A biomimetic laminated ballistic-resistant ceramic material and a method for preparing the same

Abstract

The application discloses a kind of biomimetic laminated ballistic ceramic material, including matrix layer and embedded layer composition, it is matrix layer, embedded layer, matrix layer in turn by outside inside alternately stacked composition, wherein matrix layer is by B4C powder, SiC powder, nano additive, binder and plasticizer are made, embedded layer is Al2O3 powder, MgO or titanium boride at least one, hexagonal boron nitride powder, binder and plasticizer are made.The biomimetic laminated ballistic ceramic of the application has the advantages of light weight, high hardness, high toughness, good effect of anti-intensive attack, etc.Cutting after the ceramic sample is handled, and the target sample piece with the face density of about 27.5kg / m 2 The target sample piece is prepared by compounding with ultra-high molecular weight polyethylene fiber plate, 95 type 5.8mm ordinary bullet is carried out, and multiple bullet shooting can be effectively defended, and the highest can be continuously defended 8 bullet shooting, and the application is suitable for the protection demand of various light armored equipment and individual protection equipment to small caliber bullet, and the survival rate in battlefield is improved.

Description

Technical Field

[0001] This invention relates to the field of bulletproof materials technology, specifically to a biomimetic multilayered bulletproof ceramic material and its preparation method. Background Technology

[0002] In the field of armored equipment and individual soldier protection, the main function of ballistic ceramics is to grind sharp projectiles and dissipate their impact energy, reducing their penetration capability and effectively protecting armored equipment and critical organs of soldiers from damage, thus enhancing their battlefield survivability. Secondly, high hardness increases the material's plastic deformation work, thereby improving its ballistic resistance. Currently, in the field of armored equipment and individual soldier protection both domestically and internationally, traditional ceramic materials such as boron carbide and silicon carbide are mainly used. These materials have drawbacks such as high brittleness, low toughness, and poor resistance to concentrated attacks, which seriously affect combat effectiveness in harsh battlefield environments.

[0003] To improve the toughness of ballistic ceramic materials and enhance their resistance to repeated impacts, two major systems have been developed both domestically and internationally: multiphase ceramics and fiber-reinforced ceramic matrix composites. Multiphase ceramics introduce nano- to micron-sized particles at the grain boundaries of ceramic materials, utilizing the differences in their physical properties to create a stress state at the grain boundaries. This state attracts the deflection or bifurcation of the main crack, thereby improving toughness. However, this method has limited effectiveness in improving ceramic toughness, and its resistance to concentrated impacts cannot meet expectations. Fiber-reinforced ceramic matrix composites fundamentally solve the problem of low toughness in ceramics, but the nonlinear mechanical behavior generated by the weak interface between the fiber and the ceramic matrix results in a low proportional limit stress, which limits the use of fiber / ceramic matrices in high-stress protective materials. Furthermore, improving toughness often comes at the cost of sacrificing material hardness.

[0004] To withstand intense, high-stress attacks, composite anti-ceramics with high hardness, high toughness, and high energy absorption are needed to defend against multiple, continuous, and concentrated attacks. Summary of the Invention

[0005] The purpose of this invention is to provide a biomimetic laminated ballistic ceramic material with high hardness, high toughness, and excellent resistance to concentrated attacks, which can be applied to lightweight armored equipment and individual soldier protection. It solves the problems of low toughness and insufficient resistance to multiple attacks of ceramic materials such as boron carbide, silicon carbide, and multiphase toughened ceramics. At the same time, it effectively inhibits the decrease in material hardness and improves the hardness of the material to a certain extent, thus better ensuring the protective performance of armored equipment and individual soldier equipment.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] A biomimetic multilayered ballistic ceramic material is characterized by comprising a matrix layer and an embedded layer, wherein the matrix layer, the embedded layer, and the matrix layer are alternately stacked from the outside to the inside. The matrix layer is made of B4C powder, SiC powder, nano-additives, binder, and plasticizer. The embedded layer is made of Al2O3 powder, at least one of MgO or titanium boride, hexagonal boron nitride powder, binder, and plasticizer.

