A ballistic-resistant ceramic and method of making the same
By preparing a composite coating group on the surface of a ceramic substrate that is exposed to projectiles, and utilizing the alternating structure of columnar crystal layers and lubricating layers, the problem of penetration of bulletproof armor under the impact of sharp projectiles was solved, and the projectile path deflection and frictional resistance were enhanced, thereby improving the bulletproof performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- AVIC ARMOR TECH CO LTD
- Filing Date
- 2023-10-30
- Publication Date
- 2026-07-10
AI Technical Summary
Existing bulletproof armor is easily penetrated by sharp projectiles at high speeds, making it difficult to effectively perform its ballistic protection function. Furthermore, sharp projectiles can easily create dents on the top of the ceramic convex structure, making it difficult to deflect the projectile's trajectory.
A composite coating group is fixed on the surface of a ceramic substrate facing the projectile. The coating group consists of three alternating columnar crystalline layers and two lubricating layers and is prepared by electron beam physical vapor deposition and physical vapor deposition methods to enhance the deflection of the projectile penetration path and frictional resistance.
It improves the penetration resistance of bulletproof armor, increases the energy consumption and contact area of projectile penetration, and enhances bulletproof performance.
Smart Images
Figure CN117553625B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of surface modification technology for bulletproof ceramics, and in particular relates to a bulletproof ceramic and its preparation method. Background Technology
[0002] Ballistic armor works by dissipating the energy of projectiles, slowing them down and rendering them harmless. Currently, most ballistic armor is made of ceramic composite armor, consisting of a ceramic faceplate and a composite material backplate. The high hardness of ceramic causes the projectile to deform, and during penetration, it breaks down and abrades the projectile, dulling it. The backplate then absorbs the remaining kinetic energy of the projectile through deformation, ultimately trapping it and achieving ballistic protection.
[0003] To meet the demands of modern battlefields, the ballistic protection performance of armor needs continuous improvement. Current solutions typically enhance the penetration resistance of ceramic composite armor by adjusting armor materials and composite structures. However, this armor is easily penetrated by high-speed impacts from sharp projectiles, making the design of armor materials and structures ineffective. Some researchers have modified the ceramic surface to a convex structure to alter the projectile's penetration path and thus improve ballistic protection. However, when a sharp projectile contacts the top area of the convex ceramic structure, the sharp point creates a dent in the ceramic, making it difficult to deflect the projectile's path. Summary of the Invention
[0004] Changing the penetration direction of a projectile increases its trajectory, thereby increasing the energy consumed during penetration and improving the armor's resistance to penetration. Furthermore, changing the projectile's penetration direction also increases the contact area between the target plate and the projectile, thus increasing the frictional resistance and improving the projectile's penetration resistance. This invention proposes a ballistic ceramic and its preparation method. Utilizing coating technology, through material and structural design on the surface of the ballistic ceramic, the projectile's path can be deflected, improving the overall ballistic protection effect of the ceramic.
[0005] A bulletproof ceramic is characterized in that a composite coating group is fixed on the projectile-facing surface of the ceramic substrate. The composite coating group includes at least three columnar crystalline layers, each prepared by electron beam physical vapor deposition (EB-PVD), stacked sequentially from bottom to top. A lubricating layer prepared by physical vapor deposition (PVD) is sandwiched between two adjacent columnar crystalline layers.
[0006] Furthermore, a transition layer is provided between the impact-facing surface of the ceramic substrate and the bottom columnar crystalline coating of the composite coating group to enhance the bonding strength between the ceramic substrate and the bottom columnar crystalline coating of the composite coating group.
[0007] Preferably, the transition layer is a Ti transition layer prepared by physical vapor deposition (PVD).
[0008] Furthermore, the columnar crystalline layer is an Al2O3 columnar crystalline layer prepared using an Al2O3 target via electron beam physical vapor deposition. The thickness of the columnar crystalline layer is 100–150 μm.
[0009] Alternatively, the columnar crystalline layer is a SiC columnar crystalline layer prepared using a SiC target via electron beam physical vapor deposition. The thickness of the columnar crystalline layer is 100–150 μm.
[0010] Furthermore, the lubricating layer is a MoS2 coating prepared using a MoS2 target via physical vapor deposition (PVD). The thickness of the lubricating layer is 20–50 μm.
[0011] Alternatively, the lubricating layer is a WS2 coating prepared using a WS2 target via physical vapor deposition (PVD). The thickness of the lubricating layer is 20–50 μm.
[0012] Furthermore, the ceramic matrix is B4C ceramic, Al2O3 ceramic, or SiC ceramic.
[0013] The preparation method for the bulletproof ceramic as described above includes:
[0014] Step 1: Clean the impact-facing surface of the ceramic substrate with alcohol;
[0015] Step 2: Prepare a transition layer on the impact-resistant surface of the ceramic substrate using physical vapor deposition (PVD);
[0016] Step 3: Prepare a composite coating group on the surface of the transition layer. The composite coating group includes at least three columnar crystal layers, which are prepared by electron beam physical vapor deposition (EB-PVD) respectively, stacked from bottom to top. A lubricating layer prepared by physical vapor deposition (PVD) is sandwiched between two adjacent columnar crystal layers.
[0017] The process parameters for EB-PVD are: deposition rate of 2-3 μm / min, substrate temperature to target melting point ratio of 0.3-0.5, vacuum degree of 6-8 Pa, and electron beam current intensity of 1-2 A.
