Electrically conductive corrosion resistant carbon-carbon composite, method of making and use thereof

Abstract

The application relates to the technical field of new materials, and discloses a carbon-carbon composite material with electric conductivity and corrosion resistance as well as a preparation method and application thereof. The carbon-carbon composite material comprises single carbon fibers and multi-layered graphite sheets surrounding the periphery of the single carbon fibers, and nano metal particles are filled between any two adjacent graphite sheets, wherein the nano metal particles contain copper elements, iron elements, aluminum elements and optional IVB group metal elements. The carbon-carbon composite material disclosed by the application is composed of layered graphite sheet clusters with a concentric circle structure in a microscale, the interior of the carbon-carbon composite material contains nano metal particles in addition to carbon, and the metal elements are uniformly distributed in the graphite sheet clusters with a specific structure in an atomic scale; the carbon-carbon composite material with the characteristics has excellent electric conductivity and corrosion resistance.

Description

Technical Field

[0001] This invention relates to the field of new materials technology, specifically to a conductive and corrosion-resistant carbon-carbon composite material, its preparation method, and its application. Background Technology

[0002] Carbon fiber possesses a comprehensive set of properties, including high tensile strength, high tensile modulus, low density, high temperature resistance, ablation resistance, corrosion resistance, high electrical and thermal conductivity, low thermal expansion, self-lubrication, and good biocompatibility. It is widely used in aerospace, automotive, building energy, and sporting goods industries. In Chapter 5, "Graphite Fiber," of He Fu's book *Carbon Fiber and Graphite Fiber* (first edition, September 2010), it states that graphite fiber generally refers to carbon fiber with a carbon content of over 99%. Graphite fiber can be obtained by graphitizing carbon fiber at high temperatures of 2200–3000℃. Graphite fiber not only has a high carbon content but also a high tensile modulus. It exhibits excellent properties such as a low coefficient of thermal expansion, good thermal stability, and dimensional stability, making it suitable for manufacturing rigid, thin, and dimensionally stable composite materials, widely used in aerospace applications, particularly in spacecraft. For example, high-modulus carbon fiber composites are used to manufacture the horn antennas of artificial satellites to ensure dimensional stability in the temperature-changing environment of space.

[0003] Carbon-carbon (C / C) composites refer to multiphase structural materials with carbon fibers or their fabrics as the reinforcing phase and pyrolytic carbon through chemical vapor infiltration or resin carbon or pitch carbon impregnated and carbonized through liquid phase as the matrix (domestic patent: CN112125690A). They possess extremely high specific strength and specific modulus, and can be used at temperatures above 2000℃ in an inert atmosphere without degradation of mechanical properties, exhibiting characteristics unmatched by any other material. C / C composites are non-melting and non-flammable, exhibit uniform ablation, and are widely used in the outer wall materials of space shuttles, missile nose cones, and engine nozzles. C / C composites are excellent thermal conductors with a low coefficient of thermal expansion, and are resistant to friction and wear, making them widely used in aircraft braking systems. C / C composites are prepared by densifying preforms made from carbon fiber filaments or short-cut carbon fiber composite matrix carbon through liquid phase impregnation and carbonization or chemical vapor deposition and chemical vapor infiltration.

[0004] The fabrication of carbon-carbon composite materials integrates high-temperature technology and equipment. The key to its continuous graphitization preparation lies in suppressing and controlling the high-temperature oxidation and biochemical (evaporation) of the graphite heating element and the running fibers. Carbon-carbon composite materials exhibit macroscopically diverse morphologies due to their different stacking / arrangement in three-dimensional space. These diverse carbon materials are composed of microcrystals of varying sizes and orientations, and stacking states. Catalytically grown carbon nanofibers exhibit a variety of morphologies; different catalysts and raw materials produce tubular, herringbone-like, and planar carbon nanofibers with different structures.

[0005] CN111807853A discloses a preparation process and application of carbon-carbon composite parts, which uses carbon fiber, vapor-deposited carbon, and impregnated carbon composites to maintain good mechanical, thermal, and tribological properties at high temperatures, reduces costs by 50%, and allows for mass production. CN112125690A uses flake graphite and UV-cured silicone to prepare a mixed colloid, which is then filled between a mixed layer of carbon fiber and glass fiber to prepare an intermediate. The carbon-carbon composite material is prepared by hot-pressing, curing, and drying, and exhibits high tensile strength and high elasticity. CN112679950A discloses a method for preparing flexible carbon-carbon composite materials. After coating the surface of carbon fiber cloth with a thermosetting resin film, hot-pressing and curing are performed, followed by carbonization in an inert atmosphere. This method has the advantages of short processing time, simple process, no need for high-pressure equipment, and high production efficiency, enabling industrial production. CN113175565A discloses a thin-walled, high-strength carbon-carbon composite pipe and its preparation method. The pipe comprises a pipe body formed by carbon cloth, binder, and CVD lamination, and a dense layer located on the inner surface of the pipe body. This pipe has the advantage of reducing wall thickness while maintaining strength. CN113636854A discloses a carbon-carbon composite material with deposited carbon nanotubes. Short-cut carbon fibers are embedded within a carbon matrix and carbon fibers, and carbon nanotubes are deposited between them. This significantly improves the mechanical properties and oxidation resistance of the carbon-carbon composite material. CN113636855A discloses an internally oxidation-resistant carbon-carbon composite material, comprising a carbon matrix, carbon fiber reinforcement distributed within the carbon matrix, silicon carbide, zirconium oxide, and alumina. This material improves the ablation resistance and service life of the composite material. CN113683437A discloses a carbon-carbon composite material containing refractory metal, comprising a carbon matrix, carbon fiber reinforcement distributed within the carbon matrix, zirconium-fullerene composite nanoparticles, and silicon-rich silicon carbide, which has the advantages of improving the composite material's ablation resistance, service life, and oxidation resistance. CN115180969A discloses a high thermal conductivity carbon-carbon composite material and its preparation method, which utilizes electrophoresis to produce graphene / AlN reinforcement on the surface and inside of a carbon fiber needle-punched preform, impregnates it in benzoxazine resin, and after thermosetting and atmospheric pressure carbonization, exhibits excellent mechanical properties and good thermal conductivity. CN115231941A relates to a carbon-carbon composite material for ultra-high temperature environments and its preparation method, comprising a carbon matrix, carbon fiber reinforcement, ultra-high temperature ceramics, and carbon nanotubes. The prepared carbon-carbon composite material has excellent mechanical properties, high-temperature ablation resistance, and good thermal conductivity. CN213628313U discloses a carbon-carbon composite material sheet, which has the advantages of being lightweight and high-strength, having high thermal conductivity and low expansion, good friction performance, good thermal shock resistance, and high dimensional stability.

