Boron carbide composite ceramic material as well as preparation method and application thereof

Abstract

The invention relates to a boron carbide composite ceramic material and a preparation method and application thereof, and the preparation method comprises the following steps: carrying out ball milling on boron oxide powder, carbon powder, deionized water, a dispersant, a binder and an oxide sintering aid, and uniformly mixing to obtain slurry; drying, crushing and sieving the slurry to obtain mixed powder; paving the mixed powder on a carbon fiber plate, putting the carbon fiber plate into a graphite mold, and carrying out electric field assisted pressure sintering to obtain a sintered body composite material; bonding the carbon fiber surface of the sintered body composite material with a fiberboard to obtain a boron carbide composite ceramic material; wherein the electric field assisted pressure sintering process is as follows: the temperature is raised to 1600-1800 DEG C, and the pressure at the temperature raising stage is 40-120 MPa; the temperature is kept for 60-120 minutes, and the pressure at the temperature keeping stage is 90-110 MPa; cooling to 200-350 DEG C, wherein the pressure at the cooling stage is 40-60 MPa; and cooling to room temperature along with the furnace.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite materials, in particular to a boron carbide composite ceramic material and a preparation method and application thereof. BACKGROUND

[0002] With the progress of cutting-edge technology, high-energy, high-velocity weapons are constantly updated and iterated, and armored protective materials are facing the challenges of high-speed bullet resistance, multi-bullet resistance, rapid assembly, etc. At present, the types of armored protective materials in service are divided into metal bulletproof materials, ceramic bulletproof materials and high-performance fiber bulletproof materials, etc. Among them, the ceramic bulletproof material represented by boron carbide ceramic has become a hot spot in the field of bulletproof materials due to its high strength, high hardness, high elastic modulus, good stability, light weight and other characteristics.

[0003] Although the ceramic material has sufficient hardness, it is brittle and has low fracture strength, so it cannot be used as a homogeneous armor alone and must be supported by a rigid backboard; the fiber material has high modulus, high toughness, high compressive strength and high tensile strength, and can resist penetration and damage, and is often used as a backboard layer, and the two are often combined together by using adhesive or mechanical connection to form a ceramic composite material, which can take advantage of both materials and exhibit excellent bulletproof performance. However, this bonding method usually has the disadvantages of low bonding strength, poor toughness, and delayed stress wave transmission, etc. When impacted by high-speed bullets, the ceramic will break brittlely, causing the fiber backboard to be pierced, which seriously affects the combat effectiveness of the armored protective material.

[0004] Therefore, it is of great significance to better combine ceramic materials with fiber backboards to achieve better bulletproof performance. SUMMARY

[0005] The main purpose of the present application is to provide a boron carbide composite ceramic material and a preparation method and application thereof, and to solve the technical problem of how to better combine ceramic materials with fiber backboards to achieve better bulletproof performance, thereby being more suitable for practical use.

[0006] The purpose of the present application and the solution to its technical problems are realized by adopting the following technical scheme. According to the present application, a preparation method of a boron carbide composite ceramic material is provided, which comprises the following steps:

[0007] Mixing boron oxide powder, carbon powder, deionized water, dispersant, binder and oxide sintering aid by ball milling to obtain a slurry;

[0008] Drying, crushing and sieving the aforementioned slurry to obtain a mixed powder;

[0009] The mixed powder is laid on a carbon fiber plate and put into a graphite mold to obtain a sintered body composite material through electric field assisted pressure sintering;

[0010] The carbon fiber surface of the sintered body composite material is bonded with the fiber plate to obtain a boron carbide composite ceramic material.

[0011] The process of the electric field assisted pressure sintering is as follows:

[0012] The temperature is raised to 1600-1800℃, and the pressure in the temperature raising stage is 40-120MPa.

[0013] The temperature is kept for 60-120min, and the pressure in the temperature keeping stage is 90-110MPa.

[0014] The temperature is lowered to 200-350℃, and the pressure in the temperature lowering stage is 40-60MPa.

[0015] The temperature is lowered to 200-350℃, and the pressure in the temperature lowering stage is 40-60MPa.

