive ballistic armor, a broken penetration of an impelled broadhead through a particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coupled with ballistic fabric. FIGS. 15 and 16 are similar.

(13) FIG. 17 is a table setting forth various respective thicknesses of an elastomeric coating and a ballistic fabric, and various corresponding thickness-to-thickness ratios, in accordance with exemplary practice of the present invention.

(14) FIG. 18 is a table setting forth the elastomeric coating thickness ranges and the ballistic fabric areal density ranges for two modes of inventive practice, viz., (i) an inventive armor system including a strain-rate-sensitivity-hardening elastomer coating, and (ii) an inventive armor system including a particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coating.

DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

(15) Referring now to FIGS. 1 through 8, according to exemplary practice of the present invention an elastomeric coating forms an integral shell that resists penetration by sharp and pointed objects. Depending on the inventive embodiment, the elastomeric coating can be: either (i) an unfilled strain-rate-sensitivity-hardening elastomer (e.g., polyurea or other polymer) coating 10, such as shown in FIGS. 1, 2, 5, and 6; or (ii) a particle-filled strain-rate-sensitivity-hardening elastomeric (e.g., polyurea or other polymer) matrix coating 30, such as shown in FIGS. 3, 4, 7, and 8.

(16) The elastomer (e.g., polyurea) in elastomeric coating 10 or 30, according to exemplary inventive practice, is a polymer from a class of polymers that exhibit highly rate-sensitive behavior over a wide range of velocities. The physical properties of a polyurea or other polymer that may be suitably used for inventive practice of an elastomeric coating 10 or an elastomeric coating 30 are disclosed in the aforementioned U.S. Pat. Nos. 9,869,533 B2, 8,580,387 B1, 7,946,211 B1, 7,938,053 B1, 7,794,808 B2, 7,300,893 B2, and 7,114,764 B1, each of which is incorporated by reference in the instant disclosure.

(17) As the terms are used herein, (i) a “strain-rate-sensitivity-hardening elastomer coating” and (ii) a “particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coating” are two types of “elastomeric coating” that are used in accordance with exemplary practice of the present invention. Otherwise expressed, (i) a “strain-rate-sensitivity-hardening elastomer” and (ii) a “particle-filled strain-rate-sensitivity-hardening elastomeric matrix material” are two types of “elastomeric material” that is used in accordance with exemplary practice of the present invention. A strain-rate-sensitivity-hardening elastomer coating is unadulterated, i.e., unfilled. According to exemplary inventive practice of a particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coating, the particles are microparticles, for instance, spherical microparticles such as made of a glass material. A particle-filled strain-rate-sensitivity-hardening elastomeric matrix material is a strain-rate-sensitivity-hardening elastomer coating that is filled with particles to a weight that, according to exemplary inventive practice, is 50% or less of the weight of the strain-rate-sensitivity-hardening elastomer material.

(18) For instance, by way of example of inventive practice, a polyurea contains a quantity of particles filled (e.g., spherical glass microparticles) to a weight that is 30% or less of the weight of the polyurea. According to exemplary embodiments of the present invention, a particle-filled strain-rate-sensitivity-hardening elastomeric matrix material represents a combination of a strain-rate-sensitivity-hardening elastomer material and a quantity (e.g., multiplicity) of particles (e.g., microparticles) wherein the quantity of particles has a weight in the approximate range of 10% to 30% of the weight of the strain-rate-sensitivity-hardening elastomer material.

(19) As shown in FIGS. 1 and 5, a relatively thin strain-rate-sensitivity-hardening elastomer (e.g., polyurea) coating layer 10 is bonded onto the top surface of a ballistic-fabric-based component 20 “backing,” thereby establishing an interface 12 therebetween in a layered configuration of inventive armor. Strain-rate-sensitivity-hardening elastomer coating 10 at least substantially consists of strain-rate-sensitivity-hardening elastomer material 100, and is thin in comparison with the thickness of ballistic-fabric-based layer component 20. Interface 12 represents a demarcation between elastomeric coating layer 10 and ballistic-fabric-based component 20. FIGS. 1 and 5 thus illustrate an inventive embodiment in which there is a clear delineation (separation) between elastomeric coating layer 10 and ballistic-fabric-based component 20. Examples of commercially available fabrics that may be suitably used for inventive practice of ballistic-fabric-based component 20 include Kevlar®, Twaron®, Spectra®, Dyneema®, Cordura®, and Zylon®.