[0018] The PVD process parameters are: vacuum degree of 5-10 Pa, voltage of 650-850 V, and current of 1-2 A.
[0019] The present invention features a composite coating group fixed on the projectile-facing surface of a ceramic substrate, with a columnar crystal layer as the surface layer. When a high-speed, sharp projectile penetrates the columnar crystal layer, the layer is crushed and destroyed. Due to the shape of each columnar crystal and the disordered arrangement of batches, the projectile experiences uneven force, resulting in an initial deflection of its penetration path. During continued penetration, the deflection of the projectile path generates lateral shear force, which activates the lubrication layer between adjacent columnar crystal layers, causing slippage and further deflecting the projectile's penetration path. Furthermore, the present invention includes at least three columnar crystal layers and two lubrication layers, providing at least two sets of sandwich-type slippage structures of "columnar crystal layer-lubrication layer-columnar crystal layer," ensuring multiple deflections of the projectile during penetration and thus guaranteeing the overall penetration resistance of the bulletproof ceramic. Attached Figure Description
[0020] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.
[0021] Figure 1 This is a cross-sectional schematic diagram of the composite layer structure of the present invention;
[0022] Figure 2 This is a schematic diagram of the microstructure of the single-layer columnar crystal layer of the present invention;
[0023] Figure 3 A comparison table of test results between the bulletproof ceramic used in this example and traditional bulletproof ceramic. Detailed Implementation
[0024] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.
[0025] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0026] As shown in the figure, a Ti transition layer is prepared on the surface of the ceramic substrate in this embodiment. A composite coating group is fixed on the Ti transition layer. This composite coating group includes three columnar crystal layers stacked from bottom to top, and a lubricating layer is sandwiched between two adjacent columnar crystal layers.
[0027] The preparation method for the above-mentioned bulletproof ceramic:
[0028] First, clean the surface of the B4C ceramic substrate with alcohol and then dry it with a hair dryer;
[0029] A Ti transition layer with a thickness of 50 μm was prepared on the projectile-facing surface of the treated B4C ceramic matrix using the PVD method.
[0030] Each SiC columnar crystal coating layer was prepared using the EB-PVD method, with a coating thickness of 150 μm. The process parameters were: vacuum degree of 7 Pa, deposition rate of 2.5 μm / min, substrate temperature to target melting point ratio of 0.4, and electron beam intensity of 2 A.
[0031] Each MoS2 lubricating layer was prepared by PVD, with a coating thickness of 30 μm. The process parameters were: vacuum degree of 6 Pa, voltage of 700 V, and current of 1.5 A.
[0032] See Figure 2 The schematic diagram of the microstructure of the columnar crystal layer shows that each columnar crystal in the columnar crystal layer extends roughly in the longitudinal direction, and the diameter of the column varies along its extension direction. The arrangement of each columnar crystal is also in a disordered and intricate form. These characteristics cause the projectile to be subjected to uneven force when penetrating the columnar crystal layer, resulting in an initial deflection of the penetration path. The deflection of the projectile path will generate a lateral shear force, which can activate the lubricating layer between the upper and lower adjacent columnar crystal layers, causing slippage, thereby further deflecting the projectile's penetration path.
[0033] Figure 3 The test results of the bulletproof ceramic in this embodiment are compared with those of traditional bulletproof ceramics, and it can be seen that the corresponding performance is greatly improved.
[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A bulletproof ceramic, characterized in that, A composite coating group is fixed on the projectile-facing surface of the ceramic substrate. The composite coating group includes at least three columnar crystal layers, which are prepared by electron beam physical vapor deposition (EB-PVD) respectively, stacked from bottom to top. A lubricating layer prepared by physical vapor deposition (PVD) is sandwiched between two adjacent columnar crystal layers. A transition layer is provided between the impact-facing surface of the ceramic substrate and the columnar crystalline coating at the bottom of the composite coating group. The transition layer is a Ti transition layer prepared by physical vapor deposition (PVD). The columnar crystal layer is an Al2O3 columnar crystal layer prepared by electron beam physical vapor deposition using an Al2O3 target, or a SiC columnar crystal layer prepared by electron beam physical vapor deposition using a SiC target. The lubricating layer is a MoS2 coating prepared by physical vapor deposition (PVD) using a MoS2 target, or a WS2 coating prepared by physical vapor deposition (PVD) using a WS2 target.
2. The bulletproof ceramic according to claim 1, characterized in that, The ceramic matrix is B4C ceramic, Al2O3 ceramic, or SiC ceramic.
3. A method for preparing bulletproof ceramic as described in claim 1 or 2, characterized in that, include: Step 1: Clean the impact-facing surface of the ceramic substrate with alcohol; Step 2: Prepare a transition layer on the impact-resistant surface of the ceramic substrate using physical vapor deposition (PVD); Step 3: Prepare a composite coating group on the surface of the transition layer. The composite coating group includes at least three columnar crystal layers, which are prepared by electron beam physical vapor deposition (EB-PVD) respectively, stacked from bottom to top. A lubricating layer prepared by physical vapor deposition (PVD) is sandwiched between two adjacent columnar crystal layers.
4. The method for preparing bulletproof ceramic according to claim 3, characterized in that, The thickness of the transition layer is 30~60μm; the thickness of the columnar crystal layer is 100~150μm; and the thickness of the lubricating layer is 20~50μm.