[0006] Existing publicly available patent research indicates that most current research on C / C composite materials focuses on improving and optimizing their preparation processes, addressing key technical challenges related to the functional properties and applications of C / C composites. However, the finished C / C composites disclosed in existing technologies exhibit relatively limited morphology, and their main component is only carbon, resulting in poor corrosion resistance. Furthermore, there are no reports on C / C composites with high aspect ratios and fiber rod-like morphologies. Summary of the Invention

[0007] The purpose of this invention is to overcome the problems of existing carbon-carbon composite materials having a single product form, being composed mainly of carbon, and having poor corrosion resistance. This invention provides a conductive and corrosion-resistant carbon-carbon composite material, its preparation method, and its application. This carbon-carbon composite material is composed of layered graphite flakes with a concentric circle structure at the microscale. In addition to carbon, it contains nano-metal particles, and non-carbon elements are uniformly distributed at the atomic scale. This carbon-carbon composite material with these characteristics exhibits excellent conductive and corrosion-resistant properties.

[0008] To achieve the above objectives, the present invention provides a conductive and corrosion-resistant carbon-carbon composite material comprising a single carbon fiber and multiple layers of graphite sheets surrounding the single carbon fiber, wherein nano-metal particles are filled between any two adjacent layers of graphite sheets, wherein the nano-metal particles contain copper, iron, aluminum and optional group IVB metal elements.

[0009] Preferably, the carbon-carbon composite material contains 50-90% by weight of carbon, 1-15% by weight of copper, 0.5-10% by weight of iron, 0.1-5% by weight of aluminum, and 0-1% by weight of group IVB metals.

[0010] Preferably, the carbon-carbon composite material contains 60-70% by weight of carbon, 5-9% by weight of copper, 1-6% by weight of iron, 0.1-2.5% by weight of aluminum, and 0.05-0.5% by weight of group IVB metals.

[0011] Preferably, the group IVB metal element is titanium and / or zirconium.

[0012] Preferably, the nano-metal particles contain copper, iron, aluminum, and titanium.

[0013] Preferably, the number of graphite sheets surrounding the outer periphery of the single carbon fiber is 3-20 layers, more preferably 5-18 layers.

[0014] Preferably, the diameter of the single carbon fiber is 4-8 μm, more preferably 4.5-7.5 μm; and the length is 2-10 mm, more preferably 3-9 mm.

[0015] Preferably, the thickness of the multilayer graphite sheets gradually increases from the inside to the outside.

[0016] Preferably, the ratio of the total thickness of the multilayer graphite sheets to the diameter of the single carbon fiber is 1-100:1.

[0017] Preferably, the carbon-carbon composite material is in a straight or curved shape.

[0018] Preferably, at least a portion of the surface of the carbon-carbon composite material is bamboo-like and / or raised.

[0019] Preferably, the carbon-carbon composite material has a diameter of 0.02-1 mm, more preferably 0.1-0.3 mm, and a length of 0.1-10 mm, more preferably 1-5 mm.

[0020] Preferably, in the Raman spectrum of the carbon-carbon composite material, the ratio of the peak intensity of the D peak to the peak intensity of the G peak is 0.07-0.3:1.

[0021] Preferably, in the Raman spectrum of the carbon-carbon composite material, the ratio of the peak intensity of the 2D peak to the peak intensity of the G peak is 0.2-1:1.

[0022] The second aspect of the present invention provides a method for preparing a conductive and corrosion-resistant carbon-carbon composite material, the method comprising: reacting short-cut carbon fibers, a carbon source and a metal source at 1500-3500°C in the presence of an inert atmosphere, wherein the volumetric flow rate of the inert atmosphere is 20-1800 mL / min.

[0023] The metal source includes a copper source, an iron source, an aluminum source, and an optional group IVB metal source.

[0024] Preferably, the weight ratio of the metal source, the carbon source, and the chopped carbon fibers is 20-100:30-200:1, and more preferably 30-70:50-150:1;

[0025] The weight ratio of the copper source, the group IVB metal source, the iron source, and the aluminum source is 10-100:0-50:5-10:1.

[0026] Preferably, the group IVB metal source is a titanium source and / or a zirconium source.

[0027] Preferably, the metal source contains a copper source, an iron source, an aluminum source, and a titanium source.

[0028] Preferably, the copper source is selected from one or more of CuSO4, CuO, CuCl2 and Cu(OH)2.

[0029] Preferably, the iron source is selected from one or more of FeO, Fe2O3, Fe3O4, Fe(OH)2, Fe(OH)3, FeCl2, FeCl3 and FePO4.

[0030] Preferably, the aluminum source is selected from one or more of Al2O3, AlCl3, Al2(SO4)3, Al(OH)3 and AlPO4.

[0031] Preferably, the titanium source is selected from one or more of TiF4, TiF3, TiCl4, TiSO4 and TiO2.

[0032] Preferably, the carbon source is carbonized resin and / or graphite.

[0033] Preferably, the graphite is amorphous graphite.

[0034] Preferably, the reaction temperature is 1500-2800℃; the reaction time is 12-720 hours, preferably 24-120 hours; and the volumetric flow rate of the inert atmosphere is 50-500 mL / min, preferably 100-300 mL / min.

[0035] Preferably, the length of the chopped carbon fiber is 0.1-10 mm, more preferably 1-5 mm; the specification is 12-320 K, more preferably 12-48 K; and the carbon content is 85-95% by weight.

[0036] A third aspect of the present invention provides a conductive and corrosion-resistant carbon-carbon composite material prepared by the method described above.

[0037] The fourth aspect of the present invention provides the conductive and corrosion-resistant carbon-carbon composite material described above, or the application of the conductive and corrosion-resistant carbon-carbon composite material described above as a conductive and corrosion-resistant material.

[0038] The carbon-carbon composite material of the present invention is composed of layered graphite flakes with concentric circle structure at the microscale. In addition to carbon, it also contains nano-metal particles, and the metal elements are uniformly distributed at the atomic scale in the graphite flakes with a specific structure. The carbon-carbon composite material with this feature has excellent electrical conductivity and corrosion resistance.

[0039] The method for preparing conductive and corrosion-resistant carbon-carbon composite materials described in this invention is simple to operate. Short-cut carbon fibers, carbon source and metal source are mixed and reacted directly under specific conditions to obtain carbon-carbon composite materials with excellent conductivity and corrosion resistance. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the microstructure of the carbon-carbon composite material in Example 1.

[0041] Figures 2-5 The elemental distributions (elemental energy spectrum diagrams) of Cu, Fe, Al, and Ti inside the carbon-carbon composite material of Example 1 are shown.

[0042] Figure 6 This is a schematic diagram of the surface morphology of the carbon-carbon composite material in Example 1.

[0043] Figure 7 This is a schematic diagram of the cross-sectional morphology of the carbon-carbon composite material in Example 1.

[0044] Figure 8 The image shows a 3D Raman image of the cross section of the carbon-carbon composite material in Example 1 (where the Z direction is the intensity ratio of the D peak and the G peak). Detailed Implementation

[0045] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0046] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0047] The first aspect of the present invention provides a conductive and corrosion-resistant carbon-carbon composite material, the carbon-carbon composite material comprising a single carbon fiber and multiple layers of graphite sheets surrounding the single carbon fiber, wherein nano-metal particles are filled between any two adjacent layers of graphite sheets.

