An impact-resistant antler-shaped bulletproof insert

Abstract

The present invention discloses an impact-resistant antler-shaped bulletproof insert, comprising a protective layer, a bulletproof layer and a buffer layer, wherein the bulletproof layer comprises a plurality of composite structural layers and a bonding layer distributed at intervals; the composite structural layer is composed of two materials of different hardness and softness, comprising a supporting rib plate and a composite structural unit, wherein the composite structural unit comprises a transition zone and a soft-hard combination zone, wherein the soft-hard combination zone comprises a plurality of soft sheets of different sizes and distributed in a linear gradient, a bridge groove connecting the soft sheets and a hard matrix. The bulletproof insert is conducive to improving the stress field distribution near the bullet impact point, effectively suppressing crack initiation and guiding crack deflection, avoiding the catastrophic failure mode in the traditional bulletproof insert, increasing strain energy and fracture energy, thereby greatly improving the bulletproof performance of the bulletproof insert.

Description

Technical Field

[0001] The invention belongs to the technical field of bulletproofing, and more specifically, relates to an impact-resistant imitation antler-shaped bulletproof inserting plate. Background Art

[0002] In the field of national defense and military industry, high-performance bulletproof vests can effectively improve the combat capability of individual soldiers. On the battlefield, in order to resist high-level bullet threats, bulletproof plates are often needed to be added to bulletproof vests. Existing bulletproof plates are composites of hard ceramics and fiberboards, with bulletproof fibers as the basis and bulletproof ceramics as the core component. When a bullet hits a bulletproof plate, the bullet first hits the top ceramic layer of the bulletproof plate, which shatters and absorbs most of the kinetic energy of the bullet. When the bullet hits the fiber layer, the fiber layer consumes the kinetic energy of the bullet by stretching, and wraps the bullet head and shrapnel, which plays a good protective role.

[0003] Commonly used bulletproof ceramic materials include aluminum oxide, silicon carbide and boron carbide, among which silicon carbide and boron carbide ceramics have excellent bulletproof performance with low density and high hardness. However, due to the low fracture toughness value of silicon carbide and boron carbide ceramics, they will show brittle failure when impacted by bullets, and the fragmentation range will cover the entire ceramic. Generally, the higher the hardness of the material, the higher its fragility. The stress concentration of ceramics near the bullet impact point is obvious, and cracks are easily generated and quickly spread to the surrounding area. In addition, in multiple bullet impacts, the cracked parts are usually unable to resist the bullet impact again. The existing bulletproof ceramic insert has a simple structure and is generally assembled from several small ceramic pieces. Although it can reduce the range of ceramic fragmentation when impacted by bullets to a certain extent, it destroys the strength of the entire ceramic plate and still cannot change the brittle failure mode of the ceramic. This catastrophic failure mode seriously restricts the improvement of the bulletproof performance of the ceramic insert.

[0004] Male deer collide with each other to fight for territory, and their antlers are used as weapons in the battle. In this process, the antlers can withstand high impact loads and large bending moments without breaking, indicating that the antlers have very good toughness and impact resistance. Figure 1 As shown, this is mainly due to the porous structure inside the antler. Along the radial direction, the porosity of the antler gradually increases from the inside to the outside, and the pore radius gradually decreases from the inside to the outside, thus providing higher strength and toughness. Summary of the invention

[0005] The purpose of the present invention is to provide an impact-resistant antler-shaped bulletproof plug plate, which overcomes the shortcomings of the existing bulletproof plug plate, such as obvious stress concentration, easy initiation and expansion of cracks, catastrophic failure mode and poor bulletproof performance when the bulletproof plug plate is impacted due to its simple structure.

[0006] To achieve the above object, the technical solution adopted by the present invention is: an impact-resistant antler-shaped bulletproof insert, comprising a protective layer, a bulletproof layer and a buffer layer distributed in sequence from the impact surface to the back surface, wherein the protective layer, the bulletproof layer and the buffer layer are connected by bonding;

[0007] The bulletproof layer comprises a plurality of composite structural layers, and a bonding layer is arranged between adjacent composite structural layers; the composite structural layer comprises supporting ribs distributed in a grid shape and a plurality of composite structural units; the composite structural units are located in the grid formed by the supporting ribs, and the composite structural units are connected to the supporting ribs by bonding;

[0008] On any cross section of the composite structure layer along the thickness direction, the corresponding positions of the supporting ribs and the composite structure units in all odd-numbered layers are the same, the corresponding positions of the supporting ribs and the composite structure units in all even-numbered layers are the same, and the positions of the supporting ribs and the composite structure units in adjacent composite structure layers are relatively staggered;