[0016] The object and the technical problem of the present application can be further realized through the following technical measures.

[0017] Preferably, the preparation method of the boron carbide composite ceramic material, wherein the temperature raising rate is 80-150℃ / min, and the temperature lowering rate is 80-100℃ / min.

[0018] Preferably, the preparation method of the boron carbide composite ceramic material, wherein the particle size of the mixed powder is less than 300 mesh; and / or,

[0019] The dispersant is at least one of tetramethylammonium hydroxide, tristearin, sodium hexametaphosphate, polyacrylamide, polyvinylpyrrolidone, sodium dodecyl sulfate, sodium hydroxymethyl cellulose, phosphate ester and polyethylene glycol; and / or,

[0020] The binder is at least one of polyvinyl alcohol, polyvinyl butyral, methacrylate, cellulose, polyurethane, polyisobutylene and water-soluble phenol formaldehyde resin; and / or,

[0021] The sintering aid is at least one of Al2O3, Y2O3, TiO2 and ZrO2.

[0022] Preferably, the preparation method of the boron carbide composite ceramic material, wherein the mass ratio of the boron oxide powder to the carbon powder is (2-3):1.

[0023] Preferably, the preparation method of the boron carbide composite ceramic material, with the sum of the mass of the boron oxide powder and the mass of the carbon powder being 1, the mass of the deionized water being 1-5, the mass of the dispersant being 0.001-0.1, the mass of the binder being 0.01-0.05, and the mass of the sintering aid being 0-0.1.

[0024] Preferably, the preparation method of the boron carbide composite ceramic material, the specific method of the ball milling and mixing is that the ball milling and mixing is performed by using a horizontal ball mill, the rotating speed is 50-200 rpm, the time length is 0.5 h-10 h, and the ball-to-material ratio is (10-1):1.

[0025] Preferably, the preparation method of the boron carbide composite ceramic material, the type of the carbon fiber plate is at least one of polyacrylonitrile-based carbon fiber, viscose-based carbon fiber, pitch-based carbon fiber, lignin-based carbon fiber, and grown carbon fiber; and the thickness of the carbon fiber plate is 1-10 mm.

[0026] The type of the fiber plate is ultra-high molecular weight polyethylene fiber, aramid fiber, Kevlar fiber, or glass fiber; and the thickness of the fiber plate is 6-7 mm.

[0027] Preferably, the preparation method of the boron carbide composite ceramic material, an adhesive is used to bond the carbon fiber surface of the sintered body composite material and the fiber plate, so as to obtain the boron carbide composite ceramic material.

[0028] The type of the adhesive is epoxy resin adhesive, epoxy vinyl resin adhesive, polyurethane adhesive, or acrylic adhesive; and the bonding thickness is 0.2-1 mm.

[0029] The object and the technical problem of the present application are also achieved by the following technical solution. The present application provides a boron carbide composite ceramic material prepared by any of the above methods.

[0030] The object and the technical problem of the present application are also achieved by the following technical solution. The present application provides an application of the above boron carbide composite ceramic material in the field of protection.

[0031] By means of the above technical solution, the boron carbide composite ceramic material, the preparation method and the application thereof have at least the following advantages:

[0032] (1) In the conventional armor protection material, the interface bonding force between the ceramic and the fiber backboard layer is weak, when impacted by high-speed fragments, the ceramic will be brittle fracture, making the fiber backboard be penetrated, which seriously affects the combat effectiveness of the armor protection material. The size of the interface bonding strength is the key to affect the performance of the composite material, and the bonding strength is too large to fully play the toughening effect of the fiber, and the bonding strength is too small to obtain sufficient strength. In view of the above shortcomings, the patent application is designed by formula and electric field assisted pressure sintering technology, in the process of sintering at a certain temperature and pressure, boron oxide powder and carbon powder react, boron carbide crystals with orientation are grown in the pores of carbon fiber, then oxide sintering aid is added to form glass phase, fill in the pores, and form a sintered body composite material with dense structure. The boron carbide / carbon fiber transition layer with strong bonding force is formed between the two, and the good interface bonding can effectively transfer the projectile ability to the carbon fiber, and the energy of the projectile is dissipated in the form of compression, shear and tension of the carbon fiber, so that the excellent anti-ballistic performance of the carbon fiber is fully played.