[0008] Furthermore, the thickness ratio of the substrate layer to the embedded layer is 3:1 to 8:1, preferably 5:1 to 8:1.

[0009] Furthermore, the matrix layer comprises, by mass percentage, 70-80 wt.% B4C powder, 10-20 wt.% SiC powder, 3-5 wt.% nano-additives, 3-7 wt.% binder, and 1-4 wt.% plasticizer.

[0010] Furthermore, the nano-additive is composed of at least one of silicon nitride, nano carbon black, and nano silicon powder, and diamond in a mass ratio of 1 to 2:1.

[0011] Furthermore, the embedded layer contains 85-90 wt.% hexagonal boron nitride powder, 6-8 wt.% of at least one of Al2O3 powder, MgO or titanium boride, 3-5 wt.% binder, and 1-3 wt.% plasticizer.

[0012] Furthermore, the adhesive is at least one of polyvinyl alcohol, polyvinyl butyral, isocyanate, and methylcellulose, and the plasticizer is at least one of glycerol, ethylene glycol, dibutyl phthalate, and butyl stearic acid.

[0013] A method for preparing a biomimetic multilayered ballistic ceramic material, characterized by: preparing a matrix layer component and an embedded layer component respectively; preparing the matrix layer component and the embedded layer component into a green blank; and sequentially subjecting the green blank to debinding and densification sintering. The matrix layer component is prepared by ball milling B4C powder, SiC powder, nano-additives, binder and plasticizer into a matrix layer slurry, and then casting it into a matrix layer component. The embedded layer component is prepared by ball milling Al2O3 powder, at least one of MgO or titanium boride, hexagonal boron nitride powder, binder and plasticizer into an embedded layer slurry, and then casting it into an embedded layer component.

[0014] Inspired by the shell structures of shellfish and crustaceans, which exhibit excellent impact resistance in nature, this invention utilizes biomimetic technology to prepare a layered biomimetic laminated ballistic ceramic material with a similar interface structure design. Its microstructure consists of alternating matrix and embedded layers, which extends the crack propagation path and improves the material's fracture toughness and energy absorption. However, during the laminated design of the matrix and embedded layers, it was found that the bonding between them is poor. During sintering and subsequent use, the matrix and embedded layers are prone to delamination, leading to a decrease in the overall performance stability of the ceramic material.

[0015] In this invention, diamond-containing nano-additives are introduced into the matrix layer (hard layer). These nano-additives, when pressed together with the embedded layers within the matrix layer, create a good pinning effect between the layers. During sintering, as densification increases, the interlayer bonding force is effectively enhanced. The introduction of diamond adjusts the difference in the coefficient of thermal expansion within the matrix layer, enhances the material's abrasive properties against projectiles, dissipates the impact kinetic energy of the projectile, and regulates crack deflection during impact. Furthermore, the introduction of diamond promotes increased densification during sintering.

[0016] Secondly, by introducing cubic boron nitride as the main component and alumina and other auxiliary components into the embedded layer (soft layer), and through interlayer...

[0017] It plays a role in synergistic toughening and reinforcement, making up for the shortcomings of traditional ceramic materials such as low toughness and poor resistance to multiple attacks.

[0018] Furthermore, the matrix slurry is made by mixing B4C powder, SiC powder and nano-additives and adding solvent, with a liquid-to-material ratio (vol.%) of 3:2 and a ball-to-material ratio of 2:1. The ball mill speed is 400~600 r / min, and the mixture is ball-milled and dispersed in a planetary ball mill for 8~12 h. Then, a binder is added and ball milling continues for 1~2 h, followed by the addition of a plasticizer and ball milling for another 1~2 h. The mixture is then degassed and partially solvent is removed by heating and vacuum treatment, and the viscosity of the matrix slurry is adjusted to 8~10 Pa·s.