[0048] The carbon-carbon composite material provided by this invention has a unique microstructure. The center of the carbon-carbon composite material is a single carbon fiber, and the outer periphery of the single carbon fiber is surrounded by multiple concentric graphite sheets. Based on this special morphology, nano-metal particles can fill between any two adjacent graphite sheets, thereby ensuring that nano-metal particles are evenly distributed between any two graphite sheets. This ensures that the nano-metal particles are evenly distributed in the carbon-carbon composite material, thus ensuring that the carbon-carbon composite material has excellent corrosion resistance. At the same time, the presence of carbon and metal makes the carbon-carbon composite material have good electrical conductivity.

[0049] Specifically, the nano-metal particles contain copper, iron, aluminum, and optional group IVB metals. These nano-metal particles containing specific elements are filled between any two adjacent graphite sheets. By combining these specific metal elements, the corrosion resistance of the carbon-carbon composite material can be improved through synergistic effects.

[0050] In this invention, there are no specific limitations on the group IVB metal elements. Specifically, the group IVB metal elements can be titanium and / or zirconium.

[0051] In a preferred embodiment, in order to further improve the corrosion resistance of the carbon-carbon composite material, the group IVB metal element is titanium, that is, the nano-metal particles simultaneously contain copper, iron, aluminum and titanium.

[0052] To ensure that the carbon-carbon composite material has both excellent electrical conductivity and excellent corrosion resistance, the proportion of each element in the carbon-carbon composite material can be appropriately controlled.

[0053] In some embodiments, the carbon-carbon composite material contains 50-90% by weight of carbon, 1-15% by weight of copper, 0.5-10% by weight of iron, 0.1-5% by weight of aluminum, and 0-1% by weight of group IVB metals.

[0054] In a preferred embodiment, the carbon-carbon composite material preferably contains 60-70% by weight of carbon, 5-9% by weight of copper, 1-6% by weight of iron, 0.1-2.5% by weight of aluminum, and 0.05-0.5% by weight of group IVB metals.

[0055] In this invention, the presence of a large number of concentric graphite sheets surrounding the single carbon fiber allows for a more uniform distribution of the nano-metal particles among the graphite sheets, thereby improving the corrosion resistance of the carbon-carbon composite material. Conversely, a smaller number of concentric graphite sheets surrounding the single carbon fiber results in poor corrosion resistance of the carbon-carbon composite material. Preferably, the number of graphite sheets surrounding the single carbon fiber is 3-20 layers, more preferably 5-18 layers.

[0056] In this invention, the diameter of the single carbon fiber can be a conventional choice in the art. In some embodiments, the diameter of the single carbon fiber can be 4-8 μm, preferably 4.5-7.5 μm.

[0057] The length of the single carbon fiber is equivalent to the length of the carbon-carbon composite material; in some preferred embodiments, the length of the single carbon fiber can be 2-10 mm, preferably 3-9 mm.

[0058] The carbon-carbon composite material described in this invention has a unique microstructure. As can be seen from the scanning electron microscope, in the preferred case, the thickness of the multilayer graphite sheets gradually increases from the inside to the outside, which can improve the stability of the concentric circle structure of the carbon-carbon composite material.

[0059] The approximate volume ratio of carbon fiber and graphite in a carbon-carbon composite material can be inferred from the ratio of the total thickness of the graphite sheets to the diameter of a single carbon fiber. In a preferred embodiment, the ratio of the total thickness of the multilayer graphite sheets to the diameter of the single carbon fiber can be 1-100:1. Limiting the ratio of the total thickness of the graphite sheets to the diameter of the single carbon fiber within this range can improve the dimensional stability of the concentric structure of the carbon-carbon composite material, maintain the uniform dispersion and firm bonding between the layered graphite clusters, carbon fibers, and nano-metal particles, thereby improving the corrosion resistance of the carbon-carbon composite material.

[0060] In this invention, the appearance of the carbon-carbon composite material is not limited and can take on various forms. Specifically, the carbon-carbon composite material is generally straight or curved.

[0061] The carbon-carbon composite material provided by this invention further contains carbon particles that exist independently or in an aggregated state, wherein the presence of carbon particles can be observed on the surface of the carbon-carbon composite material. Preferably, the particle size of the carbon particles is 0.02-2.00 mm.

[0062] In this invention, the carbon-carbon composite material has a non-uniform diameter due to the presence of nano-metal particles. Specifically, at least a portion of the surface of the carbon-carbon composite material has a bamboo-like and / or protruding shape.

[0063] In some embodiments, the diameter of the carbon-carbon composite material can be 0.02-1 mm, preferably 0.1-0.3 mm; the length can be 0.1-10 mm, preferably 1-5 mm.

[0064] In this invention, specifically, based on Raman spectroscopy characterization, the ratio of the D peak intensity to the G peak intensity of the carbon-carbon composite material can be 0.07-0.3:1. When the ratio of the D peak intensity to the G peak intensity is within this range, the smaller the lattice defects of the carbon atoms, and the higher the electrical conductivity of the carbon-carbon composite material.

[0065] In this invention, specifically, in the Raman spectrum of the carbon-carbon composite material, the ratio of the peak intensity of the 2D peak to the G peak can be 0.2-1:1. When the ratio of the peak intensity of the 2D peak to the G peak is within this range, the carbon atoms have fewer lattice defects, the layered graphite flakes have a perfect and regular graphite structure, and the resulting carbon-carbon composite material has good electrical conductivity.

[0066] Furthermore, the carbon-carbon composite material described in this invention is gray or black.

[0067] The carbon-carbon composite material of the present invention also contains small amounts of other metallic elements, including zinc, manganese, silver, barium, lithium, magnesium, lead and strontium, with the content of each metallic element being less than 0.001 by weight.

[0068] In addition to the aforementioned elements, the carbon-carbon composite material of the present invention also contains elements such as oxygen, nitrogen, and sulfur, and the metal elements in the carbon-carbon composite material exist in the form of compounds.

[0069] A second aspect of the present invention provides a method for preparing a conductive and corrosion-resistant carbon-carbon composite material, the method comprising: reacting short-cut carbon fibers, a carbon source and a metal source at 1500-3500°C in the presence of an inert atmosphere, wherein the volumetric flow rate of the inert atmosphere is 20-1800 mL / min; wherein the metal source comprises a copper source, an iron source, an aluminum source and an optional group IVB metal source.

[0070] The method described in this invention is simple and easy to operate. It only requires mixing and contacting short-cut carbon fibers, a carbon source, and a specific non-carbon element source under specific conditions to carry out the reaction.