[0033] (2) Compared with spark plasma sintering (SPS), the advantages of electric field assisted pressure sintering are: through direct current heating and axial pressure, rapid densification sintering and high temperature synthesis are realized. No expensive and difficult to control pulse power is used, the price is low, and large size ceramic materials can be formed.

[0034] (3) Using electric field assisted pressure sintering, nano or submicron boron carbide fine grains are obtained at a faster heating rate and larger pressure, and a densified boron carbide ceramic is formed.

[0035] (4) Through the electric field assisted pressure sintering technology, the carbon powder and the boron oxide powder generate boron carbide crystals with orientation in the pores of the carbon fiber under the action of high temperature and high pressure, the excess boron oxide powder can also become a sintering aid of boron carbide ceramic, become a glass phase filled in the pores, and form a boron carbide ceramic / carbon fiber transition layer with strong bonding force between the two, sinter the boron carbide ceramic and the carbon fiber plate integrally, solve the problem of poor interface bonding between the ceramic and the carbon fiber. Good interface bonding can effectively transfer the projectile ability to the carbon fiber, and the energy of the projectile is dissipated in the form of compression, shear and tension of the carbon fiber, so that the excellent anti-ballistic performance of the carbon fiber is fully played.

[0036] (5) The structure of the boron carbide composite ceramic material is that the boron carbide ceramic is used as the panel, the boron carbide / carbon fiber transition layer + carbon fiber plate is used as the intermediate layer, and the fiber plate is used as the flexible backboard, the overall structure is changed from hard to soft, which can consume more impact energy.

[0037] The above description is only a summary of the technical solutions of the present application. In order to make the technical means of the present application clearer and to enable the present application to be implemented according to the content of the description, the preferred embodiments of the present application are described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0038] Fig. 1 is a structural schematic diagram of a boron carbide composite ceramic material in some embodiments of the present application;

[0039] Fig. 2 is a structural schematic diagram of a rapid hot-pressing sintering furnace in some embodiments of the present application;

[0040] Wherein, 1-boron carbide ceramic; 2-boron carbide / carbon fiber transition layer; 3-carbon fiber plate; 4-fiber plate. DETAILED DESCRIPTION

[0041] In order to further illustrate the technical means and effects taken by the present application to achieve the predetermined purposes, the specific embodiments, structures, characteristics and effects of a boron carbide composite ceramic material, a preparation method thereof and applications thereof according to the present application are described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "embodiments" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0042] The present application provides a preparation method of a boron carbide composite ceramic material, as shown in Figs. 1-2 The preparation method comprises the following steps:

[0043] Mixing boron oxide powder, carbon powder, deionized water, dispersant, binder and oxide sintering aid by ball milling to obtain a slurry;

[0044] Drying, crushing and sieving the aforementioned slurry to obtain a mixed powder;

[0045] Laying the aforementioned mixed powder on a carbon fiber plate 3, placing it in a graphite mold, and performing electric field assisted pressure sintering to obtain a sintered body composite material;

[0046] Bonding the carbon fiber surface of the aforementioned sintered body composite material to a fiber plate 4 to obtain a boron carbide composite ceramic material;

[0047] The aforementioned electric field assisted pressure sintering process is as follows:

[0048] Raising the temperature to 1600-1800°C, and the pressure during the temperature raising stage is 40-120 MPa;

[0049] Maintaining the temperature for 60-120 min, and the pressure during the temperature maintaining stage is 90-110 MPa;

[0050] Cooling to 200-350℃, the cooling stage pressure is 40MPa-60MPa;

[0051] Cooling to room temperature.

