Body armor structure, method and performance

Abstract

Body armor structure including a unitary material body having strike and opposite faces, and an internal structure disposed between these faces which progresses from shatter-prone to ductile. The methodology of the invention includes the steps of responding to a projectile impact first with a fragmentation energy-dissipating mechanism, and thereafter augmenting such responding with a ductile elastic yield mechanism. The methodology further includes the step of telegraphing the responding action through a brittle/ductile transition region in the structure of the invention to engage the ductile elastic yield mechanism.

Description

BACKGROUND AND SUMMARY OF THE INVENTION

This invention relates to body armor structure, to methodology associated with this structure, and to performance characteristics of the structure. According to the invention, armor is formed utilizing thin-plate-like elements each having (a) a projectile strike face which, along with the integrated structure immediately adjacent it, is a hardened ceramic material, (b) an opposite face which, along with the integrated structure immediately adjacent it, is ductile in character, and (c) intermediate these ceramic and ductile materials, a continuous, brittle/ductile interface, or transition, zone. Thus, and especially to be noted about the structure of the invention, the opposite faces of the invention plate-like elements are dramatically different in character, and include (a) hardened, brittle ceramic, (b) ductile, and (c) brittle/ductile transition, regions. For purposes of illustration herein, the armor elements of this invention are presented as being tile-like in form. Though this is a preferable form of the invention, it is not a necessary form.

Preferably, the basic substance forming the armor structure just briefly outlined is titanium. With respect to the “elements” proposed by the invention, these can be thought of as taking the form of tiles which may have various different perimeter outlines, such as square, circular, hexagonal, and many others, etc. Dimensions associated with this perimeter can be varied to suit different applications, but typical might be that a square-perimeter tile has a side length of about 3-inches, with the same being the case for the diameter of a circular-perimeter tile.

Thickness can be different, and can be varied within the structure of a particular tile to suit different applications. So also choosable and selectively variable are the depth/thickness configurations of the mentioned brittle, transitional, and ductile regions within a tile.

A very suitable base material for the armor structure of this invention is an initally ductile titanium product called Tiadyne™ 3510 manufactured by ATI Wah Chang which is based in Albany, Oreg.

DESCRIPTION OF THE DRAWINGS

Generally speaking, FIGS. 1-8, inclusive, illustrate various forms, and in FIG. 2, their armor-performance behaviors, of body armor tiles made in accordance with this invention.

FIGS. 9 and 10 generally show use of armor tiles collectively to form a protective armor fabric.

FIGS. 11 and 12, respectively, show a method for forming the tile structures of FIGS. 1-8, inclusive, and the operating response behaviors of these formed structures.

In particular, FIG. 1 provides a simplified, isometric view of a thin, square-perimeter, armor tile made in accordance with the present invention.

FIG. 2 is a side elevation of one side of the tile of FIG. 1 generally illustrating the armoring response of this tile to a projectile impact on its strike face.

FIGS. 3-8, inclusive, illustrate cross-sectional profiles of modified forms of the tile of FIG. 1. Cross-sectional hatch lines are omitted from these figures for clarity purposes.

FIG. 9 shows, fragmentarily, a fabric made of armor tiles like the tile shown in FIGS. 1 and 2.

FIG. 10 shown, fragmentarily, another fabric made of armor tiles made in accordance with the invention, with these tiles each having a hexagonal perimetral configuration.

FIG. 11 is a block/schematic diagram of a preferred method for building the tile structure of this invention.

FIG. 12 is a block/schematic diagram illustrating the armoring performance of the structure of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Turning now to the drawings, FIG. 9 shows a basic square (or rectangular) cross section, armor tile, or body armor structure, 10. This tile, which is also referred to herein as a tile-configured element, as a unitary material body, and as a unitary armor structure, has a projectile strike face 10a, an opposite side, or differentiated-character opposite face, 10b (see FIG. 2 especially), and intermediate these faces, a hardened, brittle shatter-prone ceramic-layer region 10c a ductile layer region 10d, and a bridging brittle/ductile interface, or transition, or shatter-prone, layer region 10e. The overall thickness of tile 10 is about ⅜- to about ½-inches. Brittle ceramic region 10c has a thickness herein of about ⅓ of the total tile thickness. Transition region 10e has a thickness also of about ⅓ of this total thickness, and ductile region 10d has a thickness of about ⅓ of the same total thickness. The side dimension of tile 10 is about 1- to about 2-inches. It should be appreciated that these dimensions are matters of user/designer choice.