[0019] During the preparation process, it was found that the diamond dispersion in the matrix layer was poor, resulting in significant agglomeration or deformation of the prepared matrix layer. This significantly affected the bonding performance between the matrix layer and the embedded layer. Through continuous experimentation, it was discovered that by selecting specific nano-additives to composite with diamond, using a specific binder, and adjusting the viscosity to the range of 8–10 Pa·s, the other nano-additives formed excellent encapsulation of diamond within this viscosity range, inhibiting diamond agglomeration and matrix material deformation, thus significantly improving the overall strength of the matrix layer.

[0020] Furthermore, the embedded layer slurry is prepared by adding at least one of Al2O3 powder, MgO or titanium boride, and hexagonal boron nitride powder to a solvent, with a liquid-to-solid ratio (vol. %) of 3:2 and a ball-to-solid ratio of 1:1. The ball mill is operated at a speed of 200-300 r / min and dispersed and mixed in a planetary ball mill for 6-8 hours. A binder is added and ball milling continues for 1-2 hours. A plasticizer is then added and ball milling continues for 1-2 hours. The mixture is then degassed and partially solvent is removed by heating and vacuum treatment. The viscosity of the resulting embedded layer slurry is 8-10 Pa·s.

[0021] Furthermore, the solvent used in the matrix layer slurry and the embedding layer slurry is at least one of deionized water, anhydrous ethanol, toluene, and trichloroacetic acid.

[0022] Furthermore, the casting temperature is 30~50℃, the casting speed is 500~800 pulses / s, and after casting, the material is dried and demolded to form a substrate layer component with a thickness of 150~300μm and an embedded layer component with a thickness of 30~60μm, respectively.

[0023] Furthermore, the debinding process involves heating the raw blank to 500-550°C in stages at a rate of 1-2°C / min under vacuum and inert gas protection, and holding it at that temperature for 4-5 hours to remove moisture, adhesives, toughening agents, and other organic matter from the raw blank.

[0024] Furthermore, the densification sintering involves heating to 1500±10℃ at a rate of 10~15℃ / min, holding at that temperature for 50~60min, then pressurizing to 40±2MPa, while simultaneously heating to 2100±10℃ at a rate of 10~15℃ / min, holding at that temperature and pressure for 240~300min, and then cooling to room temperature with the furnace after heating.

[0025] Most specifically, a method for preparing a biomimetic multilayered ballistic ceramic material is characterized by comprising the following steps:

[0026] (a) Formulation Design

[0027] Matrix material: 70-80 wt.% B4C powder, 10-20 wt.% SiC powder, 3-5 wt.% nano-additives, 3-7 wt.% binder, 1-4 wt.% plasticizer, wherein the nano-additives are at least one of silicon nitride, nano carbon black and nano silicon powder and diamond in a mass ratio of 1:1;

[0028] Embedded layer material: 85-90 wt.% hexagonal boron nitride powder, 6-8 wt.% of at least one of Al2O3 powder, MgO or titanium boride, 3-5 wt.% binder, and 1-3 wt.% plasticizer;

[0029] Solvent: at least one of deionized water, anhydrous ethanol, toluene, and trichloroacetic acid;

[0030] Binder: at least one of polyvinyl alcohol, polyvinyl butyral, isocyanate, and methylcellulose;

[0031] Plasticizer: at least one of glycerin, ethylene glycol, dibutyl phthalate, and butyl stearic acid;

[0032] (II) Preparation of components for each layer

[0033] (1) Preparation of matrix layer slurry: B4C powder, SiC powder and nano additives are mixed and solvent is added. The liquid-to-material ratio (vol.%) is 3:2 and the ball-to-material ratio is 2:1. The ball mill speed is 400~600 r / min. The mixture is placed in a planetary ball mill for ball milling and dispersion for 8~12 h. Then, polyvinyl butyral is added and ball milling is continued for 1~2 h. Then, dibutyl phthalate is added and ball milling is continued for 1~2 h. The mixture is degassed and some solvent is removed by heating and vacuum treatment. The viscosity of the matrix layer slurry is 8~10 Pa·s. It is ready for use.