[0052] Specifically, since the reaction of boron oxide powder and carbon powder to generate boron carbide requires extremely high reaction temperature, but too high temperature will cause abnormal growth of crystal grains, therefore, the electric field assisted pressure sintering method is adopted to simultaneously heat and press, the synergy of pressure and electric field helps the contact and diffusion of powder particles, reduces the sintering temperature and shortens the sintering time, and promotes the generation of boron carbide ceramic 1. The greater the pressure, the lower the required temperature, and the better the densification effect. For example, as shown in Fig. 2 indicated, the process can be realized by using a rapid hot-pressing sintering furnace, using direct current to heat the sintering material, and applying pressure to the material by a graphite pressure head and a graphite punch, and the sintering process is carried out in a vacuum chamber.

[0053] The temperature rising stage: the direct current passes through the graphite mold and the powder itself, generating Joule heat, which significantly improves the heating rate, and the carbon powder and boron oxide powder can quickly reach the sintering temperature and react, avoiding abnormal growth of crystal grains under long-time high temperature. The application of 40MPa-120MPa pressure helps to promote particle rearrangement and break up agglomerates in the early stage of sintering. When the temperature rises to about 450℃, the boron oxide powder melts to form a glassy liquid, which helps to mix with the carbon powder. Moreover, at 1000℃-1800℃, the oxide sintering aid forms a liquid phase to promote the densification process.

[0054] In the holding stage, 90MPa-110MPa pressure is applied for 60min-120min to inhibit grain growth and obtain high-density, micro-nano-sized boron carbide crystals, and to orient the boron carbide crystals grown in the carbon fiber pores to form needle-like or rod-like structures.

[0055] In the cooling stage, the application of 40MPa-60MPa pressure can gradually shape the needle-like or rod-like boron carbide crystals in the carbon fiber pores, maintaining the orientation of the crystal structure. The two are connected together by the molten sintering aid, forming a boron carbide / carbon fiber transition layer 2 with strong bonding force, and sintering the boron carbide / carbon fiber integrally.

[0056] The patent application is through the formula design and electric field auxiliary pressure sintering technology, in the process of sintering at a certain temperature and pressure, boron oxide powder and carbon powder react, grow in the pores of carbon fiber with oriented needle or rod boron carbide crystal, then add oxide sintering aid to form glass phase, fill in the pores, form the sintered body composite material with dense structure. The transition layer 2 of boron carbide / carbon fiber with strong bonding force is formed between the two, the good interface bonding can effectively transfer the projectile ability to the carbon fiber, and the energy of the projectile is dissipated in the form of compression, shear and tension of the carbon fiber, so that the excellent anti-ballistic performance of the carbon fiber is fully utilized.

[0057] The boron carbide composite ceramic material provided by the application has the structure that the boron carbide ceramic 1 is used as a panel, the boron carbide / carbon fiber transition layer 2 and the carbon fiber plate 3 are used as an intermediate layer, and the fiber plate 4 is used as a flexible back plate, and the overall structure is changed from hard to soft, so that more impact energy can be consumed.

[0058] Preferably, the temperature rising rate is 80-150 DEG C / min, and the temperature falling rate is 80-100 DEG C / min. The temperature rising rate and the temperature falling rate in this stage are preferably selected, so that a good sintering neck is formed, the densification sintering is facilitated, the grain coarsening is prevented, the safe removal of the binder is facilitated, the risk of ceramic cracking and deformation is greatly reduced, and the production efficiency is improved.

[0059] Preferably, the particle size of the mixed powder is less than 300 mesh; and / or, the particle size of the mixed powder is conducive to the generation of high-density ceramics.

[0060] The dispersant is at least one of tetramethylammonium hydroxide, tristearin, sodium hexametaphosphate, polyacrylamide, polyvinylpyrrolidone, sodium dodecyl sulfate, sodium hydroxymethyl cellulose, phosphate and polyethylene glycol; and / or,

[0061] The binder is at least one of polyvinyl alcohol, polyvinyl butyral, methacrylate, cellulose, polyurethane, polyisobutylene and water-soluble phenolic resin; and / or,

[0062] The sintering aid is at least one of Al2O3, Y2O3, TiO2 and ZrO2.