(20) In contrast to FIGS. 1 and 5, FIGS. 2 and 6 illustrate an inventive embodiment characterized by a degree of infiltration (permeation) of the strain-rate-sensitivity-hardening elastomer coating 10 into the ballistic-fabric-based layer component 20. Accordingly, strain-rate-sensitivity-hardening elastomer coating 10 and ballistic-fabric-based layer component 20 overlap (intersect) to form an infiltration region 21, which represents both a sublayer of strain-rate-sensitivity-hardening elastomer coating 10 and a sublayer of ballistic-fabric-based layer component 20. Infiltration region 21 includes strain-rate-sensitivity-hardening elastomer material 100 and ballistic-fabric-based material 200.

(21) It may be considered that, as shown in FIGS. 2 and 6, strain-rate-sensitivity-hardening elastomer coating 10 includes two adjacent sublayers, viz., an elastomeric sublayer n and an infiltration sublayer 21. Similarly, it may be considered that ballistic-fabric-based layer component 20 includes two adjacent sublayers, viz., a fabric-based sublayer 22 and an infiltration sublayer 21. Infiltration region/sublayer 21 is a combination including elastomeric coating 10 and ballistic-fabric-based component 20; that is, infiltration region/sublayer 21 includes strain-rate-sensitivity-hardening elastomer material 100 and ballistic-fabric-based material zoo.

(22) As distinguished from the exemplary inventive embodiments shown in FIGS. 1, 2, 5, and 6, the exemplary inventive embodiments shown in FIGS. 3, 4, 7, and 8 include a particle-filled strain-rate-sensitivity-hardening elastomeric (e.g., polyurea) matrix coating 30 that contains a plethora of microparticles 50, such as glass microspheres. The inventive embodiment of FIGS. 1 and 5 is analogous to the inventive embodiment of FIGS. 3 and 7 insofar as the elastomeric coating does not infiltrate into the ballistic-fabric-based component 20.

(23) The inventive embodiment of FIGS. 2 and 6 is analogous to the inventive embodiment of FIGS. 4 and 8 insofar as the elastomeric coating infiltrates into the ballistic-fabric-based component 20. Like infiltration region 21 (shown in FIGS. 2 and 6), infiltration region 23 (shown in FIGS. 4 and 8) is filled with plural (e.g., multiple) microspheres 50. Infiltration region 21 includes strain-rate-sensitivity-hardening elastomer material 100 and ballistic-fabric-based material zoo; in contrast, infiltration region 23 includes particle-filled strain-rate-sensitivity-hardening elastomeric matrix material 300 and ballistic-fabric-based material zoo.

(24) As shown in FIGS. 3 and 7, particle-filled elastomeric (e.g., polyurea) matrix coating layer 30 is bonded onto the top surface of ballistic-fabric-based component 20 “backing,” thereby establishing an interface 32 therebetween in a layered configuration of inventive armor. The particle-filled elastomeric matrix coating layer 30 is thin in comparison with the thickness of ballistic-fabric-based layer component 20. Interface 32 represents a demarcation between elastomeric coating layer 30 and ballistic-fabric-based component 20. FIGS. 3 and 7 thus illustrate an inventive embodiment in which there is a clear delineation (separation) between elastomeric coating layer 30 and ballistic-fabric-based component 20.

(25) FIGS. 4 and 8 illustrate an inventive embodiment characterized by a degree of infiltration (permeation) of the particle-filled elastomeric matrix coating 30 into the ballistic-fabric-based layer component 20. Particle-filled strain-rate-sensitivity-hardening elastomeric (e.g., polyurea) matrix coating 30 and ballistic-fabric-based layer component 20 overlap (intersect) to form an infiltration region 23, which represents both a sublayer of particle-filled strain-rate-sensitivity-hardening elastomeric matrix coating layer 30 and a sublayer of ballistic-fabric-based layer component 20.