[0034] (2) Preparation of the embedded layer slurry:

[0035] The powder of the intercalation layer material was added to a solvent at a liquid-to-solid ratio (vol. %) of 3:2 and a ball-to-solid ratio of 1:1. The ball mill was operated at a speed of 200-300 r / min and dispersed and mixed in a planetary ball mill for 6-8 hours. A binder was added and ball milling continued for 1-2 hours. A plasticizer was then added and ball milling continued for 1-2 hours. The mixture was then subjected to heating and vacuum treatment to degas and remove some of the solvent. The viscosity of the resulting intercalation layer slurry was 8-10 Pa·s. The slurry was then ready for use.

[0036] (3) The substrate layer slurry is cast using a high-precision ceramic casting film machine. The height of the casting doctor blade is set, the temperature is 30~50℃, and the casting speed is 500~800 pulses / s. After casting and drying, the substrate layer component with a thickness of 150~300μm is formed. The embedded layer slurry is cast using a high-precision ceramic casting film machine. The height of the casting doctor blade is set, the temperature is 30~50℃, and the casting speed is 500~800 pulses / s. After casting and drying, the embedded layer component with a thickness of 30~60μm is formed.

[0037] (III) Blank forming

[0038] The matrix layer components and embedded layer components are stacked and laid up sequentially in the order of matrix layer-embedded layer-matrix layer. The outermost layer after the layup is always the matrix layer. The thickness ratio of the matrix layer components to the embedded layer components is 3:1 to 8:1.

[0039] The layers are placed in a mold and held under pressure of 4-6 MPa at room temperature for 1-2 hours to form a green body;

[0040] (iv) Glue placement of the unfinished body

[0041] The green blank prepared in step (3) is placed in a vacuum sintering furnace and heated to 500-550°C at a rate of 1-2°C / min under vacuum and inert gas protection, and held for 4-5 hours.

[0042] (v) Densification sintering

[0043] Heat to 1500±10℃ at 10~15℃ / min, hold for 50~60min, then pressurize to 40±2MPa, and simultaneously heat to 2100±10℃ at 10~15℃ / min, hold for 240~300min. After heating, cool to room temperature with the furnace.

[0044] The present invention has the following technical effects:

[0045] This invention effectively solves the technical problems of poor uniformity of diamond dispersion in the matrix layer and low interlayer bonding strength in laminates. This results in biomimetic laminated ballistic ceramics based on energy dissipation mechanisms possessing advantages such as lightweight, high hardness, high toughness, and good resistance to concentrated impacts. The treated ceramic sample is cut and then composited with ultra-high molecular weight polyethylene fiberboard to prepare a composite with an areal density of approximately 27.5 kg / m³. 2 The target prototype was tested against the Type 95 5.8mm standard round. It can effectively defend against multiple rounds of fire, and can continuously defend against up to 8 rounds of fire. It is suitable for the protection needs of various types of lightweight armored equipment and individual protective equipment against small-caliber projectiles, and improves battlefield survivability. Attached Figure Description

[0046] Figure 1 : Schematic diagram of the biomimetic layered ballistic ceramic material structure in this invention.

[0047] Figure 2 The process curve for removing glue from the green body in this invention.

[0048] Figure 3 The densification sintering process curve used in this invention.

[0049] Figure 4 Example 3 of this invention: A biomimetic stacked ballistic ceramic target specimen prepared. Detailed Implementation

[0050] The present invention will be specifically described below through embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0051] Example 1

[0052] A method for preparing a biomimetic multilayered ballistic ceramic material, characterized in that:

[0053] (a) Formulation Design

[0054] Matrix material: 77 wt.% B4C powder, 10 wt.% SiC powder, 4 wt.% nano-additives, 7 wt.% binder, 2 wt.% plasticizer, wherein the nano-additives are composed of nano-silicon nitride powder and diamond in a mass ratio of 1:1;

[0055] Embedded layer material: 88 wt.% hexagonal boron nitride powder, 7 wt.% Al2O3 powder, 3 wt.% binder, 2 wt.% plasticizer;

[0056] Solvent: Anhydrous ethanol; Binder: Polyvinyl butyral; Plasticizer: Dibutyl phthalate;

[0057] (II) Preparation of components for each layer

[0058] (1) Preparation of matrix layer slurry: B4C powder, SiC powder and nano additives were mixed and solvent was added. The liquid-to-material ratio (vol.%) was 3:2 and the ball-to-material ratio was 2:1. The ball mill speed was 400 r / min. The mixture was placed in a planetary ball mill and dispersed for 12 h. Then, polyvinyl butyral was added and ball milling continued for 2 h. Dibutyl phthalate was added and ball milling continued for 2 h. The mixture was degassed and some solvent was removed by heating and vacuum treatment. The resulting matrix layer slurry had a viscosity of 9.7 Pa·s and was ready for use.