[0009] The composite structure unit includes a soft-hard combination area and a transition area; the soft-hard combination area includes a soft thin sheet, a hard matrix and a bridging groove, and a number of irregularly shaped soft thin sheets are embedded in the hard matrix, and the soft thin sheets are distributed in a network; the size of the soft thin sheets gradually decreases from the middle area to the surrounding area of ​​the composite structure unit 8, and the number gradually increases; the bridging groove is used to connect three adjacent soft thin sheets, and is distributed in a non-continuous V shape in the composite structure unit, and the bridging groove is filled with soft material.

[0010] Furthermore, the protective layer and the buffer layer are made of the same material, which is high-performance fiberboard.

[0011] Furthermore, the supporting ribs, transition zone and hard matrix are made of hard ceramics, the material of which is one of silicon carbide and boron carbide.

[0012] Furthermore, the adhesive layer, the soft sheet and the bridge groove are made of one of epoxy resin and phenolic resin.

[0013] Furthermore, the thickness of the protective layer is 0.8-1.2 mm, the thickness of the bulletproof layer is 10-11 mm, and the thickness of the buffer layer is 8-9 mm.

[0014] Furthermore, the bulletproof layer includes 10 composite structure layers and 9 bonding layers, the thickness of each composite structure layer is 1.0 mm, and the thickness of each bonding layer is 0.1 mm.

[0015] Furthermore, the size of the composite structure unit is 40 mm×40 mm, and the diameter of the soft-hard combination area is 38 mm.

[0016] Furthermore, the relative staggered lateral distance between the supporting ribs and the composite structural units in adjacent composite structural layers is 20 mm.

[0017] A method for generating a composite structural unit in an impact-resistant antler-shaped bulletproof insert comprises the following steps:

[0018] S1. Each grid formed by the supporting ribs is divided into a number of annular areas with the same center, and the arc spacing of the annular areas gradually decreases from the inside to the outside;

[0019] S2, each annular area is equally divided into a number of sector rings, and a seed point is arranged in each sector ring, wherein the position of the seed point is randomly selected in the sector ring, and the number of seed points in the annular area gradually increases from the inside to the outside;

[0020] S3. Establish Thiessen polygon: select the perpendicular bisector of any two adjacent points as an edge of the Thiessen polygon. The closed area surrounded by several perpendicular bisectors is the Thiessen polygon.

[0021] S4, reducing the Thiessen polygon and setting the reduced new polygon as a soft sheet: taking the centroid of the Thiessen polygon as the base point, reducing the Thiessen polygon at a certain ratio to form a new polygon; the new polygon is the setting area of ​​the soft sheet, and a plurality of soft sheets are embedded into the interior of the hard substrate;

[0022] S5, connecting three adjacent soft sheets and setting a V-shaped bridge groove 13: connecting the centers of corresponding sides of three adjacent soft sheets 11, and setting two V-shaped connecting lines as the bridge groove 13.

[0023] Furthermore, in step S1, the arc spacing of the circular area changes from the inside to the outside in a linear gradient; in step S2, the number of seed points in the circular area changes from the inside to the outside in a linear gradient; in step S4, the reduction factor of the Thiessen polygon is 0.4-0.45, and the volume fraction of the soft material in the composite structure layer is 10%-15%.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. This antler-like bulletproof insert is composed of two materials of different hardness and softness, which is beneficial to improve the stress field distribution near the bullet impact point, reduce the stress concentration, increase the contact area between the bullet and the bulletproof insert, avoid catastrophic damage mode of the overall structure, and greatly improve the bulletproof performance of the bulletproof insert.

[0026] 2. The supporting ribs in the bulletproof layer play a good supporting role, preventing the overall structural strength from being reduced due to the addition of soft materials in the composite structure layer.

[0027] 3. The bulletproof layer adopts multiple composite structural layers, and the adjacent composite structural layers are staggered at a certain distance, which improves the crack propagation mode, is conducive to guiding the deflection of cracks propagating along the thickness direction, effectively prolongs the crack propagation path, and improves the fracture energy.

[0028] 4. The bonding layer in the bulletproof layer creates a tendency for relative sliding between adjacent composite structural layers, so the bonding layer produces greater shear stress and shear strain, further promoting energy absorption.