(26) The ordinarily skilled artisan who reads the instant disclosure will appreciate that an elastomeric coating material 10/30 does not need to be directly infused into the underlying fabric material 20 in order to be infiltrative into fabric material 20. Rather, a relatively small quantity of elastomeric coating material 10/30 may infiltrate fabric material 20 when the elastomeric coating material 10/30 is exteriorly coupled (e.g., bonded) with fabric material 20.

(27) It may be considered that particle-filled strain-rate-sensitivity-hardening elastomeric matrix coating 30 includes two adjacent sublayers, viz., an elastomeric sublayer 33 and an infiltration sublayer 23. Similarly, it may be considered that ballistic-fabric-based layer component 20 includes two adjacent sublayers, viz., a fabric-based sublayer 22 and an infiltration sublayer 23. Infiltration region/sublayer 23 is a combination including elastomeric coating 30 and ballistic-fabric-based component 20; that is, infiltration region/sublayer 23 includes particle-filled strain-rate-sensitive elastomeric matrix material 300 strain-rate-sensitivity-hardening elastomer material 100 and ballistic-fabric-based material 200.

(28) FIGS. 1 through 4 each illustrate a laminar construction of the ballistic-fabric-based component 20, characterized by eleven plies 29. Ballistic-fabric-based material zoo is, for instance, a fiber-reinforced, resin-bound material. Many conventional helmets and other protective gear are fiber-reinforced polymer matrix composites (PMCs) containing a high volume fraction of fibers (e.g., fabrics). A conventional ballistic protective helmet is typically characterized by a low polymeric (e.g., resin) matrix content and a fibrous configuration, somewhat akin to that of an upside-down bird's nest, wherein the fibers act to “catch” a bullet. Ballistic PMCs commonly contain fibers of 80 or more percent by volume, and contain relatively little polymeric matrix material (e.g., resin binder), for instance on the order of 15 percent by volume.

(29) According to frequent inventive practice of infiltrative embodiments, the elastomeric coating 10/30 at least substantially infiltrates the first ply 29; that is, infiltration region 21 or 23 extends through approximately the entire width of the front-most ply 29. In exemplary inventive practice, a low amount of a resinous constituent in conjunction with a ballistic fibrous constituent in a ballistic-fabric-based material 200 may allow an elastomeric material 100 to penetrate, to a significant degree, into the underlying substrate, viz., the ballistic-fabric-based material zoo, thereby forming a more rigid top surface of the elastomeric coating. Ballistic-fabric-based material zoo is characterized by plies (layers) 29 and a minimal resin content of 14 to 20 percent, by way of example. The low resin content may permit infusion of elastomeric material 100 into at least the first ply 29 of a ballistic-fabric-based material zoo.

(30) With reference to FIGS. 9 through 16, according to exemplary practice of the present invention an elastomeric coating 10/30 forms an integral shell that resists penetration by sharp and pointed objects. Depending on the inventive embodiment, the elastomeric coating can be an unfilled elastomeric (e.g., polyurea) coating 10 (such as shown in FIGS. 1, 2, 5, and 6) or a particle-filled elastomeric (e.g., polyurea) matrix coating 30 (such as shown in FIGS. 3, 4, 7, and 8). FIGS. 12 through 16 each illustrate an example of an impelled arrow 40 impacting an armor system. FIG. 12 shows an example of interaction of an arrow 40 with a conventional ballistic armor system. FIGS. 13 through 16 each show an example of interaction of an arrow 40 with an inventive ballistic armor system.

(31) As distinguished from an exemplary inventive ballistic armor system, a conventional ballistic armor system includes a ballistic fabric material 20 and does not include any strain-rate-sensitivity-hardening elastomeric material. As shown by way of example in FIG. 12, impelled arrow 40 moving in direction d transpierces a conventional ballistic fabric armor 20. Arrowhead 401, or a substantial portion thereof, penetrates completely through conventional fabric armor 20 and is manifestly injurious to the individual who is wearing the conventional fabric armor 20.