[0059] (2) Preparation of the embedded layer slurry:

[0060] The powder of the intercalation layer material was added to a solvent at a liquid-to-solid ratio (vol. %) of 3:2 and a ball-to-solid ratio of 1:1. The ball mill was set at a speed of 200 r / min and the mixture was dispersed and mixed in a planetary ball mill for 6 hours. Polyvinyl butyral was added and the mixture was ball-milled for another 2 hours. Then, dibutyl phthalate was added and the mixture was ball-milled for another 2 hours. The mixture was then degassed and partially dissolved by heating and vacuum treatment to prepare an intercalation layer slurry with a viscosity of 9.5 Pa•s for later use.

[0061] (3) The substrate layer slurry is cast using a high-precision ceramic casting film machine. The height of the casting doctor blade is set, the temperature is 30℃, and the casting speed is 500 pulses / s. After casting and drying, the substrate layer component is demolded to form a 180μm thick substrate layer component. The embedded layer slurry is cast using a high-precision ceramic casting film machine. The height of the casting doctor blade is set, the temperature is 30℃, and the casting speed is 500 pulses / s. After casting and drying, the embedded layer component is demolded to form a 60μm thick embedded layer component.

[0062] (III) Blank forming

[0063] The matrix layer components and embedded layer components are arranged according to Figure 1 The matrix layer-embedded layer-matrix layer shown is stacked sequentially, and the outermost layer after the stacking is always the matrix layer;

[0064] The layers are placed in a mold and held under pressure of 5 MPa for 1.5 hours at room temperature to form a green body;

[0065] (iv) Glue placement of the unfinished body

[0066] The green blank prepared in step (3) was placed in a vacuum sintering furnace and heated to 500°C at a rate of 2°C / min under vacuum and inert gas protection, and held for 5 hours.

[0067] (v) Densification sintering

[0068] The temperature is increased to 1500℃ at 10℃ / min and held for 60min. Then the pressure is increased to 40MPa, and the temperature is increased to 2100℃ at 10℃ / min and held for 300min. After heating, the furnace is cooled to room temperature.

[0069] Example 2

[0070] Unlike Example 1, the thickness of the embedded layer prepared was 45 μm, and the remaining steps were the same as in Example 1.

[0071] Example 3

[0072] Unlike Example 1, the thickness of the embedded layer prepared was 30 μm, and the remaining steps were the same as in Example 1.

[0073] The biomimetic multilayer ballistic ceramic material prepared in this invention was cut and polished, then composited with ultra-high molecular weight polyethylene fiberboard to form a target specimen. A standard 5.8mm continuous impact test (Type 95) was conducted, and the test results are as follows: Figure 4 As shown, the target specimen can withstand eight consecutive shots, and the back convexity after firing is less than 22mm, which fully meets the defense requirements.

[0074] Comparative Example 1

[0075] Unlike Example 1, the thickness of the embedded layer prepared was 20 μm, and the remaining steps were the same as in Example 1.

[0076] Comparative Example 2

[0077] Compared with Example 1, the difference is that the viscosity of the adjusted matrix slurry is 7.4 Pa·s, and the rest of the steps are the same as in Example 1.

[0078] Comparative Example 3

[0079] Compared with Example 1, the nano-silicon nitride in the nano-additive was replaced with an equal amount of diamond, and the remaining steps were the same as in Example 1.