[0063] Preferably, the mass ratio of the boron oxide powder to the carbon powder is (2-3):1. The mass ratio of the reactants boron oxide and carbon powder is about 1.66:1, and in the actual reaction process, the boron oxide is slightly excessive in order to make the carbon powder react completely. In the sintering process, the boron oxide will volatilize significantly above 1300 DEG C, causing boron loss, so that the excessive boron oxide can play a role as a reactant or a sintering aid.

[0064] Preferably, the mass of the aforementioned boron oxide powder and the aforementioned carbon powder is 1, the mass of the deionized water is 1-5, the mass of the aforementioned dispersant is 0.001-0.1, the mass of the aforementioned binder is 0.01-0.05, and the mass of the aforementioned sintering aid is 0-0.1.

[0065] Preferably, the specific method of the aforementioned ball milling mixing is as follows: a horizontal ball mill is used for ball milling mixing, the rotating speed is 50-200 rpm, the time length is 0.5 h-10 h, and the ball-to-material ratio is (10-1):1. If the rotating speed is too low or the time length is too short, the mixing is not uniform; if the rotating speed is too fast or the time length is too long, ball milling impurities are introduced into the slurry, affecting the purity of the slurry.

[0066] Preferably, the aforementioned carbon fiber plate 3 is at least one of polyacrylonitrile-based carbon fiber, viscose-based carbon fiber, pitch-based carbon fiber, lignin-based carbon fiber, and grown carbon fiber; and the thickness of the aforementioned carbon fiber plate 3 is 1-10 mm.

[0067] The aforementioned fiber plate 4 is ultra-high molecular weight polyethylene fiber, aramid fiber, Kevlar fiber, or glass fiber; and the thickness of the aforementioned fiber plate 4 is 6-7 mm.

[0068] Preferably, an adhesive is used to bond the carbon fiber surface of the sintered body composite material and the fiber plate 4, so as to obtain a boron carbide composite ceramic material.

[0069] The adhesive is epoxy resin adhesive, epoxy vinyl resin adhesive, polyurethane adhesive, or acrylic adhesive; and the bonding thickness is 0.2-1 mm.

[0070] The present application provides a boron carbide composite ceramic material prepared by any of the aforementioned methods.

[0071] The present application provides the use of the aforementioned boron carbide composite ceramic material in the field of protection.

[0072] The present application will be further described in conjunction with specific examples, but it should not be understood as limiting the scope of protection of the present application. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present application still belong to the scope of protection of the present application.

[0073] Unless otherwise specified, the materials and reagents involved below are commercially available goods well known to those skilled in the art; unless otherwise specified, the methods described are well-known methods in the art. Unless otherwise defined, the technical terms or scientific terms used should be the usual meaning understood by those skilled in the art in the field to which the present application belongs.

[0074] Example 1

[0075] The embodiment provides a boron carbide composite ceramic material and a preparation method and application thereof. Figs. 1-2

[0076] The boron oxide powder with a particle size of 0.5 μm and a purity of 99.9% is weighed at 100 g, the carbon powder is weighed at 50 g, the deionized water is weighed at 500 ml, the mixture of the dispersants cellulose and tristearin is weighed at 10 g, the binder polyvinyl butyral is weighed at 2 g, and the sintering aid Al2O3 is weighed at 0.25 g, the above materials are uniformly mixed by using a horizontal ball mill, and a slurry is obtained. The rotation speed of the horizontal ball mill is 50 rpm, the time length is 10 h, the material of the ball mill tank is zirconium oxide, and the ball-to-material ratio is 2.5:1.

[0077] The slurry is placed into an oven and dried at 100 ℃, and then is crushed and sieved through a 300-mesh screen to obtain a mixed powder.

[0078] The mixed powder is laid on a 150*150*8 mm thick polyacrylonitrile-based carbon fiber plate 3, and is loaded into a graphite mold of a rapid hot-pressing sintering furnace to perform electric field assisted pressure sintering. In the heating stage, the heating rate is 80 ℃ / min, the pressure is 40 MPa, and the temperature is increased to 1600 ℃; in the holding stage, the pressure is 90 MPa, and the holding time is 60 min; in the cooling stage, the cooling rate is 80 ℃ / min, the pressure is 40 MPa, and the temperature is decreased to 200 ℃; finally, the pressure is reduced to 0, and the furnace is cooled to room temperature; and a sintered body composite material is obtained. It is detected that the Vickers hardness of the sintered body composite material is 39.7 GPa, the fracture toughness is 4.86 MPa*m 1 / 2 , the bending strength is 448 MPa, the average grain size is 420 nm, and the minimum grain size is only 100 nm.