[0071] In the method described in this invention, if the reaction temperature is too low, concentric graphite sheets cannot be formed on the outside of a single carbon fiber, resulting in the inability of nano-metal particles to adhere to the graphite sheet surface in large quantities and uniformly, thus leading to poor corrosion resistance of the resulting material. If the reaction temperature is too high, the growth rate of graphite sheets on the carbon fiber surface is much greater than the adhesion rate of nano-metal particles on the graphite sheet layer, resulting in uneven distribution of nano-metal particles on the graphite sheet, which also leads to poor corrosion resistance of the resulting material.

[0072] In some embodiments, the reaction temperature can be 1500°C, 1800°C, 2000°C, 2200°C, 2500°C, 2800°C, 3000°C, 3200°C, or 3500°C. In a preferred embodiment, the reaction temperature is 1500-2800°C.

[0073] In some embodiments, the reaction time can be 12-720 hours. In a preferred embodiment, the reaction time is 24-120 hours, for example, 24 hours, 48 ​​hours, 72 hours, 80 hours, 100 hours, or 120 hours.

[0074] To ensure that the short-cut carbon fibers, carbon source, and metal source can be used to prepare the aforementioned carbon-carbon composite material, the reaction needs to be carried out under an inert atmosphere. Specifically, the inert atmosphere is nitrogen and / or an inert gas; the purity of the nitrogen and inert gas is >99.9% by volume, and the oxygen content in the inert atmosphere is <50 ppm.

[0075] Without an inert atmosphere for protection during the reaction, it is impossible to obtain a carbon-carbon composite material comprising a single carbon fiber and multiple layers of graphite sheets surrounding the single carbon fiber, with nano-metal particles filling the spaces between any two adjacent graphite sheets. Furthermore, if the volumetric flow rate of the inert atmosphere is too high, it is impossible to maintain a stable microenvironment for the growth of the graphite sheets, and the nano-metal particles will be unable to adhere to the surface of the graphite sheets.

[0076] In some embodiments, the volumetric flow rate of the inert atmosphere is 20-1800 mL / min. In a preferred embodiment, the volumetric flow rate of the inert atmosphere is 50-500 mL / min, more preferably 100-300 mL / min.

[0077] In this invention, in order to obtain a carbon-carbon composite material with a suitable ratio of carbon to metal elements, a large number of graphite sheets surrounding the diameter of a single carbon fiber, and excellent electrical conductivity and corrosion resistance, the weight ratio of the chopped carbon fiber, the carbon source, and the metal source can be appropriately controlled.

[0078] In some embodiments, the weight ratio of the metal source, the carbon source, and the chopped carbon fibers is 20-100:30-200:1, preferably 30-70:50-150:1;

[0079] The weight ratio of the copper source, the iron source, the aluminum source, and the group IVB metal source is 10-100:5-10:1:0-50.

[0080] In this invention, the metal source serves to generate nano-metal particles and fill the spaces between graphite sheets. The IVB group metal source can be a conventional choice in the art; specifically, the IVB group metal source is a titanium source and / or a zirconium source.

[0081] In a preferred embodiment, the group IVB metal source is a titanium source, that is, the metal source simultaneously contains a copper source, an iron source, an aluminum source, and a titanium source.

[0082] In this invention, the copper source can be a conventional choice in the art, such as a copper salt, copper oxide, or copper hydroxide. Specifically, the copper source can be selected from one or more of CuSO4, CuO, CuCl2, and Cu(OH)2.

[0083] In this invention, the iron source can be a conventional choice in the art, such as an iron salt, iron oxide, or iron hydroxide. Specifically, the iron source can be selected from one or more of FeO, Fe2O3, Fe3O4, Fe(OH)2, Fe(OH)3, FeCl2, FeCl3, and FePO4.

[0084] In this invention, the aluminum source can be a conventional choice in the art, such as an aluminum salt, aluminum oxide, or aluminum hydroxide. Specifically, the aluminum source can be selected from one or more of Al2O3, AlCl3, Al2(SO4)3, Al(OH)3, and AlPO4.

[0085] In this invention, the titanium source can be a conventional choice in the art, and can be a titanium salt, titanium oxide, or titanium hydroxide. Specifically, the titanium source can be selected from one or more of TiF4, TiF3, TiCl4, TiSO4, and TiO2.

[0086] In the method described in this invention, the carbon source functions to form graphite sheets on the outer periphery of a single carbon fiber. The carbon source can be a conventional choice in the art; specifically, it can be a carbonized resin and / or graphite. Preferably, the carbonized resin is a resin-based carbide with a rich porous structure after high-temperature carbonization. Preferably, the graphite is amorphous graphite.

[0087] In this invention, the reaction can be carried out in a conventionally used high-temperature furnace. Specifically, isostatic graphite or highly oriented graphite is used as the heating element in the high-temperature furnace. Preferably, the high-temperature furnace is connected to a tail gas recovery system via a pipeline. A valve is installed on the pipeline connecting the high-temperature furnace and the tail gas recovery system. The inner diameter of the pipeline is between 5-20 mm. A filter screen is installed before the valve along the gas flow direction. The selection of the pipeline, filter screen, and valve meets the temperature resistance requirements.

[0088] In this invention, the single carbon fiber at the center of the carbon-carbon composite material is formed from chopped carbon fibers. In a specific embodiment, the length of the chopped carbon fibers is 0.1-10 mm, preferably 1-5 mm; the K content is 12-320 K, preferably 12-48 K; and the carbon content is 85-95%.

[0089] A third aspect of the present invention provides a conductive and corrosion-resistant carbon-carbon composite material prepared by the method described above.

[0090] Preferably, the carbon-carbon composite material comprises a single carbon fiber and multiple layers of graphite sheets surrounding the single carbon fiber, with nano-metal particles filling between any two adjacent layers of graphite sheets, wherein the nano-metal particles contain copper, iron, aluminum and optional group IVB metal elements.

[0091] The fourth aspect of the present invention provides the conductive and corrosion-resistant carbon-carbon composite material described above, or the application of the conductive and corrosion-resistant carbon-carbon composite material described above as a conductive and corrosion-resistant material.

[0092] The carbon-carbon composite material described in this invention can be further processed as a raw material. Processing methods include, but are not limited to, blending (extrusion or granulation), strip forming, grinding (pulverizing), and calcination. Material products manufactured using the above processing methods, whose constituent elements and their contents fall within the scope of the claims and description of this invention, are all within the protection scope of this invention. Furthermore, as long as the types and contents of the contained elements are within the scope defined by this invention, regardless of whether they are raw materials or finished products, and the shape of the material is not limited to fibrous form; and it is not limited by the material processing method, they are all within the protection scope of this invention.

[0093] The present invention will be described in detail below through examples, but the scope of protection of the present invention is not limited thereto. Unless otherwise specified, all reagents used in the following examples are commercially available products.

[0094] In the following examples and comparative examples, the carbonized resin powder is YKD-508 blood perfusion carbonized resin (carbon skeleton spherical porous adsorption resin) produced by Henan Yinkai New Material Co., Ltd.

