Seamless splicing type constraint reinforced boron carbide bulletproof ceramic and preparation method thereof
By combining seamless splicing structure and phase change additives, the problems of interface failure and insufficient resistance to multiple strikes of boron carbide bulletproof ceramics are solved, and high interface stability and low-cost manufacturing are achieved.
Patent Information
- Application Number
- CN202510959743.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-11
- Publication Date
- 2025-09-16
AI Technical Summary
Existing boron carbide bullet-proof ceramics have insufficient ability to resist multiple bullets when formed as a whole, and the spliced structure has the risk of interface failure. The existing strengthening and toughening technology has limited improvements and is difficult to adapt to large-scale production.
A seamless splicing structure is adopted. By coating phase change additives at the joints, temperature-induced phase change is used to form compressive stress, and prestressed directional control technology is combined to prepare boron carbide ceramics with optimized multi-level particle size distribution.
The weak area of stress concentration at the joint is eliminated, and the impact energy is evenly dissipated along the interface, thereby improving the resistance to multiple strikes and interface stability of the boron carbide bulletproof ceramic and reducing production costs.
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Figure CN120647382A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of bulletproof ceramic material preparation, and in particular to a seamlessly spliced constrained reinforced boron carbide bulletproof ceramic and a preparation method thereof. Background Art
[0002] Boron carbide bulletproof ceramics are the core material of lightweight bulletproof equipment. Their performance optimization faces the dual challenges of structural design and enhancement of basic material properties. In the current mainstream solution, the integrally formed ceramics are insufficient in resistance to multiple bullets due to stress diffusion. Although the spliced structure alleviates this problem through block design, it causes the risk of interface failure due to stress concentration at the joints. Although the existing technology proposes the use of a multi-layer stacking process, this process can disperse the energy of the bullet, but the problems of staggered joints and sliding between layers significantly reduce the process stability and bulletproof reliability. In addition, the existing densification, in-situ crystal phase or the introduction of reinforcing phase and other strengthening and toughening technologies have limited improvement on the mechanical properties of ceramics. Although the prestressed reinforcement method can offset the external load through surface compressive stress, it is limited by the complex process of six-sided coating and is difficult to adapt to large-scale production needs.
[0003] Therefore, how to break through the traditional toughening path, eliminate the weak interface area through seamless splicing structure, combine multi-level particle grading optimization (such as micron-nano dual-scale filling) and prestressed directional control technology to construct a boron carbide ceramic system with multiple impact resistance, high interface stability and low-cost manufacturing potential, thereby breaking through the dual bottlenecks of bulletproof materials' multiple impact resistance and reliability, has become an urgent problem to be solved in this field. Summary of the Invention
[0004] The present application proposes a method for preparing seamlessly spliced constrained reinforced boron carbide bullet-proof ceramics, comprising the following steps: step S1, subjecting raw material powder and additives to ball milling and spray granulation to prepare ceramic granulation powder; step S2, dry-pressing the ceramic granulation powder to form a quadrilateral ceramic blank; step S3, brushing the sides of the ceramic blank with a binder mixed with a phase change additive, and then tightly splicing them in a graphite mold; step S4, placing the graphite mold containing the ceramic blank into a sintering furnace, and sintering to prepare the constrained reinforced boron carbide bullet-proof ceramic.
[0005] The preparation method of the seamless spliced constrained reinforced boron carbide bulletproof ceramic described above, wherein the raw material powder is composed of 86wt%-99wt% of boron carbide powder with a particle size of 0.5-2.5um and 1wt%-14wt% of zirconium oxide powder with a particle size of 0.1-0.3um.
[0006] In the method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramics as described above, the auxiliary agent is a polyvinyl alcohol binder, and the mass ratio of the auxiliary agent to the raw material powder is 0.02-0.15.
[0007] In the method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic as described above, the length of opposite sides of the ceramic blank is 20 mm to 100 mm, and the thickness is 6 mm to 40 mm.
[0008] In the method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic as described above, the binder is a mixture of any one or more of polyvinyl alcohol, phenolic resin, epoxy resin, and polyurethane.