A double-headed arrow 12 illustrates the recognition that transition region 10e can have different, basic, overall positional dispositions (placements) within the thickness of tile 10 relative to opposite faces 10a, 10b. Two double-headed arrows 14, 16 illustrate the further recognition that one side or the other, or both, of region 10e can be positioned variously (by user choice) within the thickness of tile 10. The internal interfaces between these three layer regions, which regions collectively form what is referred to herein as a unitary material body, are continuous, in the sense that there is no sharp material discontinuity between next-adjacent regions. The internal structure of tile 10 is thus seen to progress from shatter-prone (face 10a, region 10c) to ductile (face 10b, region 10d).

Beginning with the above-mentioned ductile titanium material as a precursor material, tiles of this material having the thickness and perimetral outline decided upon by the user/designer are initially formed in any suitable, conventional manner.

Following this formation, one face only of a thus pre-formed tile structure is unconventionally (from one aide only) processed, as by heating in a controlled, oxidizing environment, to form in each tile the desired depth/configuration brittle ceramic region (herein titanium oxide) which is purposely developed, as just suggested above, on one side, and from one face, only, of the precursor tile. This is an important practice of the present invention, which practice yields a unique armor tile structure, wherein one side is a hardened, brittle ceramic material, the opposite side remains as a ductile material, and there is a continuous, brittle/ductile, interfacial transition region between these two other, very different regions. As will be seen, this formation practice, and the end-result structure which it produces, avoids the presence of any material characteristic other than ductility to exist on that side of a tile which is opposite its brittle ceramic side. Conventional, allover surface oxidizing would not accomplish this important end result.

FIG. 11 in the drawings provides a schematic, block-diagram illustration of this processing approach of the invention.

The armoring behavior which results from this processing approach will now be described.

FIG. 2 pictures schematically the response behavior of tile 10 when its strike face is hit by a projectile, such as a bullet, traveling toward the tile as indicated by an arrow 18 in FIGS. 1 and 2. FIG. 12 offers a block-diagram outline of the invention's impact response behavior. As a first response action, the brittle ceramic region 10c in the tile fragments to dissipate bullet energy quickly, utilizing a mechanism referred to herein as a fragmentation energy-dissipating mechanism. Additionally, and as will be discussed more fully later herein, the chosen configuration of strike face 10a may initially function to change the course of bullet (and/or bullet fragments) travel.

Fragmentation of region 10c is telegraphed through the brittle/ductile transition region 10e to ductile region 10d which deflects and deforms, yieldingly and elastically, further to dissipate bullet energy. This action is referred to herein as one utilizing a ductile elastic yield mechanism. The elastic yield response of region 10d is not hampered in any way by the presence of any other internal region “beyond” it as defined by tile face 10b. In other words, no material back-up is required to be placed adjacent tile face 10b.

By using different opposing facial characteristics in the tile structure of this invention, it is possible to employ the armoring qualities of the structure of the invention to design the specific manner in which a projectile's attack may be foiled. These possibilities include shaping the manner in which impact energy is addressed, and deflecting a projectile's post-initial-impact trajectory significantly. FIG. 3-8, inclusive, provide several modified-surface-profile alternative configurations for a tile, or the like, made in accordance with the invention. Such alternative surface configurations may be employed, as was suggested earlier herein, to control post-impact projectile (and fragments thereof) trajectory(ies). In FIGS. 3-8, inclusive, dash-dot lines are employed to illustrate the internal juxtapositions of the above-discussed brittle, brittle/ductile transition, and ductile regions in each illustrated tile element structure.

FIG. 3 illustrates a tile 20 which has one concave side 20a (the strike face side) and one opposite planar side 20b, as shown. The central depth of this concave side, shown at A, might typically be about 1/16- to about ⅛-inches. This also is a matter of designer/user choice.

