Super-performance silicon carbide-graphite composite material

Abstract

The invention discloses a super-performance silicon carbide-graphite composite material, which is composed of silicon carbide, graphite, an auxiliary agent, alumina, nickel powder, polyimide, nanometer silicon oxide, molybdenum disulfide, glass fiber and diatomite, and relates to the technical field of composite materials. A compact silicon carbide oxidation film formed at a high temperature provides excellent oxidation resistance, the stability of the graphite base in a high-temperature environment is effectively protected, and oxidation hazards are prevented; secondly, the high acid and alkali resistance of the silicon carbide coating ensures the stability and structural integrity of the material in a corrosive environment, so that the excellent performance of the material is kept for a long time; the method plays an important role in the fields of aerospace, automobile manufacturing, electronic industry and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials, and particularly relates to a super-performance silicon carbide-graphite composite material. Background Art

[0002] With the continuous development of modern materials science, super-performance composite materials have been widely used in the fields of aerospace, automotive manufacturing, energy equipment, etc. due to their unique physical and chemical properties. In these applications, silicon carbide-graphite composite materials have attracted much attention due to their high wear resistance, high heat resistance, good electrical and thermal conductivity, and high strength.

[0003] Silicon carbide (SiC) is a ceramic material with high hardness, good wear resistance, and high temperature resistance, while graphite is widely used due to its good lubricity and electrical conductivity. However, single silicon carbide or graphite materials may not meet all performance requirements in some applications. Therefore, researchers have prepared silicon carbide-graphite composite materials with the advantages of both by compounding silicon carbide and graphite.

[0004] In the existing preparation technologies of silicon carbide-graphite composite materials, the performance of the composite materials is usually optimized by adjusting the ratio and particle size of silicon carbide and graphite. However, the composite materials prepared by these traditional methods still have deficiencies in performance, such as strength, toughness, electrical and thermal conductivity, etc. in some specific applications. Summary of the Invention

[0005] The purpose of the present invention is to provide a super-performance silicon carbide-graphite composite material to solve the problems mentioned in the above background art.

[0006] To achieve the above purpose, the present invention provides the following technical solution: A super-performance silicon carbide-graphite composite material is composed of silicon carbide, graphite, additives, alumina, nickel powder, polyimide, nano-silica, molybdenum disulfide, glass fiber, and diatomite. The preparation of this composite material involves raw materials with the following weight percentages: silicon carbide accounts for 50%-80%, graphite accounts for 10%-30%, additives account for 10%-20%, alumina accounts for 5%-10%, nickel powder accounts for 1%-5%, polyimide accounts for 3%-8%, nano-silica accounts for 1%-3%, molybdenum disulfide accounts for 1%-3%, glass fiber accounts for 2%-5%, and diatomite accounts for 1%-3%.

[0007] Preferably, the particle size of the silicon carbide is 100 mesh to 500 mesh, and the purity of the silicon carbide is higher than 99%.

[0008] Preferably, the layer spacing of the graphite is preferably 0.335nm to 0.365nm.

[0009] Preferably, the additives include one or more of carbon fiber, carbon nanotube, and silane coupling agent.

[0010] Preferably, the particle size of the alumina is less than 5 μm, and the purity is greater than 99.5%.

[0011] Preferably, the particle size of the nickel powder is less than 50 nm, the purity is greater than 99.9%, the molecular weight of the polyimide is 50,000 - 100,000, the particle size of the nano-silica is less than 100 nm, the purity is greater than 99.9%, the particle size of the molybdenum disulfide is less than 2 μm, the purity is greater than 99%, the length of the glass fiber is 3 - 12 mm, the diameter is 10 - 20 μm, and the particle size of the diatomite is less than 10 μm, and the purity is greater than 98%.

[0012] Preferably, the compressive strength of the composite material ≥ 500 MPa; the flexural strength ≥ 400 MPa; the thermal conductivity ≥ 150 W / (m·K); the electrical conductivity ≥ 100 S / cm.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: The dense silicon carbide oxide film formed at high temperature in the present invention provides excellent antioxidant performance, effectively protects the stability of the graphite base in a high-temperature environment, and prevents oxidation hazards; Secondly, the high acid and alkali resistance of the silicon carbide coating ensures the stability and structural integrity of the material in a corrosive environment, enabling it to maintain excellent performance for a long time; Thirdly, the silicon carbide coating with high thermal conductivity significantly improves the thermal conductivity of the graphite base, enabling the material to quickly dissipate heat in a high-temperature environment, improving the heat conduction efficiency, and reducing thermal stress and thermal damage; In addition, the excellent hardness and wear resistance of the silicon carbide coating significantly enhance the wear resistance of the substrate, especially suitable for components working for a long time or in a harsh environment; The characteristic of low friction coefficient effectively reduces the friction loss and improves the use efficiency of the substrate, which is particularly important in lubrication-difficult environments such as high temperature and high pressure; The excellent electrical conductivity and electrical bridge effect of the silicon carbide coating optimize the electrical properties of the substrate. Through the improvement of the above properties, the silicon carbide coating technology can significantly enhance the stability of graphite and extend its service life. The present invention plays an important role in the fields of aerospace, automotive manufacturing, electronics industry, etc. Description of the Drawings

[0014] Figure 1 It is a combined structural schematic diagram of the present invention.