[0080] Example 4

[0081] A method for preparing a biomimetic multilayered ballistic ceramic material, characterized in that:

[0082] (a) Formulation Design

[0083] Matrix material: 70 wt.% B4C powder, 20 wt.% SiC powder, 3 wt.% nano-additives, 3 wt.% binder, 4 wt.% plasticizer, wherein the nano-additives are composed of nano-silicon powder and diamond in a mass ratio of 1:1;

[0084] Embedded layer material: 90 wt.% hexagonal boron nitride powder, 6 wt.% titanium boride powder, 3 wt.% binder, 1 wt.% plasticizer;

[0085] Solvent: Deionized water; Binder: Polyvinyl alcohol; Plasticizer: Ethylene glycol;

[0086] (II) Preparation of components for each layer

[0087] (1) Preparation of matrix layer slurry: B4C powder, SiC powder and nano additives are mixed and solvent is added. The liquid-to-material ratio (vol.%) is 3:2 and the ball-to-material ratio is 2:1. The ball mill speed is 400~600 r / min. The mixture is placed in a planetary ball mill for ball milling and dispersion for 8 hours. Then, polyvinyl butyral is added and ball milling continues for 1 hour. Dibutyl phthalate is added and ball milling continues for 1 hour. The mixture is degassed and some solvent is removed by heating and vacuum treatment. The resulting matrix layer slurry has a viscosity of 8.2 Pa·s and is ready for use.

[0088] (2) Preparation of the embedded layer slurry:

[0089] The powder of the intercalation layer material was added to the solvent at a liquid-to-solid ratio (vol. %) of 3:2 and a ball-to-solid ratio of 1:1. The ball mill was set at a speed of 300 r / min and the mixture was dispersed and mixed in a planetary ball mill for 8 hours. Polyvinyl butyral was added and the mixture was ball-milled for another hour. Then, dibutyl phthalate was added and the mixture was ball-milled for another hour. The mixture was degassed and partially dissolved by heating and vacuum treatment to prepare an intercalation layer slurry with a viscosity of 9.2 Pa·s for later use.

[0090] (3) The substrate layer slurry is cast using a high-precision ceramic casting film machine. The height of the casting doctor blade is set, the temperature is 50℃, and the casting speed is 800 pulses / s. After casting and drying, the substrate layer component is demolded to form a 300μm thick substrate layer component. The embedded layer slurry is cast using a high-precision ceramic casting film machine. The height of the casting doctor blade is set, the temperature is 50℃, and the casting speed is 800 pulses / s. After casting and drying, the embedded layer component is demolded to form a 40μm thick embedded layer component.

[0091] (III) Blank forming

[0092] The matrix layer components and the embedded layer components are stacked and laid up sequentially in the order of matrix layer-embedded layer-matrix layer, and the outermost layer after the layup is the matrix layer;

[0093] The layers are placed in a mold and held under pressure of 4 MPa for 2 hours at room temperature to form a green body;

[0094] (iv) Glue placement of the unfinished body

[0095] The green blank prepared in step (3) was placed in a vacuum sintering furnace and heated to 550°C at a rate of 1°C / min under vacuum and inert gas protection, and held for 4 hours.

[0096] (v) Densification sintering

[0097] The temperature was increased to 1510℃ at a rate of 15℃ / min and held for 50 min. Then the pressure was increased to 42 MPa, and the temperature was increased to 2110℃ at a rate of 15℃ / min and held for 240 min. After heating, the furnace was cooled to room temperature.

[0098] Example 5

[0099] A method for preparing a biomimetic multilayered ballistic ceramic material, characterized in that:

[0100] (a) Formulation Design

[0101] Matrix material: 80 wt.% B4C powder, 11 wt.% SiC powder, 5 wt.% nano-additives, 3 wt.% binder, 1 wt.% plasticizer, wherein the nano-additives are composed of nano-silicon powder and diamond in a mass ratio of 1:1;

[0102] Embedded layer material: 85 wt.% hexagonal boron nitride powder, 7 wt.% Al2O3 powder, 5 wt.% binder, 3 wt.% plasticizer;

[0103] Solvent: at least one of deionized water, anhydrous ethanol, toluene, and trichloroacetic acid;