[0009] The method for preparing the seamlessly spliced constrained reinforced boron carbide bulletproof ceramic as described above, wherein a binder mixed with a phase change additive is brushed on the side of the ceramic blank and then tightly spliced in a graphite mold, comprises uniformly mixing 10wt%-40wt% of silicon carbide powder with a particle size of 0.2-1.4um and 1wt%-4wt% of zirconium oxide powder with a particle size of 0.1-0.3um with the binder, and the ratio of the powder to the binder is 20:80 to 40:60 by mass.
[0010] In the method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic as described above, the sintering process is either vacuum hot pressing sintering or spark plasma hot pressing sintering.
[0011] The preparation method of the seamless spliced constrained reinforced boron carbide bulletproof ceramic as described above, wherein during the manufacturing process, the debinding temperature is 600-700°C, the debinding time is 2-3 hours, the sintering temperature is 1900-2200°C, the insulation time is 120-240 minutes, the sintering pressure is 0-50 MPa, and the holding time is 0-120 minutes.
[0012] A method for preparing seamlessly spliced constrained reinforced boron carbide bulletproof ceramics comprises the following steps: step Q1, subjecting raw material powder and additives to ball milling and spray granulation to prepare ceramic granulated powder; step Q2, dry-pressing the ceramic granulated powder to form a hexagonal ceramic blank; step Q3, brushing the sides of the ceramic blank with a binder mixed with a phase change additive, and then tightly splicing them in a graphite mold; step Q4, placing the graphite mold containing the ceramic blanks in a sintering furnace, and sintering to prepare the constrained reinforced boron carbide bulletproof ceramic.
[0013] A seamless spliced constrained reinforced boron carbide bulletproof ceramic is manufactured by any of the above-mentioned methods for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic.
[0014] This application has the following beneficial effects:
[0015] This application produces constrained-reinforced boron carbide ceramics by splicing quadrilateral or hexagonal boron carbide ceramic blanks together, coating the joints with a phase change additive, and utilizing temperature-induced phase transition to create compressive stress at the joints. This seamless splicing structure completely eliminates the stress concentration zones found in traditional joints. Combined with prestressed directional control technology, this allows for uniform dissipation of impact energy along the interface without the risk of interlayer misalignment, significantly enhancing the boron carbide bulletproof ceramic's ability to withstand multiple strikes. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.
[0017] Figure 1 Flowchart of the method for preparing seamless spliced constrained reinforced boron carbide bulletproof ceramics provided in an embodiment of the present application.
[0018] Figure 2 A schematic diagram of the ceramic green body structure in the method for preparing seamlessly spliced constrained reinforced boron carbide bullet-proof ceramics provided in an embodiment of the present application;
[0019] Figure 3 Another flow chart of the method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic provided in an embodiment of the present application.
[0020] Figure 4 Another structural diagram of the ceramic blank in the preparation method of the seamless splicing constrained reinforced boron carbide bulletproof ceramic provided in the embodiment of the present application DETAILED DESCRIPTION
[0021] The following is a clear and complete description of the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.
[0022] This application produces seamless, constrained, reinforced boron carbide ceramics by coating the joints of quadrilateral or hexagonal boron carbide ceramic blanks with a phase change additive and inducing compressive stress at the joints through high-temperature sintering. The preparation method for this biomimetic layered bulletproof ceramic is described in detail below, using several examples.
[0023] Example 1
[0024] Step S1: preparing ceramic granulated powder by ball milling and spray granulation process with raw material powder and additives.
[0025] The raw material powder is determined according to mass percentage, specifically consisting of 86wt%-99wt% of boron carbide powder with a particle size of 0.5-2.5um and 1wt%-14wt% of zirconium oxide powder with a particle size of 0.1-0.3um.
[0026] The auxiliary agent is a polyvinyl alcohol binder, and the mass ratio of the auxiliary agent to the raw material powder is 0.02-0.15.
[0027] As a specific example of the present invention, 19.8 kg of 2.0 μm boron carbide powder and 0.2 kg of 0.3 μm zirconium oxide powder were weighed and placed in a ball mill. 20 kg of grinding balls and 30 kg of deionized water were added. After ball milling for 4 hours, 0.6 kg of polyvinyl alcohol binder was added and ball milling continued for 12 hours. The ball-milled ceramic slurry was spray granulated to a particle size range of 40-120 μm.
[0028] Step S2: dry-pressing the ceramic granulated powder to form a quadrilateral ceramic blank.
[0029] The length of opposite sides of the ceramic blank is 20mm to 100mm, and the thickness is 6mm to 40mm.