[0095] The testing methods used in this invention include:

[0096] 1. The surface and cross-sectional morphology of the carbon-carbon composite materials prepared in the examples and comparative examples were observed using a ZEISS Merlin field emission scanning electron microscope. The test conditions included: accelerating voltage 20-30 kV and electron beam current 10 pA-40 / 100 / 300 nA.

[0097] 2. The elemental composition, distribution, and particle size of the carbon-carbon composite materials prepared in the examples and comparative examples were analyzed using an X-ray energy dispersive spectroscopy (EDS) instrument configured with a field emission scanning electron microscope (FESS) from ZEISS Merlin, Germany. The area scanning mode testing conditions included: accelerating voltage of 20–30 kV and an effective probe working area of ​​150 mm². 2 The elemental range is Be to U, and the detection limit is approximately 0.1 wt.%.

[0098] 3. Raman Imaging Analysis of Carbon-Carbon Composite Material Cross-Sections: A laser micro-Raman spectrometer (RENISHAW, in-Via Raman microscope, UK, 532nm line, helium-neon laser, laser radiation model: QONTOR) was used to observe the cross-sectional morphology of the carbon-carbon composite materials prepared in the examples and comparative examples, and Raman imaging analysis was performed on the cross-sectional morphology. This allows for high-sensitivity spectral analysis under high-resolution conditions. The specific method includes: directly breaking the carbon-carbon composite material, observing the morphology after the cross-section is exposed, and using Live Track™ technology for real-time focusing. During the test, each point is acquired under focused conditions, and the Z-axis coordinate of each point is recorded to form a surface height image. The Raman imaging results can be superimposed on the height image. The in-situ Raman imaging area is 70µm*70µm, with a step size of 1µm, and the Raman spectrum recording range is 400-3100cm². -1 The integration time for each spectrum is 100 s. The cross-sectional morphology of the fibrous composite material was observed under a 20x objective lens, and Raman spectra were acquired at a specific location within a 1 μm x 1 μm region. This spectrum has a range of 1350 cm⁻¹. -1 Nearby D peak, 1582cm -1 Nearby G peak, and 2699cm -1 Nearby 2D peaks; also using Raman imaging, observe the intensity distribution of the D peaks at different points.

[0099] 4. The types and contents of non-carbon elements in the carbon-carbon composite materials prepared in the examples and comparative examples were tested using inductively coupled plasma atomic emission spectrometry.

[0100] The main instruments and reagents are as follows:

[0101] (1) Varian 725-ES inductively coupled plasma atomic emission spectrometer;

[0102] (2) Haoyue HMF1600-40 box furnace;

[0103] (3) LabTech Digiblock ST36 electrothermal digester;

[0104] (4) Multi-element standard solution: 1000ug / mL (Steel Research Institute Nake Testing Technology Co., Ltd.); Praseodymium standard stock solution: 1000ug / mL (National Nonferrous Metals and Electronic Materials Analysis and Testing Center); Vanadium standard stock solution: 1000ug / mL (National Nonferrous Metals and Electronic Materials Analysis and Testing Center); The ultrapure water used in the experiment was prepared by the Genie Purist intelligent ultrapure water system (resistivity = 18.2MΩcm, 25℃); Hydrogen peroxide (30wt%), hydrochloric acid, nitric acid and hydrofluoric acid were all of superior purity; Sulfuric acid was of process ultrapure purity (Sinopharm Chemical Reagent Co., Ltd.); Liquid argon (Chart Cryogenic Engineering Systems (Changzhou) Co., Ltd.).

[0105] The instrument's operating conditions are as follows:

[0106] Instrument operating parameters: High-frequency power: 1100W; Plasma gas flow rate: 15L / min -1 Auxiliary gas flow rate: 1.5 L / min -1 Atomizing gas flow rate: 0.75L / min -1 Sample injection pump speed: 15 rpm; observation height: 10 mm.

[0107] The experimental method is as follows:

[0108] (1) Accurately weigh 0.1g of sample into a clean quartz crucible, place it in a box furnace, and gradually heat it to 930℃ for ashing treatment to obtain ash. The percentage of weight loss of the sample during the calcination process is the carbon content of the fibrous carbon-carbon composite material in this patent;

[0109] (2) Use a small amount of ultrapure water to transfer all the ash to a PFA test tube, add aqua regia, hydrogen peroxide, sulfuric acid and hydrofluoric acid in sequence, cover and place in an electric digestion apparatus to heat until the sample is completely digested;

[0110] (3) Remove the test tube and cool it to room temperature. Transfer it to a 50 mL volumetric flask using ultrapure water and make up to volume for testing.

[0111] (4) Prepare mixed standard solutions of elements, plot test spectra, use inductively coupled plasma atomic emission spectrometer to detect the test solution, and calculate the content of each element according to the plotted test spectra.

[0112] Example 1

[0113] Methods for preparing carbon-carbon composite materials include:

[0114] Short-cut carbon fibers (12K, 3mm in length, 90% carbon by weight), carbonized resin powder, and a metal source were reacted in a high-temperature furnace for 48 hours in the presence of nitrogen.

[0115] The weight ratio of metal source, carbonized resin powder, and chopped carbon fiber is 30:80:1, and the weight ratio of metal source CuO, Fe2O3, Al2O3, and TiF4 is 20:8:1:15.

[0116] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2200℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 100mL / min.

[0117] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0118] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0119] (1) As Figure 7 As shown, the center consists of a single carbon fiber with a diameter of 5 μm and a length of 3 mm. The outer periphery of the single carbon fiber is surrounded by 10 layers of concentric graphite sheets, with the thickness of the 10 graphite sheets gradually increasing from the inside out. The ratio of the total thickness of the 10 graphite sheets to the diameter of the single carbon fiber is 9:1. Nanoscale metal particles are filled between any two adjacent graphite sheets. The carbon-carbon composite material has a diameter of 0.1 mm and a length of 3 mm.

[0120] (2) The carbon-carbon composite material is gray, and carbon particles with a particle size of 0.05 mm are present on the surface of the carbon-carbon composite material. The carbon-carbon composite material is curved in the axial direction, and some surfaces are bamboo-like and protruding (e.g. Figure 1 , Figure 6 (As shown); In the Raman imaging spectrum of carbon-carbon composite materials, the average ratio of the peak intensity of D peak to G peak is 0.158:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.477:1.

[0121] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 60% by weight; copper content of 8.5% by weight; iron content of 5.5% by weight; aluminum content of 2.5% by weight; and titanium content of 0.5% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0122] The features of steps (1) and (2) were obtained by analysis using a ZEISS Merlin field emission scanning electron microscope and an X-ray energy dispersive spectrometer configured with a ZEISS Merlin field emission scanning electron microscope.

[0123] from Figures 2-5 As can be seen from the elemental energy spectrum, the composite material prepared in this embodiment contains copper ( Figure 2 ),iron( Figure 3 ),aluminum( Figure 4 ),titanium( Figure 5 It is uniformly distributed and consists of nanoparticles.