[0015] 1. Silicon carbide; 2. Graphite; 3. Auxiliary agent; 4. Alumina; 5. Nickel powder; 6. Polyimide; 7. Nano-silica; 8. Molybdenum disulfide; 9. Glass fiber; 10. Diatomite; Detailed Embodiments

[0016] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0017] Please refer to Figure 1 , the present invention provides a super-performance silicon carbide-graphite composite material, which is composed of silicon carbide 1, graphite 2, additives 3, alumina 4, nickel powder 5, polyimide 6, nano-silica 7, molybdenum disulfide 8, glass fiber 9, and diatomite 10. The preparation of the composite material involves the following raw materials in weight percentages: silicon carbide 1 accounts for 50%-80%, graphite 2 accounts for 10%-30%, additives 3 account for 10%-20%, alumina 4 accounts for 5%-10%, nickel powder 5 accounts for 1%-5%, polyimide 6 accounts for 3%-8%, nano-silica 7 accounts for 1%-3%, molybdenum disulfide 8 accounts for 1%-3%, glass fiber 9 accounts for 2%-5%, and diatomite 10 accounts for 1%-3%.

[0018] Specifically, the particle size of silicon carbide 1 is 100 mesh to 500 mesh, and the purity of silicon carbide 1 is higher than 99%.

[0019] Specifically, the interlayer spacing of graphite 2 is preferably 0.335 nm to 0.365 nm.

[0020] Specifically, the additives 3 include one or more of carbon fiber, carbon nanotube, and silane coupling agent.

[0021] Specifically, the particle size of alumina 4 is less than 5 microns, and the purity is greater than 99.5%.

[0022] Specifically, the particle size of nickel powder 5 is less than 50 nm, the purity is greater than 99.9%, the molecular weight of polyimide 6 is 50,000 - 100,000, the particle size of nano-silica 7 is less than 100 nm, the purity is greater than 99.9%, the particle size of molybdenum disulfide 8 is less than 2 microns, the purity is greater than 99%, the length of glass fiber 9 is 3 - 12 mm, the diameter is 10 - 20 microns, the particle size of diatomite 10 is less than 10 microns, and the purity is greater than 98%.

[0023] Specifically, the compressive strength of the composite material ≥ 500 MPa; the flexural strength ≥ 400 MPa; the thermal conductivity ≥ 150 W / (m·K); the electrical conductivity ≥ 100 S / cm.

[0024] Although embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A super performance silicon carbide-graphite composite material, characterized in that: The composite material is composed of silicon carbide (1), graphite (2), an auxiliary agent (3), aluminum oxide (4), nickel powder (5), polyimide (6), nano silicon oxide (7), molybdenum disulfide (8), glass fiber (9) and diatomaceous earth (10), wherein the preparation of the composite material involves the following raw materials in weight percentage: silicon carbide (1) accounts for 50%-80%, graphite (2) accounts for 10%-30%, the auxiliary agent (3) accounts for 10%-20%, aluminum oxide (4) accounts for 5%-10%, nickel powder (5) accounts for 1%-5%, polyimide (6) accounts for 3%-8%, nano silicon oxide (7) accounts for 1%-3%, molybdenum disulfide (8) accounts for 1%-3%, glass fiber (9) accounts for 2%-5% and diatomaceous earth (10) accounts for 1%-3%.

2. The ultra-performance silicon carbide-graphite composite material according to claim 1, characterized in that: The particle size of the silicon carbide (1) is 100 mesh to 500 mesh, and the purity of the silicon carbide (1) is higher than 99%.

3. The ultra-performance silicon carbide-graphite composite material according to claim 1, characterized in that: The interlayer distance of the graphite (2) is preferably 0.335 nm to 0.365 nm.

4. The ultra-performance silicon carbide-graphite composite material according to claim 1, characterized in that: The auxiliary agent (3) includes one or more of carbon fiber, carbon nanotube, and silane coupling agent.

5. The ultra-performance silicon carbide-graphite composite material according to claim 1, characterized in that: The particle size of the aluminum oxide (4) is less than 5 microns and the purity is greater than 99.5%.

6. The ultra-performance silicon carbide-graphite composite material according to claim 1, characterized in that: The nickel powder (5) has a particle size of less than 50 nanometers and a purity of more than 99.9%, the polyimide (6) has a molecular weight of 50,000-100,000, the nano-silicon oxide (7) has a particle size of less than 100 nanometers and a purity of more than 99.9%, the molybdenum disulfide (8) has a particle size of less than 2 micrometers and a purity of more than 99%, the glass fiber (9) has a length of 3-12 millimeters and a diameter of 10-20 micrometers, and the diatomaceous earth (10) has a particle size of less than 10 micrometers and a purity of more than 98%.

7. A super performance silicon carbide-graphite composite material according to claim 1, 2, 3 or 4, characterized in that: The composite material has a compressive strength of ≥500 MPa; a flexural strength of ≥400 MPa; a thermal conductivity of ≥150 W / (m·K); and an electrical conductivity of ≥100 S / cm.

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