(32) Unlike a conventional ballistic fabric armor, an exemplary inventive armor is capable of resisting both bullets and arrows. FIGS. 13 and 15 each depict impingement of an arrow 40 upon an inventive armor embodiment having an unfilled strain-rate-sensitivity-hardening elastomer coating 10. FIGS. 14 and 16 each depict impingement of an arrow 40 upon an inventive armor embodiment having a particle-filled strain-rate-sensitivity-hardening elastomeric matrix material coating 30. In contrast to conventional ballistic fabric armor systems, an exemplary inventive armor system includes not only a ballistic fabric material 20 but also includes, associated therewith, a strain-rate-sensitivity-hardening elastomeric material 10 or 30.

(33) The present invention's ballistic fabric component 20 is capable of defeating ballistic threats. In addition, the present invention's elastomeric coating component 10, situated on a ballistic fabric 20, is capable of defeating pointed, sharp-cutting projectiles, such as the types of broadhead arrows that are portrayed by way of example in FIGS. 9 through n. The present invention's elastomeric coating is thick enough to impede a broadhead arrow, and yet is thin enough to promote wearability as well as noninterference with the ballistic-protective mechanism of the fabric-based component.

(34) An inventive armor system may resist sharp or pointed weaponry in any of various ways. FIGS. 13 through 16 exemplify possible dynamics of how an inventive armor may resist sharp or pointed weaponry. These examples portray “non-infiltrative” inventive embodiments, that is, inventive embodiments in which the elastomeric coating does not infiltrate to any extent into the fabric component. In the light of the instant disclosure, the ordinarily skilled artisan will appreciate that the inventive principles demonstrated in FIGS. 13 through 16 will similarly apply to “infiltrative” inventive embodiments, that is, inventive embodiments in which the elastomeric coating does to some extent infiltrate into the fabric component.

(35) As depicted by way of example in FIGS. 13 and 14, respectively, upon impact with an inventive armor, a broadhead arrow traveling in initial direction d may ricochet (e.g., rebound or bounce) off a strain-rate-sensitivity-hardening elastomeric material coating 10/30, thus travelling divergently away from the inventive armor in a ricochet direction r. As another example, an elastomeric coating 10/30 may resist penetration in a manner resulting in breakoff of a tip portion 41 of an arrowhead 401, such as depicted by way of example in FIGS. 15 and 16, respectively.

(36) As shown in FIGS. 15 and 16, tip portion 41 breaks off of arrowhead 401 while arrow 40 continues to traverse the inventive armor. Tip portion 41 remains immovably captured within the elastomeric coating 10/30 and/or the ballistic fabric 20, while the intact portion of arrow 40 continues to travel approximately in direction d. Only a small portion of arrowhead 401 pierces completely through the inventive armor, viz., transpierce portion 43, which inwardly projects from the inside surface of ballistic fabric 20 and has a front breakoff edge 44. Under many circumstances transpierce portion will protrude inwardly without significant personal injury, particularly if the wearer is also wearing padding or other material beneath the inventive armor.

(37) Accordingly, as diagrammatically illustrated in FIGS. 15 and 16, the hard surface afforded by the elastomeric coating 10/30 enables the underlying ballistic fabric material 20 to resist the degraded arrowhead or any follow-on bullets or blast fragments such as from a warfighter scenario. Arrow 40 may experience (i) reduced velocity and/or (ii) tip breakage, due to a strain-rate-sensitivity-hardening of the elastomeric coating that is associated with the impact. The broken piece(s) of the arrow tip become(s) lodged in the ballistic fabric-based component. The major portion of the arrow tip continues to travel through the ballistic fabric-based component at a reduced rate, but does not penetrate as far as it would have if the arrow tip were speedier and entirely intact. The blunted arrow tip that remains after impact with the elastomeric coating does not proceed as far through the ballistic fabric-based component, as compared with what would occur upon encounter of the same arrow, at the same speed, with the ballistic fabric-based component in the absence of the elastomeric coating.