[0104] Binder: at least one of polyvinyl alcohol, polyvinyl butyral, isocyanate, and methylcellulose;

[0105] Plasticizer: at least one of glycerin, ethylene glycol, dibutyl phthalate, and butyl stearic acid;

[0106] (II) Preparation of components for each layer

[0107] (1) Preparation of matrix layer slurry: B4C powder, SiC powder and nano additives are mixed and solvent is added. The liquid-to-material ratio (vol.%) is 3:2 and the ball-to-material ratio is 2:1. The ball mill speed is 400~600 r / min. The mixture is placed in a planetary ball mill for ball milling and dispersion for 10 h. Then, polyvinyl butyral is added and ball milling is continued for 1.5 h. Then, dibutyl phthalate is added and ball milling is continued for 1.5 h. The mixture is degassed and some solvent is removed by heating and vacuum treatment. The resulting matrix layer slurry has a viscosity of 9.1 Pa·s and is ready for use.

[0108] (2) Preparation of the embedded layer slurry:

[0109] The powder of the intercalation layer material was added to a solvent at a liquid-to-solid ratio (vol. %) of 3:2 and a ball-to-solid ratio of 1:1. The ball mill was operated at a speed of 250 r / min and dispersed and mixed in a planetary ball mill for 7 h. Polyvinyl butyral was added and ball milling continued for 1.5 h. Then dibutyl phthalate was added and ball milling continued for 1.5 h. The mixture was degassed and partially dissolved by heating and vacuum treatment to prepare an intercalation layer slurry with a viscosity of 8.2 Pa·s for later use.

[0110] (3) The substrate layer slurry is cast using a high-precision ceramic casting film machine. The height of the casting doctor blade is set, the temperature is 40℃, and the casting speed is 600 pulses / s. After casting and drying, the substrate layer component is demolded to form a 250μm thick substrate layer component. The embedded layer slurry is cast using a high-precision ceramic casting film machine. The height of the casting doctor blade is set, the temperature is 40℃, and the casting speed is 600 pulses / s. After casting and drying, the embedded layer component is demolded to form a 50μm thick embedded layer component.

[0111] (III) Blank forming

[0112] The matrix layer components and the embedded layer components are stacked and laid up sequentially in the order of matrix layer-embedded layer-matrix layer, and the outermost layer after the layup is the matrix layer;

[0113] The layers are placed in a mold and held under pressure of 6 MPa for 1.5 hours at room temperature to form a green body;

[0114] (iv) Glue placement of the unfinished body

[0115] The green blank prepared in step (3) was placed in a vacuum sintering furnace and heated to 520°C at a rate of 1.5°C / min under vacuum and inert gas protection, and held for 4.5 h.

[0116] (v) Densification sintering

[0117] The temperature was increased to 1490℃ at 12℃ / min and held for 55 min. Then the pressure was increased to 38 MPa, and the temperature was increased to 2090℃ at 12℃ / min and held for 280 min. After heating, the furnace was cooled to room temperature.

[0118] After cutting and polishing the ballistic ceramic material samples prepared in each comparative example and each embodiment, they were combined with ultra-high molecular weight polyethylene fiberboard to form target specimens. The test was conducted using a 5.8mm ordinary continuous impact test with a Type 95 bullet, and the test results are shown in Table 1.

[0119] Table 1: Performance test data for each sample

[0120]

[0121] It can be seen that the biomimetic layered ballistic ceramic material prepared in this invention effectively solves the shortcomings of traditional ceramic materials, such as low toughness and insufficient resistance to concentrated impacts. The resulting material has the advantages of high hardness and high toughness, and can effectively defend against multiple projectiles. In the Type 95 5.8mm ordinary continuous projectile impact test, it can continuously defend against 8 projectiles.