FIG. 4 illustrates a double-symmetrical-concave-side tile 22 with a strike face 22a, and an opposite face 22b.

FIG. 5 illustrates a planar-side/convex-side tile 24. The dome 14a which forms the convex strike-face side of this tile may have a crown height B relative to the thickness of the tile at its perimeter, of about 1/16- to about ⅛-inches. The opposite face of tile 24 is shown at 24b

FIG. 6 shows a convex-side (26a)/concave-side (26b) tile 26.

FIG. 7 pictures a double-convex-side tile 28. In this tile, side 26a is the strike face side, and side 26b the opposite side.

FIG. 8 illustrates a tapered-cross-section tile 30 with a strike face side 30a, and an opposite side 30b.

FIGS. 9 and 10, fragmentarily, illustrate portions of two, different body armor fabrics 32, 34, respectively. Fabric 32 is formed with square-perimetered tiles 32a which are suitably attached, edge-to-edge, to a backing material 32b which might typically be made of a suitable woven ballistic material made of aramid fibers, such as Kevlar®. Fabric 34 is formed with hexagonal-perimetered tiles 34a which are similarly suitably attached to a backing material 34b which may be the same as material 32b.

These fabrics are merely suggestive of the many ways in which the structure of the present invention may easily and conveniently be deployed to form large body-armor expanses.

Thus, a novel body armor element structure (preferably, though not necessarily, in a tile form), methodology, and performance have been illustrated and described. A key feature in the structure of the invention is that armor elements made according to it are characterized by a unique through-element transitioning characteristic, including a hardened ceramic strike side, a ductile opposite side, and a brittle/ductile transition zone bridging these two sides.

The methodology of the invention features the steps of responding to a projectile impact first with a fragmentation energy-dissipating mechanism, and thereafter augmenting such responding with a ductile elastic yield mechanism. This methodology further includes the step of telegraphing the responding action through a brittle/ductile transition region in the structure of the invention to engage the ductile elastic yield mechanism.

Those skilled in the art may well determine that variations and modifications of the invention beyond those specifically presented herein may be made fully within the scope of the invention, and the claims herein are intended to encompass all such variations and modifications.

Claims

1-9. (canceled)

10. A method of forming an anti-projectile armoring element consisting entirely of a single oxidizable ductile metal and an oxide of that metal, and having opposite faces comprising

providing a precursor element consisting of an oxidizable, ductile metal and possessing both (a) such opposite faces, and (b) a defined thickness profile between such faces, such element having a capability for processing to create, within the element, and adjacent one only of its opposite faces which is to become a projectile strike face, an oxidized, brittle ceramic region formed of an oxide of the mentioned metal which, progressing through the element's thickness profile to its opposite face, transitions continuously through a brittle/ductile transition region to a non-oxidized, metal, ductile region which is adjacent the opposite face, and

so processing the element.

11-12. (canceled)

13. A method of forming an anti-projectile armoring element consisting entirely of titanium and an oxide of titanium, and having opposite faces comprising

providing a ductile-quality precursor element consisting of titanium and possessing both (a) such faces, and (b) a defined thickness profile between such faces, such element having a capability for processing to create, within the element, and adjacent only one of its faces which is to become a projectile strike face, an oxidized, brittle ceramic region formed of an oxide of titanium which, progressing through the element's thickness profile to its opposite face, transitions continuously through a brittle/ductile transition region to a non-oxidized, metal, ductile region which is adjacent the opposite face, and

so processing the element.

14. A method of forming an anti-projectile armoring component having opposite faces comprising

providing a ductile-quality, precursor component formed oxidizable elemental metal, and possessing both (a) such faces, and (b) a defined thickness profile between such faces, the metal in such component having a capability for processing to create, within the component, and adjacent one only of its faces which is to become a projectile strike face, an oxidized, brittle ceramic region formed of an oxide of the metal which, progressing through the component's thickness profile to its opposite face, transitions continuously through a brittle/ductile transition region to a non-oxidized, metal, ductile region which is adjacent the opposite face, and

so processing the component whereby, following processing, it consists solely of the elemental metal and its formed oxide.