(38) Also referring to FIGS. 17 and 18, inventive testing was conducted with respect to inventive armor embodiments that included a ballistic fabric-based component 20 up to 0.4 inch thick. The experimental results indicate that a very lightweight nominal elastomeric coating of approximately 1/16 through 0.1 in on Kevlar® parts can afford, to lightweight tactical armor such as found in body armor and different helmet types, a significant protective quality against sharp-edged point projectiles. FIG. 17 conveys that inventive practice admits of multifarious combinations of the respective thicknesses of the elastomeric coating thickness and the fabric-based component. As frequently practiced the present invention provides for a thickness ratio in the approximate range between 0.15 and 0.35.

(39) Inventive performance was investigated with respect to ballistic fabric-based components categorized in two discrete ranges of the pounds per square foot pressure unit (psf). The present inventors demonstrated the effectiveness of an embodiment of an inventive armor system that included a ballistic fabric-based component 20 construction on the order of 1.8 to 2.3 psf in combination with a polyurea coating 10 on the order of 0.08 to 0.10 inch thick. Further, the present inventors demonstrated the effectiveness of an embodiment of an inventive armor system that included a lighter ballistic fabric-based component 20 construction, viz., on the order of 1.3 to 1.7 psf, in combination with a polyurea matrix coating 30 on the order of 0.08 to 0.10 inch thick.

(40) The experiments that were undertaken by the present inventors involved two types of leftover panels from a Cooperative Research and Development Agreement (CRADA) program in which the U.S. Navy and DuPont Corporation collaborated to investigate helmet technology. The panel of the first type represented a light advanced Kevlar® helmet architecture (about 2.0 psf). The panel of the second type represented a very light Kevlar® construction (about 1.5 psf). It is noted that standard combat helmets currently used by the military have an areal density of about 2.2 psf. Razor-sharp broadhead arrows were used by the present inventors to test the efficacy of inventive practice, in particular the effects of inventive elastomeric coatings 10/30 in stopping penetration of the broadhead arrows. The arrows were launched at 25 yards with 55 lb of pull. The arrow used in the testing was a 100 grain broadhead with a 28¼ inch shaft.

(41) In the testing of the panel of the first type, half of the panel was coated with a thin, nominally 1/16 inch coating of polyurea. This polyurea coating was an unfilled strain-rate-sensitivity-hardening elastomer coating. As illustrated by way of example in FIG. 12, the penetration of the arrows into the uncoated half of the Kevlar® panel was sufficient to pierce into the skull of a human wearing a helmet corresponding to the uncoated half of the panel. In contrast, the arrows just bounced off the polyurea-coated half of the panel, such as illustrated by way of example in FIG. 13.

(42) In the testing of the panel of the second type, a particle-filled strain-rate-sensitivity-hardening elastomeric matrix coating was added to the panel to reach approximately a 2.0 psf level. The polyuria matrix coating on the second panel, exemplified in FIG. 16, was a polyurea filled with small glass microspheres constituting nominally 30 percent (weight percentage) of the overall weight of the elastomeric coating. The second panel's polyurea matrix coating 30 was produced by adding glass particulates 50 to a polyurea material constituent 10. The glass particulates 50 were each up to 100 microns in diameter and overall constituted up to 30 percent by weight of the polyurea matrix coating 30.

(43) As illustrated by way of example in FIG. 16, arrows were able to pierce through the particle-filled polyuria matrix coating and the very light Kevlar® material “backing.” However, the penetration level of each of the arrows was small, the projection distance less than the typical thickness of the pads between the helmet shell and human skull in typical use of a conventional combat helmet. The tip of the most deeply penetrating arrow was actually broken off while the arrow was passing through the elastomeric coating.

(44) The present invention, which is disclosed herein, is not to be limited by the embodiments described or illustrated herein, which are given by way of example and not of limitation. Other embodiments of the present invention will be apparent to those skilled in the art from a consideration of the instant disclosure, or from practice of the present invention. Various omissions, modifications, and changes to the principles disclosed herein may be made by one skilled in the art without departing from the true scope and spirit of the present invention, which is indicated by the following claims.