[0124] Example 2

[0125] Methods for preparing carbon-carbon composite materials include:

[0126] Short-cut carbon fibers (24K grade, 6mm in length, 95% carbon by weight), amorphous graphite, and a metal source were reacted in a high-temperature furnace for 150 hours in the presence of nitrogen.

[0127] The weight ratio of the metal source, amorphous graphite, and chopped carbon fibers is 90:190:1, and the weight ratio of the metal sources CuCl2, Fe3O4, Al(OH)3, and TiO2 is 18:5:1:12.

[0128] The high-temperature furnace uses highly oriented graphite as the heating element, with a core temperature of 3000℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 350mL / min.

[0129] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 5mm, and a filter screen is installed before the valve along the gas flow direction.

[0130] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0131] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 6 mm; the outer periphery of the single carbon fiber is surrounded by 8 layers of concentric graphite sheets, the thickness of the 8 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 8 graphite sheets to the diameter of the single carbon fiber is 48:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.5 mm and a length of 6 mm.

[0132] (2) The carbon-carbon composite material is black, and each graphite sheet has carbon particles in aggregate form distributed on its surface. The particle size of the carbon particles is 1.5 mm. The carbon-carbon composite material is linear in the axial direction, and some of its surfaces have blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of the D peak to the G peak is 0.160:1, and the average ratio of the peak intensity of the 2D peak to the G peak is 0.483:1.

[0133] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 71 wt%; copper content of 9.5 wt%; iron content of 6.8 wt%; aluminum content of 3.3 wt%; and titanium content of 0.7 wt%. Elements with a content of less than 0.001 wt% include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0134] Example 3

[0135] Methods for preparing carbon-carbon composite materials include:

[0136] Short-cut carbon fibers (50K specification, 9mm length, 90% carbon content), amorphous graphite, and a metal source were reacted in a high-temperature furnace for 80 hours in the presence of nitrogen.

[0137] The weight ratio of the metal source, amorphous graphite, and chopped carbon fibers is 60:100:1, and the weight ratio of the metal sources CuO, Fe2O3, Al2O3, and TiF4 is 35:10:1:30.

[0138] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2800℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 400mL / min.

[0139] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 15mm, and a filter screen is installed before the valve along the gas flow direction.

[0140] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0141] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 9 mm; the outer periphery of the single carbon fiber is surrounded by 6 layers of concentric graphite sheets, the thickness of the 6 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 6 graphite sheets to the diameter of the single carbon fiber is 30:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.3 mm and a length of 9 mm.

[0142] (2) The carbon-carbon composite material is gray. There are carbon particles on the surface of the carbon-carbon composite material with a particle size of 0.09 mm. The carbon-carbon composite material is linear in the axial direction, and some of the surface is bamboo-like. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.180, and the average ratio of the peak intensity of 2D peak to G peak is 0.549:1.

[0143] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 61% by weight; copper content of 8.9% by weight; iron content of 7.7% by weight; aluminum content of 4.1% by weight; and titanium content of 0.3% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0144] Example 4

[0145] Methods for preparing carbon-carbon composite materials include:

[0146] Short-cut carbon fibers (12K specification, 6mm length, 95% carbon content by weight), amorphous graphite, and a metal source were reacted in a high-temperature furnace for 150 hours in the presence of nitrogen.

[0147] The weight ratio of the metal source, amorphous graphite, and chopped carbon fibers is 40:120:1, and the weight ratio of the metal sources CuCl2, Fe3O4, Al(OH)3, and TiO2 is 15:5:1:10.

[0148] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2800℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 500mL / min.

[0149] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 20mm, and a filter screen is installed before the valve along the gas flow direction.

[0150] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0151] (1) The center is a single carbon fiber with a diameter of 7 μm and a length of 6 mm; the outer periphery of the single carbon fiber is surrounded by 15 layers of concentric graphite sheets, the thickness of the 15 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 15 graphite sheets to the diameter of the single carbon fiber is 65:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.7 mm and a length of 6 mm.

[0152] (2) The carbon-carbon composite material is black, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 1.2 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surface is covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.177:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.550:1.

[0153] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 67 wt%; copper content of 7.3 wt%; iron content of 4.2 wt%; aluminum content of 2.8 wt%; and titanium content of 0.6 wt%. Elements with a content of less than 0.001 wt% include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0154] Example 5

[0155] Methods for preparing carbon-carbon composite materials include:

[0156] Short-cut carbon fibers (12K specification, 9mm length, 95% carbon content), amorphous graphite, and a metal source were reacted in a high-temperature furnace for 36 hours in the presence of nitrogen.

[0157] The weight ratio of the metal source, amorphous graphite, and chopped carbon fibers is 20:50:1, and the weight ratio of the metal sources CuCl2, Fe3O4, Al(OH)3, and TiO2 is 10:5:1:10.

[0158] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2800℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 50mL / min.

[0159] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 20mm, and a filter screen is installed before the valve along the gas flow direction.

[0160] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0161] (1) The center is a single carbon fiber with a diameter of 7 μm and a length of 9 mm; the outer periphery of the single carbon fiber is surrounded by 16 layers of concentric graphite sheets, the thickness of the 16 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 16 graphite sheets to the diameter of the single carbon fiber is 58:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.8 mm and a length of 9 mm.

[0162] (2) The carbon-carbon composite material is black, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 1.3 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are bamboo-like and protruding. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.186:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.555:1.

[0163] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 69 wt%; copper content of 7.5 wt%; iron content of 4.9 wt%; aluminum content of 2.5 wt%; and titanium content of 0.8 wt%. Elements with a content of less than 0.001 wt% include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0164] Example 6

[0165] Methods for preparing carbon-carbon composite materials include:

[0166] Short-cut carbon fibers (12K specification, 6mm length, 95% carbon content), amorphous graphite, and a metal source were reacted in a high-temperature furnace for 120 hours in the presence of nitrogen.

[0167] The weight ratio of the metal source, amorphous graphite, and chopped carbon fibers is 30:80:1, and the weight ratio of the metal sources CuCl2, Fe3O4, Al(OH)3, and TiO2 is 25:5:1:20.

[0168] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2800℃, nitrogen purity of 99.99% by volume, oxygen concentration of 20ppm, and a gas flow rate of 100mL / min.

[0169] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0170] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0171] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 6 mm; the outer periphery of the single carbon fiber is surrounded by 18 layers of concentric graphite sheets, the thickness of the 18 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 18 graphite sheets to the diameter of the single carbon fiber is 100:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 1.0 mm and a length of 6 mm.

[0172] (2) The carbon-carbon composite material is black, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 1.5 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.183:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.551:1.

[0173] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 66 wt%; copper content of 7.2 wt%; iron content of 4.4 wt%; aluminum content of 2.2 wt%; and titanium content of 0.5 wt%. Elements with a content of less than 0.001 wt% include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0174] Example 7

[0175] Methods for preparing carbon-carbon composite materials include:

[0176] Short-cut carbon fibers (12K specification, 6mm length, 95% carbon content), amorphous graphite, and a metal source were reacted in a high-temperature furnace for 144 hours in the presence of nitrogen.