[0079] The sintered body composite material is bonded with a 150*150*6 mm UHMWPE plate by using an epoxy resin adhesive as a bonding agent, the thickness of the bonding agent is 0.2 mm, and a boron carbide composite ceramic material is obtained. It is detected that the areal density of the boron carbide composite ceramic material is 10.5 kg / m 2 . In the anti-bullet performance target test, a 12.7 mm penetrating incendiary bullet is fired at an initial bullet speed of 800 m / s at a shooting range of 30 m, the residual bullet speed is 704 m / s, and the back bulge is 26 mm.

[0080] First, the temperature is increased to 1600 ℃-1800 ℃, the pressure in the heating stage is 40 MPa-120 MPa; then, the temperature is held for 60 min-120 min, the pressure in the holding stage is 90 MPa-110 MPa; the temperature is decreased to 200 ℃, the pressure in the cooling stage is 40 MPa-60 MPa, and finally the pressure is reduced to 0, and the furnace is cooled to room temperature;

[0081] Example 2

[0082] ​The embodiment provides a boron carbide composite ceramic material and a preparation method and application thereof. Figs. 1-2

[0083] The boron oxide powder with a particle size of 0.3 μm and a purity of 99.6% is 100 g, the carbon powder is 35 g, the deionized water is 200 ml, the mixture of the dispersants sodium dodecyl sulfate and sodium hydroxymethyl cellulose is 5 g, the mixture of the binder polyvinyl alcohol and methacrylate is 6 g, and the sintering aid ZrO2 is 1 g, and the above materials are uniformly mixed by using a horizontal ball mill to obtain a slurry. The rotation speed of the horizontal ball mill is 300 rpm, the time length is 5 h, the material of the ball mill tank is zirconium oxide, and the ball-to-material ratio is 10:1.

[0084] The slurry is placed into an oven and dried at 100 DEG C, and then is crushed and sieved through a 300-mesh screen to obtain a mixed powder.

[0085] The mixed powder is laid on the 150*150*5 mm thick adhesive-based carbon fiber plate 3, and is loaded into a graphite mold of a rapid hot-pressing sintering furnace to perform electric field assisted pressure sintering. In the heating stage, the heating rate is 150 DEG C / min, the pressure is 120 MPa, and the temperature is increased to 1800 DEG C; in the holding stage, the pressure is 110 MPa, and the holding time is 120 min; in the cooling stage, the cooling rate is 100 DEG C / min, the pressure is 60 MPa, and the temperature is decreased to 200 DEG C; finally, the pressure is reduced to 0, and the furnace is cooled to room temperature, to obtain a sintered body composite material. The Vickers hardness of the sintered body composite material is 38.4 GPa, the fracture toughness is 4.39 MPa*m 1 / 2 , the bending strength is 395 MPa, the average grain size is 370 nm, and the minimum grain size is only 120 nm.

[0086] The sintered body composite material is bonded with the 150*150*7 mm glass fiber plate 4 by using an epoxy vinyl resin adhesive as a bonding agent, the bonding thickness is 1 mm, and a boron carbide composite ceramic material is obtained. The areal density of the boron carbide composite ceramic material is 11.8 kg / m 2 . In the anti-bullet performance target test, the 12.7 mm penetrating incendiary bullet is fired at an initial bullet speed of 800 m / s at a shooting range of 30 m, the residual bullet speed is 743 m / s, and the back bulge is 30 mm.