[0030] As a specific embodiment of the present invention, the ceramic granulated powder is dry pressed to form a quadrilateral ceramic blank with opposite sides of 50 mm and a thickness of 15 mm. Figure 2 FIG. 1 is a schematic diagram of the structure of a quadrilateral ceramic blank according to the present embodiment.
[0031] Step S3: Brush the side edges of the ceramic blank with a binder mixed with a phase change additive, and then tightly splice them in a graphite mold.
[0032] The binder is a mixture of any one or more of polyvinyl alcohol, phenolic resin, epoxy resin and polyurethane.
[0033] After determining the binder, 10wt%-40wt% of silicon carbide powder with a particle size of 0.2-1.4um and 1wt%-4wt% of zirconium oxide powder with a particle size of 0.1-0.3um are evenly mixed with the binder, and the ratio of powder to binder is 20:80 to 40:60 by mass.
[0034] As a specific embodiment of the present invention, 190 g of silicon carbide powder with a particle size of 1.0 μm and 10 g of zirconium oxide powder with a particle size of 0.3 μm were evenly mixed with 400 g of phenolic resin binder, then evenly brushed on the side of the ceramic blank and tightly spliced in a graphite mold.
[0035] Step S4: placing the graphite mold containing the ceramic blank into a sintering furnace, and sintering to produce constrained reinforced boron carbide bulletproof ceramics.
[0036] The sintering process is either vacuum hot pressing sintering or spark plasma hot pressing sintering.
[0037] During the manufacturing process, the debinding temperature is 600-700°C, the debinding time is 2-3h, the sintering temperature is 1900-2200°C, the heat preservation time is 120-240min, the sintering pressure is 0-50MPa, and the pressure holding time is 0-120min.
[0038] As a specific embodiment of the present invention, a graphite mold containing a ceramic blank is placed in a vacuum hot pressing sintering furnace, debinding is carried out at 600°C for 3 hours, the sintering temperature is 2060°C, the heat preservation time is 120 minutes, the sintering pressure is 30 MPa, and the holding time is 120 minutes to produce a seamless spliced constrained reinforced boron carbide bulletproof ceramic.
[0039] The following describes a method for preparing boron carbide ceramics by splicing together a whole block of boron carbide ceramic greenware. Specifically, 19 kg of 2.0 μm boron carbide powder and 1 kg of 0.3 μm zirconium oxide powder were weighed and placed in a ball mill. 20 kg of grinding balls and 30 kg of deionized water were added. After ball milling for 4 hours, 1.2 kg of polyvinyl alcohol binder was added and ball milling continued for 12 hours. The ball-milled ceramic slurry was spray granulated to a particle size range of 40-120 μm. The granulated ceramic powder was dry-pressed to form a whole block of ceramic greenware measuring 250 mm x 300 mm and 15 mm thick. The graphite mold containing the ceramic greenware was placed in a vacuum hot-pressing sintering furnace. The mixture was debinded at 600°C for 3 hours, sintered at 2080°C for 180 minutes, and sintered at a pressure of 50 MPa for 120 minutes to produce the boron carbide bulletproof ceramic.
[0040] By using the method described above in this embodiment, quadrilateral boron carbide ceramic blanks are spliced together, and a phase change additive is applied to the joints. Temperature-induced phase change is used to form compressive stress at the joints, thereby producing constrained reinforced boron carbide ceramics. Compared to preparing boron carbide ceramics by splicing together a whole block of boron carbide ceramic blanks, the seamless splicing structure provided by this embodiment completely eliminates the stress concentration weak areas at traditional joints. Combined with prestressed directional control technology, the impact energy is evenly dissipated along the interface without the risk of interlayer misalignment, significantly improving the boron carbide bulletproof ceramic's ability to withstand multiple strikes.
[0041] Example 2
[0042] Step Q1: The raw material powder and the additive are subjected to ball milling and spray granulation processes to prepare ceramic granulated powder.
[0043] The raw material powder is determined according to mass percentage, specifically consisting of 86wt%-99wt% of boron carbide powder with a particle size of 0.5-2.5um and 1wt%-14wt% of zirconium oxide powder with a particle size of 0.1-0.3um.
[0044] The auxiliary agent is a polyvinyl alcohol binder, and the mass ratio of the auxiliary agent to the raw material powder is 0.02-0.15.