[0177] The weight ratio of the metal source, amorphous graphite, and chopped carbon fibers is 40:100:1, and the weight ratio of the metal sources CuCl2, Fe3O4, Al(OH)3, and TiO2 is 15:5:1:10.

[0178] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2800℃, nitrogen purity of 99.99% by volume, oxygen concentration of 20ppm, and a gas flow rate of 200mL / min.

[0179] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0180] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0181] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 6 mm; the outer periphery of the single carbon fiber is surrounded by 12 layers of concentric graphite sheets, the thickness of the 12 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 12 graphite sheets to the diameter of the single carbon fiber is 41:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.4 mm and a length of 5 mm.

[0182] (2) The carbon-carbon composite material is black, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 0.6 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.184:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.552:1.

[0183] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 65% by weight; copper content of 7.1% by weight; iron content of 4.1% by weight; aluminum content of 2.6% by weight; and titanium content of 0.5% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0184] Example 8

[0185] Methods for preparing carbon-carbon composite materials include:

[0186] Short-cut carbon fibers (12K specification, 6mm length, 95% carbon content), amorphous graphite, and a metal source were reacted in a high-temperature furnace for 72 hours in the presence of nitrogen.

[0187] The weight ratio of the metal source, amorphous graphite, and chopped carbon fibers is 70:120:1, and the weight ratio of the metal sources CuCl2, Fe3O4, Al(OH)3, and TiO2 is 40:12:1:20.

[0188] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2800℃, nitrogen purity of 99.99% by volume, oxygen concentration of 20ppm, and a gas flow rate of 300mL / min.

[0189] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0190] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0191] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 6 mm; the outer periphery of the single carbon fiber is surrounded by 13 layers of concentric graphite sheets, the thickness of the 13 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 13 graphite sheets to the diameter of the single carbon fiber is 49:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.5 mm and a length of 6 mm.

[0192] (2) The carbon-carbon composite material is black, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 1 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.179:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.549:1.

[0193] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 65% by weight; copper content of 7.2% by weight; iron content of 4.4% by weight; aluminum content of 2.3% by weight; and titanium content of 0.2% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0194] Example 9

[0195] Methods for preparing carbon-carbon composite materials include:

[0196] Short-cut carbon fibers (12K specification, 6mm length, 95% carbon content), amorphous graphite, and a metal source were reacted in a high-temperature furnace for 48 hours in the presence of nitrogen.

[0197] The weight ratio of the metal source, amorphous graphite, and chopped carbon fibers is 80:110:1, and the weight ratio of the metal sources CuCl2, Fe3O4, Al(OH)3, and TiO2 is 10:10:1:10.

[0198] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2800℃, nitrogen purity of 99.99% by volume, oxygen concentration of 20ppm, and a gas flow rate of 500mL / min.

[0199] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0200] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0201] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 6 mm; the outer periphery of the single carbon fiber is surrounded by 16 layers of concentric graphite sheets, the thickness of the 16 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 16 graphite sheets to the diameter of the single carbon fiber is 90:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.9 mm and a length of 6 mm.

[0202] (2) The carbon-carbon composite material is black, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 1.2 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the ratio of the peak intensity of D peak to G peak is 0.179:1, and the ratio of the peak intensity of 2D peak to G peak is 0.553:1.

[0203] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 68 wt%; copper content of 6.8 wt%; iron content of 4.9 wt%; aluminum content of 2.8 wt%; and titanium content of 1.2 wt%. Elements with a content of less than 0.001 wt% include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0204] Example 10

[0205] The method was implemented according to Example 1, except that the titanium source TiF4 was not added.

[0206] Methods for preparing carbon-carbon composite materials include:

[0207] Short-cut carbon fibers (12K, 3mm in length, 90% carbon by weight), carbonized resin powder, and a metal source were reacted in a high-temperature furnace for 48 hours in the presence of nitrogen.

[0208] The weight ratio of the metal source, carbonized resin powder, and chopped carbon fibers is 30:80:1, and the weight ratio of the metal sources CuO, Fe2O3, and Al2O3 is 20:8:1.

[0209] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2200℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 100mL / min.

[0210] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0211] The carbon-carbon composite material prepared in this embodiment has the following characteristics:

[0212] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 3 mm; the outer periphery of the single carbon fiber is surrounded by 10 layers of concentric graphite sheets, the thickness of the 10 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 10 graphite sheets to the diameter of the single carbon fiber is 8:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.09 mm and a length of 3 mm.

[0213] (2) The carbon-carbon composite material is gray. There are carbon particles on the surface of the carbon-carbon composite material with a particle size of 0.05 mm. The carbon-carbon composite material is curved in the axial direction and has blocky protrusions distributed on some surfaces. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.156:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.475:1.

[0214] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 60% by weight; copper content of 8.5% by weight; iron content of 5.5% by weight; and aluminum content of 3% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0215] Comparative Example 1

[0216] The method was implemented according to Example 1, except that short-cut carbon fibers were not added into the high-temperature furnace.

[0217] Because this comparative example lacks short-cut carbon fibers, the metal particles cannot form growth attachment points, and the carbon vapor can only grow into blocky carbon-containing materials with extremely high carbon content on the surface of the inner wall of the high-temperature furnace, thus failing to obtain the carbon-carbon composite material described in this invention.

[0218] The material obtained in this comparative example is a blocky product formed from a carbon source. The material contains 99.9% by weight of carbon and does not contain Cu, Fe, Al, or Ti.

[0219] Comparative Example 2

[0220] The method of Example 1 was followed, except that the reaction process was not protected by an inert atmosphere.

[0221] Without an inert atmosphere for protection, the carbonized resin powder oxidizes into carbon dioxide, and the short-cut carbon fibers with higher temperature resistance break into short-cut carbon fibers with uneven shapes and oxidized and etched surfaces. It is impossible to form a concentric circle structure with multiple layers of graphite sheets surrounding a single carbon fiber, nor can it fill with nano-metal particles. Therefore, the carbon-carbon composite material described in this invention cannot be obtained.

[0222] The material prepared in this comparative example contains 99.9% by weight of carbon and does not contain Cu, Fe, Al, or Ti.

[0223] Comparative Example 3

[0224] The method was implemented according to Example 1, except that no carbonized resin powder and metal source were added to the high-temperature furnace.

[0225] The material obtained in this comparative example is a product formed from short-cut carbon fibers. The material contains 99.9% by weight of carbon and does not contain Cu, Fe, Al, or Ti. Therefore, it does not yield the carbon-carbon composite material described in this invention.

[0226] Comparative Example 4

[0227] The method was implemented according to Example 1, except that the center temperature was 1200°C.