[0087] Embodiment three

[0088] The embodiment provides a boron carbide composite ceramic material and a preparation method and application thereof, as shown in Figs. 1-2

[0089] ​​Take 200 g of boron oxide powder with a particle size of 0.2 μm and a purity of 99.8%, 68 g of carbon powder, 1000 ml of deionized water, 0.3 g of dispersant sodium dodecyl sulfate, 13 g of binder polyurethane, and 2 g of sintering aid TiO2, and mix the above materials uniformly in a horizontal ball mill to obtain a slurry. The rotation speed of the horizontal ball mill is 100 rpm, the time is 8 h, the material of the ball mill tank is zirconia, and the ball-to-material ratio is 1:1.

[0090] Put the slurry into an oven and dry at 100°C, then crush and pass through a 300 mesh screen to obtain a mixed powder.

[0091] Lay the mixed powder on a 150×150×6 mm thick pitch-based carbon fiber plate 3, and put it into a graphite mold of a rapid hot-pressing sintering furnace for electric field assisted pressure sintering. In the heating stage, the heating rate is 120°C / min, the pressure is 100 MPa, and the temperature is raised to 1700°C; in the holding stage, the pressure is 100 MPa, and the holding time is 90 min; in the cooling stage, the cooling rate is 90°C / min, the pressure is 55 MPa, and the temperature is cooled to 200°C; finally, the pressure is reduced to 0, and the furnace is cooled to room temperature; a sintered body composite material is obtained. The Vickers hardness of the sintered body composite material is 38.4 GPa, the fracture toughness is 5.14 MPa·m 1 / 2 , the bending strength is 466 MPa, and the average grain size is 350 nm, with the smallest grain size being only 150 nm.

[0092] Use acrylic adhesive as the adhesive to bond the sintered body composite material with a 150×150×6.5 mm UHMWPE plate, with a bonding thickness of 0.8 mm, to prepare a boron carbide composite ceramic material. The areal density of the boron carbide composite ceramic material is 12.3 kg / m 2 . In the anti-bullet performance target test, a 12.7 mm penetrating incendiary bullet is fired at an initial bullet speed of 800 m / s at a shooting distance of 30 m, with a remaining bullet speed of 685 m / s and a back bulge of 35 mm.

[0093] Comparative Example One

[0094] Take 200 g of boron oxide powder with a particle size of 0.2 μm and a purity of 99.8%, 68 g of carbon powder, 1000 ml of deionized water, 0.3 g of dispersant sodium dodecyl sulfate, 13 g of binder polyurethane, and 2 g of sintering aid TiO2, and mix the above materials uniformly in a horizontal ball mill to obtain a slurry. The rotation speed of the horizontal ball mill is 100 rpm, the time is 8 h, the material of the ball mill tank is zirconia, and the ball-to-material ratio is 1:1. Then the slurry is dried and crushed, and passed through a 300 mesh screen to obtain a mixed powder.

[0095] The mixed powder is loaded into a graphite mold of a rapid hot-pressing sintering furnace, and electric field assisted pressure sintering is carried out. In the heating stage, the heating rate is 120 DEG C / min, and the pressure is 100 MPa; in the holding stage, the temperature is increased to 1700 DEG C, the pressure is 100 MPa, and the holding time is 90 min; in the cooling stage, the cooling rate is 90 DEG C / min, the pressure is 55 MPa, the temperature is decreased to 200 DEG C, finally the pressure is decreased to 0, and the furnace is cooled to room temperature; a boron carbide ceramic panel with a size of 150*150*6 mm is obtained. It is detected that the Vickers hardness of the boron carbide ceramic panel is 32.6 GPa, the fracture toughness is 3.51 MPa*m, the average grain size is 480 nm, and the minimum grain size is 250 nm. 1 / 2 , the bending strength is 350 MPa, and the average grain size is 480 nm.

[0096] The boron carbide ceramic panel is bonded with a 150*150*6 mm pitch-based carbon fiber plate 3 using polyurethane as the bonding agent, and the pitch-based carbon fiber plate 3 and a 150*150*7 mm Kevlar fiber plate 4 are bonded, the bonding thickness is 0.5 mm, and a boron carbide composite ceramic material is obtained.