[0045] As a specific example of the present invention, 18 kg of boron carbide powder with a particle size of 0.5 μm and 2 kg of zirconium oxide powder with a particle size of 0.1 μm were weighed and placed in a ball mill. 20 kg of grinding balls and 30 kg of deionized water were added. After ball milling for 4 hours, 0.8 kg of polyvinyl alcohol binder was added and ball milling continued for 12 hours. The ball-milled ceramic slurry was spray granulated to a particle size range of 40-120 μm.
[0046] Step Q2: dry-pressing the ceramic granulated powder to form a hexagonal ceramic blank.
[0047] The length of opposite sides of the ceramic blank is 20mm to 100mm, and the thickness is 6mm to 40mm.
[0048] As a specific embodiment of the present invention, the ceramic granulated powder is dry pressed to form a hexagonal ceramic blank with a side width of 50 mm and a thickness of 15 mm. Figure 4 FIG. 1 is a schematic diagram of the hexagonal ceramic green body structure of this embodiment.
[0049] Step Q3: Brush the side of the ceramic blank with a binder mixed with a phase change additive, and then tightly splice them in a graphite mold.
[0050] The binder is a mixture of any one or more of polyvinyl alcohol, phenolic resin, epoxy resin and polyurethane.
[0051] After determining the binder, 10wt%-40wt% of silicon carbide powder with a particle size of 0.2-1.4um and 1wt%-4wt% of zirconium oxide powder with a particle size of 0.1-0.3um are evenly mixed with the binder, and the ratio of powder to binder is 20:80 to 40:60 by mass.
[0052] As a specific embodiment of the present invention, 190 g of silicon carbide powder with a particle size of 0.5 μm and 10 g of zirconium oxide powder with a particle size of 0.1 μm were evenly mixed with 400 g of polyvinyl alcohol binder, then evenly brushed on the side of the ceramic blank and tightly spliced in a graphite mold.
[0053] Step Q4: placing the graphite mold containing the ceramic blank into a sintering furnace, and sintering to produce constrained reinforced boron carbide bulletproof ceramics.
[0054] The sintering process is either vacuum hot pressing sintering or spark plasma hot pressing sintering.
[0055] During the manufacturing process, the debinding temperature is 600-700°C, the debinding time is 2-3h, the sintering temperature is 1900-2200°C, the heat preservation time is 120-240min, the sintering pressure is 0-50MPa, and the pressure holding time is 0-120min.
[0056] As a specific embodiment of the present invention, a graphite mold containing a ceramic blank is placed in a vacuum hot pressing sintering furnace, the binder is removed at 700°C for 3 hours, the sintering temperature is 2020°C, the heat preservation time is 90 minutes, the sintering pressure is 40 MPa, and the holding time is 90 minutes to produce a seamless spliced constrained reinforced boron carbide bulletproof ceramic.
[0057] The following describes a method for preparing boron carbide ceramics by splicing together a whole block of boron carbide ceramic greenware. Specifically, 19 kg of 2.0 μm boron carbide powder and 1 kg of 0.3 μm zirconium oxide powder were weighed and placed in a ball mill. 20 kg of grinding balls and 30 kg of deionized water were added. After ball milling for 4 hours, 1.2 kg of polyvinyl alcohol binder was added and ball milling continued for 12 hours. The ball-milled ceramic slurry was spray granulated to a particle size range of 40-120 μm. The granulated ceramic powder was dry-pressed to form a whole block of ceramic greenware measuring 250 mm x 300 mm and 15 mm thick. The graphite mold containing the ceramic greenware was placed in a vacuum hot-pressing sintering furnace. The mixture was debinded at 600°C for 3 hours, sintered at 2080°C for 180 minutes, and sintered at a pressure of 50 MPa for 120 minutes to produce the boron carbide bulletproof ceramic.
[0058] By using the method described above in this embodiment, hexagonal boron carbide ceramic blanks are spliced together, and a phase change additive is applied to the joints. Temperature-induced phase change is used to form compressive stress at the joints, thereby producing constrained reinforced boron carbide ceramics. Compared to preparing boron carbide ceramics by splicing together entire pieces of boron carbide ceramic blanks, the seamless splicing structure provided by this embodiment completely eliminates the stress concentration weak areas at traditional joints. Combined with prestressed directional control technology, the impact energy is evenly dissipated along the interface without the risk of interlayer misalignment, significantly improving the boron carbide bulletproof ceramic's ability to withstand multiple strikes.