[0029] 5. In the composite structural unit, multiple irregularly shaped soft sheets are embedded in the hard matrix. The closer to the outside, the smaller the size of the soft sheets and the greater the number of them, thereby changing the strength distribution within the composite structural unit, changing the direction of the bullet's travel, reducing the speed of the bullet along the thickness direction of the bulletproof insert, and improving the toughness of the composite structural unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is the microstructure of the antler in the background technology.

[0031] Figure 2 The overall structure diagram of the impact-resistant antler-shaped bulletproof insert is shown in FIG.

[0032] Figure 3 This is a side view of the bulletproof layer.

[0033] Figure 4 It is a schematic diagram of the transverse section of the supporting ribs in two adjacent composite structure layers.

[0034] Figure 5 Schematic diagram of composite structure layer.

[0035] Figure 6 Schematic diagram of the composite structure unit.

[0036] Figure 7 Schematic diagram for the generation of the soft-hard combination area.

[0037] In the figure: 1, protective layer 2, bulletproof layer 3, buffer layer 4, composite structure layer 5, bonding layer 6, supporting ribs 7, crack propagation path 8, composite structure unit 9, soft and hard combination area 10, transition area 11, soft thin sheet 12, hard matrix 13, bridging groove 14, seed point 15, Thiessen polygon. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Figures 2 to 7 This is an embodiment of the present invention, and the following is combined with the attached Figures 2 to 7 The present invention is further described.

[0040] like Figure 2 As shown, an impact-resistant antler-shaped bulletproof insert comprises a protective layer 1, a bulletproof layer 2 and a buffer layer 3 which are sequentially distributed from the impact surface to the back surface. The protective layer 1, the bulletproof layer 2 and the buffer layer 3 are connected by bonding, and the bonding agent is one of epoxy resin or phenolic resin.

[0041] The main component of the bulletproof layer 2 is hard ceramic, and the material is one of silicon carbide or boron carbide. Since silicon carbide and boron carbide ceramics have excellent anti-ballistic properties with low density and high hardness, they can greatly reduce the impact energy of bullets when used as bulletproof layers. The protective layer 1 and the buffer layer 3 are both high-performance fiberboards made of aramid fiber. Both the protective layer 1 and the buffer layer 3 are conducive to fixing the ceramic fragments in the bulletproof layer 2 in their original positions when impacted, preventing the ceramic fragments from flying out. The thickness of the buffer layer 3 is greater than that of the protective layer 1. Therefore, the buffer layer 3 can use its own flexible deformation to further absorb the impact energy of the bullet and wrap the warhead. In this embodiment, the lateral dimensions of the protective layer 1, the bulletproof layer 2 and the buffer layer 3 are 250mm×300mm.

[0042] like Figure 3-4As shown, the bulletproof layer 2 includes a plurality of composite structural layers 4, and a bonding layer 5 is provided between adjacent composite structural layers 4. Since the bonding layer 5 causes a tendency of relative sliding between adjacent composite structural layers 4, the bonding layer 5 generates a large shear stress and shear strain, thereby having a high strain energy and promoting energy absorption. The composite structural layer 4 includes a supporting rib 6 and a plurality of composite structural units 8 distributed in a grid shape, and the composite structural unit 8 is located in the grid formed by the supporting rib 6. The composite structural unit 8 is connected to the supporting rib 6 by bonding, and the bonding agent is one of epoxy resin or phenolic resin. The supporting rib 6 plays a good supporting role to prevent the overall structural strength from being reduced due to the addition of soft materials in the composite structural layer 4. On any cross section of the composite structure layer 4 along the thickness direction, the corresponding positions of the supporting ribs 6 and the composite structure units 8 in all odd-numbered layers are the same, the corresponding positions of the supporting ribs 6 and the composite structure units 8 in all even-numbered layers are the same, and the positions of the supporting ribs 6 and the composite structure units 8 in adjacent composite structure layers 4 are relatively staggered. This offset design is conducive to guiding the deflection of bullets and cracks, generating a tortuous crack propagation path 7, thereby effectively improving the fracture energy.