[0097] It is detected that the areal density of the boron carbide composite ceramic material is 13.6 kg / m 2 , the 12.7 mm penetrating bullet is fired at a speed of 800 m / s, the shooting range is 30 m, and the bulletproof performance target test is carried out. The initial bullet speed is 800 m / s, the residual bullet speed is 789 m / s, and the back convexity is 50 mm.

[0098] The technical features in the claims and / or the specification of the present application can be combined, and the combination manner is not limited to the combination obtained by reference in the claims. The technical solution obtained by combining the technical features in the claims and / or the specification is also within the protection scope of the present application.

[0099] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present application are still within the scope of the technical solution of the present application.

Claims

1. A method of producing a boron carbide composite ceramic material, characterized by, It comprises the following steps: The boron oxide powder, carbon powder, deionized water, dispersant, binder and oxide sintering aid are ball-mixed uniformly to obtain a slurry; The slurry is dried, crushed and sieved to obtain a mixed powder; The mixed powder is laid on a carbon fiber plate and put into a graphite mold for electric field assisted pressure sintering to obtain a sintered body composite material; The carbon fiber surface of the sintered body composite material is bonded with the fiber plate to obtain a boron carbide composite ceramic material; The process of the electric field assisted pressure sintering is as follows: The temperature is raised to 1600-1800℃, and the pressure in the temperature raising stage is 40-120MPa; The temperature is kept for 60-120min, and the pressure in the temperature keeping stage is 90-110MPa; The temperature is lowered to 200-350℃, and the pressure in the temperature lowering stage is 40-60MPa; The temperature is lowered to room temperature in the furnace.

2. The production method according to claim 1, characterized by, The temperature raising rate is 80-150℃ / min, and the temperature lowering rate is 80-100℃ / min.

3. The preparation method according to claim 1, wherein the particle size of the mixed powder is less than 300 mesh; and / or the dispersant is at least one of tetramethylammonium hydroxide, glyceryl tristearate, sodium hexametaphosphate, polyacrylamide, polyvinylpyrrolidone, sodium dodecyl sulfate, sodium hydroxymethyl cellulose, phosphate ester and polyethylene glycol; and / or the binder is at least one of polyvinyl alcohol, polyvinyl butyral, methacrylate, cellulose, polyurethane, polyisobutylene and water-soluble phenol formaldehyde resin; and / or the sintering aid is at least one of Al2O3, Y2O3, TiO2 and ZrO2. The mass ratio of the boron oxide powder to the carbon powder is (2-3):

1. The sum of the mass of the boron oxide powder and the mass of the carbon powder is 1, the mass of the deionized water is 1-5, the mass of the dispersant is 0.001-0.1, the mass of the binder is 0.01-0.05, and the mass of the sintering aid is 0-0.

1. The specific method of the ball-mixing is as follows: the ball-mixing is carried out by using a horizontal ball mill, the rotating speed is 50-200rpm, the time length is 0.5-10h, and the ball-to-material ratio is (10-1):

1. The type of the carbon fiber plate is at least one of polyacrylonitrile-based carbon fiber, viscose-based carbon fiber, pitch-based carbon fiber, lignin-based carbon fiber and grown carbon fiber, and the thickness of the carbon fiber plate is 1-10mm.

4. The preparation method according to claim 1, characterized in that, The type of the fiber plate is ultra-high molecular weight polyethylene fiber, aramid fiber, Kevlar fiber or glass fiber, and the thickness of the fiber plate is 6-7mm.

5. The preparation method according to claim 1, characterized in that, The carbon fiber surface of the sintered body composite material is bonded with the fiber plate by using an adhesive to obtain a boron carbide composite ceramic material.

6. The preparation method according to claim 1, characterized in that, The type of the adhesive is epoxy resin adhesive, epoxy vinyl resin adhesive, polyurethane adhesive or acrylic adhesive, and the bonding thickness is 0.2-1mm.

7. The preparation method according to claim 1, characterized in that, 9. A boron carbide composite ceramic material prepared by the method of any one of claims 1-8.

10. Use of the boron carbide composite ceramic material of claim 9 in the field of protection.

8. The method of claim 1, wherein, ​ ​ ​ ​

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