[0059] This application has the following beneficial effects:
[0060] This application produces constrained-reinforced boron carbide ceramics by splicing quadrilateral or hexagonal boron carbide ceramic blanks together, coating the joints with a phase change additive, and utilizing temperature-induced phase transition to create compressive stress at the joints. This seamless splicing structure completely eliminates the stress concentration zones found in traditional joints. Combined with prestressed directional control technology, this allows for uniform dissipation of impact energy along the interface without the risk of interlayer misalignment, significantly enhancing the boron carbide bulletproof ceramic's ability to withstand multiple strikes.
[0061] Although the present application has been described with reference to examples, this is for illustrative purposes only and is not intended to limit the present application, and changes, additions and / or deletions to the embodiments may be made without departing from the scope of the present application.
[0062] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.
Claims
1. A method for preparing seamless spliced constrained reinforced boron carbide bulletproof ceramics, characterized in that: The following steps are involved: Step S1, preparing ceramic granulated powder by ball milling and spray granulation process with raw material powder and additives; Step S2, dry-pressing the ceramic granulated powder to form a quadrilateral ceramic blank; Step S3: Brush the sides of the ceramic blank with a binder mixed with a phase change additive, and then tightly splice them in a graphite mold; Step S4: placing the graphite mold containing the ceramic blank into a sintering furnace, and sintering to produce constrained reinforced boron carbide bulletproof ceramics.
2. The method for preparing the seamless splicing constrained reinforced boron carbide bulletproof ceramic according to claim 1, characterized in that: The raw material powder consists of 86wt%-99wt% of boron carbide powder with a particle size of 0.5-2.5um and 1wt%-14wt% of zirconium oxide powder with a particle size of 0.1-0.3um.
3. The method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic according to claim 1, wherein: The auxiliary agent is a polyvinyl alcohol binder, and the mass ratio of the auxiliary agent to the raw material powder is 0.02-0.
15.
4. The method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic according to claim 1, wherein: The length of opposite sides of the ceramic blank is 20 mm to 100 mm, and the thickness is 6 mm to 40 mm.
5. The method for preparing the seamless splicing constrained reinforced boron carbide bulletproof ceramic according to claim 1, wherein: The binder is a mixture of any one or more of polyvinyl alcohol, phenolic resin, epoxy resin and polyurethane.
6. The method for preparing the seamless splicing constrained reinforced boron carbide bulletproof ceramic according to claim 1, characterized in that: The sides of the ceramic blank are brushed with a binder mixed with a phase change additive, and then tightly spliced in a graphite mold, including mixing 10wt%-40wt% of silicon carbide powder with a particle size of 0.2-1.4um and 1wt%-4wt% of zirconium oxide powder with a particle size of 0.1-0.3um with the binder, with the ratio of powder to binder being 20:80 to 40:60 by mass.
7. The method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic according to claim 1, wherein: The sintering process is either vacuum hot pressing sintering or spark plasma hot pressing sintering.
8. The method for preparing the seamless spliced constrained reinforced boron carbide bulletproof ceramic according to claim 1, wherein: During the manufacturing process, the debinding temperature is 600-700°C, the debinding time is 2-3h, the sintering temperature is 1900-2200°C, the holding time is 120-240min, the sintering pressure is 0-50MPa, and the holding time is 0-120min.
9. A method for preparing seamless spliced constrained reinforced boron carbide bulletproof ceramics, characterized in that: The following steps are involved: Step Q1, preparing ceramic granulated powder by ball milling and spray granulation process with raw material powder and additives; Step Q2, dry-pressing the ceramic granulated powder to form a hexagonal ceramic blank; Step Q3: Brush the sides of the ceramic blank with a binder mixed with a phase change additive, and then tightly splice them in a graphite mold; Step Q4: placing the graphite mold containing the ceramic blank into a sintering furnace, and sintering to produce constrained reinforced boron carbide bulletproof ceramics.
10. A seamless spliced constrained reinforced boron carbide bulletproof ceramic, characterized in that: The ceramic is made by the preparation method of seamless splicing constrained reinforced boron carbide bulletproof ceramic according to any one of claims 1 to 9.