[0043] like Figure 5-6 As shown, the composite structure unit 8 includes a soft-hard combination area 9 and a transition area 10, and the soft-hard combination area 9 includes a soft sheet 11, a hard matrix 12 and a bridge groove 13. A plurality of irregularly shaped soft sheets 11 are embedded in the hard matrix 12, and the soft sheets 11 are distributed in a mesh. The size of the soft sheets 11 gradually decreases from the middle area to the surrounding area of ​​the composite structure unit 8, and the number gradually increases. This kind of irregularly shaped soft sheet 11, which gradually decreases in size from the inside to the outside and gradually increases in number from the inside to the outside, changes the strength distribution in the composite structure unit 8, changes the direction of the bullet's travel, reduces the speed of the bullet along the thickness direction of the bulletproof plug plate, and improves the toughness of the composite structure unit 8, improves the stress distribution in the contact area between the composite structure unit 8 and the bullet, reduces the stress concentration, increases the contact area between the bullet and the bulletproof plug plate, avoids the catastrophic failure mode of the overall structure, and enables the bulletproof plug plate to store more strain energy. The bridge groove 13 is used to connect three adjacent soft sheets 11, and is distributed in a discontinuous V-shape in the composite structural unit 8, and the bridge groove 13 is filled with soft material. This design allows cracks to pass through the hard matrix 12 and extend along the bridge groove 13 in the composite structural unit 8, thereby effectively improving the fracture energy.

[0044] The composite structure layer 4 is composed of two materials of different hardness and softness, wherein the supporting ribs 6, the transition zone 10 and the hard matrix 12 are all hard ceramics, and the material is one of silicon carbide or boron carbide. The bonding layer 5, the soft sheet 11 and the bridge groove 13 are made of viscoelastic material, and the material is one of epoxy resin or phenolic resin.

[0045] Furthermore, the thickness of the protective layer 1 is 0.8-1.2 mm, the thickness of the bulletproof layer 2 is 10-11 mm, and the thickness of the buffer layer 3 is 8-9 mm.

[0046] Furthermore, the bulletproof layer 2 includes 10 composite structure layers 4 and 9 adhesive layers 5, the thickness of each composite structure layer 4 is 1.0 mm, and the thickness of each adhesive layer 5 is 0.1 mm.

[0047] Furthermore, the size of the composite structure unit 8 is 40 mm×40 mm, the diameter of the soft-hard combination area 9 is 38 mm, and the lateral positions of the supporting ribs 6 and the composite structure units 8 in adjacent composite structure layers 4 are staggered by 20 mm, which is conducive to the deflection of the crack through the bonding layer 5 when the crack propagates along the thickness direction of the bulletproof insert, thereby effectively improving the fracture energy.

[0048] like Figure 7 As shown, the method for generating the composite structure unit 8 includes the following steps:

[0049] S1. Each grid formed by the supporting ribs 6 is divided into a plurality of annular areas. All the annular areas have the same center. From the inside to the outside, the arc spacing of the annular areas gradually decreases. The arc spacing of the annular areas changes linearly from the inside to the outside.

[0050] S2, each annular region is equally divided into a number of sector rings, and a seed point 14 is arranged in each sector ring. The positions of the seed points 14 are randomly selected in the sector ring, and the number of seed points 14 in the annular region gradually increases from the inside to the outside, and the number of seed points 14 in the annular region changes linearly from the inside to the outside;

[0051] S3, establishing Thiessen polygon 15: selecting the perpendicular bisector of any two adjacent seed points 14 as a side of Thiessen polygon 15, and the closed area surrounded by a plurality of perpendicular bisectors is Thiessen polygon 15;

[0052] S4, reducing the Thiessen polygon 15, and setting the reduced new polygon as the soft sheet 11: taking the centroid of the Thiessen polygon 15 as the base point, reducing the Thiessen polygon 15 at a certain ratio to form a new polygon; the new polygon is the setting area of ​​the soft sheet 11, and a plurality of soft sheets 11 are embedded in the interior of the hard matrix 12, the reduction multiple of the Thiessen polygon 15 is 0.4-0.45, and the volume fraction of the soft material in the composite structure layer 4 is 10%-15%;

[0053] S5. Connect three adjacent soft sheets 11 and set a V-shaped bridge groove 13: Connect the centers of corresponding sides of three adjacent soft sheets 11, and set two V-shaped connecting lines as the bridge groove 13.