Claims

1. A biomimetic layered ballistic ceramic material, characterized in that: The material comprises a matrix layer and an embedded layer, arranged alternately from the outside in. The matrix layer is made of B4C powder, SiC powder, nano-additives, binder, and plasticizer, and is composed of 70-80 wt.% B4C powder, 10-20 wt.% SiC powder, 3-5 wt.% nano-additives, 3-7 wt.% binder, and 1-4 wt.% plasticizer by mass percentage. The embedded layer is made of 85-90 wt.% hexagonal boron nitride powder, 6-8 wt.% of at least one of Al2O3 powder, MgO, or titanium boride, 3-5 wt.% binder, and 1-3 wt.% plasticizer. The nano-additives are composed of at least one of silicon nitride, nano-carbon black, and nano-silicon powder, mixed with diamond in a mass ratio of 1-2:

1. The thickness ratio of the matrix layer to the embedded layer is 3:1-8:

1.

2. The biomimetic laminated ballistic ceramic material as described in claim 1, characterized in that: The binder is at least one of polyvinyl alcohol, polyvinyl butyral, isocyanate, and methylcellulose, and the plasticizer is at least one of glycerol, ethylene glycol, dibutyl phthalate, and butyl stearic acid.

3. A method for preparing a biomimetic multilayered ballistic ceramic material as described in claim 2, characterized in that: The process includes preparing a matrix layer component and an embedded layer component, preparing the matrix layer component and the embedded layer component into a green blank, and sequentially subjecting the green blank to debinding and densification sintering. The matrix layer component is prepared by ball milling B4C powder, SiC powder, nano-additives, binder and plasticizer into a matrix layer slurry, and then casting it into a matrix layer component. The embedded layer component is prepared by ball milling Al2O3 powder, at least one of MgO or titanium boride, hexagonal boron nitride powder, binder and plasticizer into an embedded layer slurry, and then casting it into an embedded layer component.

4. The method for preparing a biomimetic multilayered ballistic ceramic material as described in claim 3, characterized in that: The matrix slurry is made by mixing B4C powder, SiC powder, and nano-additives with a solvent, with a liquid-to-material volume ratio of 3:2 and a ball-to-material ratio of 2:

1. The ball mill is operated at a speed of 400-600 r / min and is ball-milled and dispersed in a planetary ball mill for 8-12 hours. Then, a binder is added and ball milling continues for 1-2 hours. A plasticizer is then added and ball milling continues for 1-2 hours. The slurry is then degassed and partially dissolved by heating and vacuum treatment, and the viscosity of the matrix slurry is adjusted to 8-10 Pa·s.

5. A method for preparing a biomimetic multilayered ballistic ceramic material as described in claim 3 or 4, characterized in that: The embedded layer slurry is made by adding at least one of Al2O3 powder, MgO or titanium boride, and hexagonal boron nitride powder to a solvent, with a liquid-to-material volume ratio of 3:2 and a ball-to-material ratio of 1:

1. The ball mill is operated at a speed of 200-300 r / min and dispersed and mixed in a planetary ball mill for 6-8 hours. A binder is added and ball milling continues for 1-2 hours. A plasticizer is then added and ball milling continues for 1-2 hours. The slurry is then degassed and partially dissolved by heating and vacuum treatment, and the viscosity of the embedded layer slurry is adjusted to 8-10 Pa·s.

6. The method for preparing a biomimetic multilayered ballistic ceramic material as described in claim 5, characterized in that: The casting temperature is 30~50℃, the casting speed is 500~800 pulses / s, and after casting, the material is dried and demolded to form a matrix layer component with a thickness of 150~300μm and an embedded layer component with a thickness of 30~60μm.

7. The method for preparing a biomimetic multilayered ballistic ceramic material as described in claim 6, characterized in that: The debinding process involves heating the raw blank to 500-550°C in stages at a rate of 1-2°C / min under vacuum and inert gas protection, and holding it at that temperature for 4-5 hours.

8. The method for preparing a biomimetic multilayered ballistic ceramic material as described in claim 7, characterized in that: The densification sintering process involves heating the furnace at 10-15℃ / min to 1500±10℃, holding it at that temperature for 50-60 min, then pressurizing it to 40±2MPa, while simultaneously heating the furnace at 10-15℃ / min to 2100±10℃, holding it at that temperature and pressure for 240-300 min. After heating, the furnace is cooled to room temperature.

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