Claims

1. An impact-resistant antler-shaped bulletproof insert plate, comprising a protective layer (1), a bulletproof layer (2) and a buffer layer (3) which are sequentially distributed from an impact surface to a back surface, wherein the protective layer (1), the bulletproof layer (2) and the buffer layer (3) are connected by gluing; The bulletproof layer (2) comprises a plurality of composite structural layers (4), wherein an adhesive layer (5) is provided between adjacent composite structural layers (4); the composite structural layer (4) comprises supporting ribs (6) and a plurality of composite structural units (8) distributed in a grid shape; the composite structural units (8) are located in the grid formed by the supporting ribs (6), and the composite structural units (8) and the supporting ribs (6) are connected by gluing; On any cross section of the composite structural layer (4) along the thickness direction, the corresponding positions of the supporting ribs (6) and the composite structural units (8) in all odd-numbered layers are the same, the corresponding positions of the supporting ribs (6) and the composite structural units (8) in all even-numbered layers are the same, and the positions of the supporting ribs (6) and the composite structural units (8) in adjacent composite structural layers (4) are relatively staggered; The composite structure unit (8) comprises a soft-hard combination area (9) and a transition area (10); the soft-hard combination area (9) comprises a soft sheet (11), a hard matrix (12) and a bridging groove (13); a plurality of irregularly shaped soft sheets (11) are embedded in the hard matrix (12), and the soft sheets (11) are distributed in a network; the size of the soft sheets (11) gradually decreases from the middle area to the surrounding area of ​​the composite structure unit (8), and the number gradually increases; the bridging groove (13) is used to connect three adjacent soft sheets (11), and is distributed in a non-continuous V-shape in the composite structure unit (8); the bridging groove (13) is filled with soft material.

2. The impact-resistant antler-shaped bulletproof plate according to claim 1, characterized in that: The protective layer (1) and the buffer layer (3) are made of the same material, which is high-performance fiberboard.

3. The impact-resistant antler-shaped bulletproof plate according to claim 1, characterized in that: The supporting ribs (6), the transition zone (10) and the hard matrix (12) are made of hard ceramics, the material of which is one of silicon carbide and boron carbide.

4. The impact-resistant antler-shaped bulletproof insert according to claim 1, characterized in that: The adhesive layer (5), the soft sheet (11) and the bridge groove (13) are made of one of epoxy resin and phenolic resin.

5. The impact-resistant antler-shaped bulletproof insert according to claim 1, characterized in that: The thickness of the protective layer (1) is 0.8-1.2 mm, the thickness of the bulletproof layer (2) is 10-11 mm, and the thickness of the buffer layer (3) is 8-9 mm.

6. The impact-resistant antler-shaped bulletproof plate according to claim 1, characterized in that: The bulletproof layer (2) comprises 10 composite structure layers (4) and 9 adhesive layers (5), the thickness of each composite structure layer (4) is 1.0 mm, and the thickness of each adhesive layer (5) is 0.1 mm.

7. The impact-resistant antler-shaped bulletproof insert according to claim 1, characterized in that: The size of the composite structure unit (8) is 40 mm×40 mm, and the diameter of the soft-hard combination area (9) is 38 mm.

8. The impact-resistant antler-shaped bulletproof plate according to claim 1, characterized in that: The relative offset lateral distance between the supporting ribs (6) and the composite structural units (8) in adjacent composite structural layers (4) is 20 mm.

9. A method for generating a composite structural unit in the impact-resistant antler-shaped bullet-proof insert according to claims 1 to 8, comprising the following steps: S1, each grid formed by the supporting ribs (6) is divided into a plurality of annular areas having the same center, and the arc spacing of the annular areas gradually decreases from the inside to the outside; S2, each annular region is equally divided into a number of sector rings, and a seed point (14) is arranged in each sector ring, wherein the position of the seed point (14) is randomly selected in the sector ring, and the number of the seed points (14) in the annular region gradually increases from the inside to the outside; S3, establishing Thiessen polygon (15): selecting the perpendicular bisector of any two adjacent seed points (14) as a side of Thiessen polygon (15), and the closed area surrounded by a number of perpendicular bisectors is Thiessen polygon (15); S4, reducing the Thiessen polygon (15) and setting the reduced new polygon as the soft sheet (11): taking the centroid of the Thiessen polygon (15) as the base point, reducing the Thiessen polygon (15) at a certain ratio to form a new polygon; the new polygon is the setting area of ​​the soft sheet (11), and a plurality of soft sheets (11) are embedded in the interior of the hard substrate (12); S5. Connect three adjacent soft sheets (11) and set a V-shaped bridge groove (13): connect the centers of corresponding sides of three adjacent soft sheets 11, and set two V-shaped connecting lines as the bridge groove (13).

10. The method for generating composite structural units in the impact-resistant antler-shaped bulletproof insert according to claim 9, characterized in that: In step S1, the arc spacing of the annular area changes from the inside to the outside in a linear gradient; in step S2, the number of seed points (14) in the annular area changes from the inside to the outside in a linear gradient; in step S4, the reduction factor of the Thiessen polygon (15) is 0.4-0.45, and the volume fraction of the soft material in the composite structure layer (4) is 10%-15%.

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