[0228] In this comparative example, the temperature was too low, which prevented the carbon in the carbonized resin powder from growing further on the surface of a single carbon fiber. At the same time, the metal particles could not adhere to the surface of the carbon fiber or graphite sheet, thus failing to obtain the carbon-carbon composite material described in this invention.

[0229] The material prepared in this comparative example is a mixture formed by the independent reaction of short-cut carbon fibers, carbonized resin powder, and metal source.

[0230] Comparative Example 5

[0231] The method was carried out according to Example 1, except that the gas flow rate was 2000 mL / min.

[0232] In this comparative example, due to the excessive gas flow rate, the microenvironment for stable growth of graphite sheets could not be maintained, and metal particles could not adhere to the surface of carbon fibers or graphite sheets, thus failing to obtain the carbon-carbon composite material described in this invention.

[0233] The material prepared in this comparative example is a mixture formed by the independent reaction of short-cut carbon fibers, carbonized resin powder, and metal source.

[0234] Comparative Example 6

[0235] The method was implemented according to Example 1, except that the metal sources CuO, Fe2O3, Al2O3 and TiF4 were not added to the high-temperature furnace.

[0236] The carbon-carbon composite material prepared in this comparative example has the following characteristics:

[0237] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 3 mm; the outer periphery of the single carbon fiber is surrounded by 10 layers of concentric graphite sheets, the thickness of the 10 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 10 graphite sheets to the diameter of the single carbon fiber is 10:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.1 mm and a length of 3 mm.

[0238] (2) The carbon-carbon composite material is gray. Carbon particles are present on the surface of the carbon-carbon composite material, and the particle size of the carbon particles is 0.05 mm. The carbon-carbon composite material is curved in the axial direction, and blocky protrusions are distributed on some surfaces. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.182:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.545:1.

[0239] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 99.9% by weight; elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead and strontium.

[0240] Comparative Example 7

[0241] The method of Example 1 was implemented, except that Fe2O3 was replaced with Co2O3.

[0242] The carbon-carbon composite material prepared in this comparative example has the following characteristics:

[0243] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 3 mm; the outer periphery of the single carbon fiber is surrounded by 10 layers of concentric graphite sheets, the thickness of the 10 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 10 graphite sheets to the diameter of the single carbon fiber is 9:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.1 mm and a length of 3 mm.

[0244] (2) The carbon-carbon composite material is gray. There are carbon particles on the surface of the carbon-carbon composite material with a particle size of 0.05 mm. The carbon-carbon composite material is curved in the axial direction and has blocky protrusions distributed on some surfaces. In the Raman imaging spectrum of the carbon-carbon composite material, the ratio of the peak intensity of D peak to G peak is 0.158:1, and the average value of the ratio of the peak intensity of 2D peak to G peak is 0.477.

[0245] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 60% by weight; copper content of 8.5% by weight; cobalt content of 7.9% by weight; aluminum content of 3% by weight; and titanium content of 0.5% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0246] Comparative Example 8

[0247] The method of Example 1 was implemented, except that CuO was replaced with ZnO.

[0248] The carbon-carbon composite material prepared in this comparative example has the following characteristics:

[0249] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 3 mm; the outer periphery of the single carbon fiber is surrounded by 10 layers of concentric graphite sheets, the thickness of the 10 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 10 graphite sheets to the diameter of the single carbon fiber is 9:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.1 mm and a length of 3 mm.

[0250] (2) The carbon-carbon composite material is gray, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 0.05 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the ratio of the peak intensity of D peak to G peak is 0.158:1, and the ratio of the peak intensity of 2D peak to G peak is 0.477:1.

[0251] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 60% by weight; zinc content of 4.8% by weight; iron content of 5.5% by weight; aluminum content of 3% by weight; and titanium content of 0.5% by weight. Elements with a content of less than 0.001% by weight include: copper, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0252] Comparative Example 9

[0253] The method of Example 1 was implemented, except that no aluminum source was added, i.e., the metal source was CuO, Fe2O3 and TiF4.

[0254] Methods for preparing carbon-carbon composite materials include:

[0255] Short-cut carbon fibers (12K, 3mm in length, 90% carbon by weight), carbonized resin powder, and a metal source were reacted in a high-temperature furnace for 48 hours in the presence of nitrogen.

[0256] The weight ratio of the metal source, carbonized resin powder, and chopped carbon fibers is 30:80:1, and the weight ratio of the metal sources CuO, Fe2O3, and TiF4 is 21:8:15.

[0257] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2200℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 100mL / min.

[0258] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0259] The carbon-carbon composite material prepared in this comparative example has the following characteristics:

[0260] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 3 mm; the outer periphery of the single carbon fiber is surrounded by 10 layers of concentric graphite sheets, the thickness of the 10 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 10 graphite sheets to the diameter of the single carbon fiber is 11:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.1 mm and a length of 3 mm.

[0261] (2) The carbon-carbon composite material is gray, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 0.05 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.182:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.553:1.

[0262] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 60% by weight; copper content of 8.5% by weight; iron content of 5.5% by weight; and titanium content of 0.5% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0263] Comparative Example 10

[0264] The method of Example 1 was implemented, except that no iron source was added, i.e., the metal source was CuO, Al2O3 and TiF4.

[0265] Methods for preparing carbon-carbon composite materials include:

[0266] Short-cut carbon fibers (12K specification, 3mm length, 90% carbon content by weight), carbonized resin powder, and a metal source were reacted in a high-temperature furnace for 48 hours in the presence of nitrogen.

[0267] The weight ratio of chopped carbon fibers, carbonized resin powder, and metal source is 30:80:1, and the weight ratio of CuO, Al2O3, and TiF4 metal sources is 28:1:15.

[0268] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a center temperature of 2200℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 100mL / min.

[0269] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0270] The carbon-carbon composite material prepared in this comparative example has the following characteristics:

[0271] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 3 mm; the outer periphery of the single carbon fiber is surrounded by 10 layers of concentric graphite sheets, the thickness of the 10 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 10 graphite sheets to the diameter of the single carbon fiber is 10:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.1 mm and a length of 3 mm.

[0272] (2) The carbon-carbon composite material is gray, and there are carbon particles on the surface of the carbon-carbon composite material with a particle size of 0.05 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.185:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.545:1.

[0273] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 60% by weight; copper content of 8.5% by weight; aluminum content of 3% by weight; and titanium content of 0.5% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0274] Comparative Example 11

[0275] The method of Example 1 was implemented, except that no copper source was added, i.e., the metal source was Fe2O3, Al2O3 and TiF4.

[0276] Methods for preparing carbon-carbon composite materials include:

[0277] Short-cut carbon fibers (12K, 3mm in length, 90% carbon by weight), carbonized resin powder, and a metal source were reacted in a high-temperature furnace for 48 hours in the presence of nitrogen.

[0278] The weight ratio of the metal source, carbonized resin powder, and chopped carbon fibers is 30:80:1, and the weight ratio of the metal sources Fe2O3, Al2O3, and TiF4 is 28:1:15.

[0279] The high-temperature furnace uses isostatically pressed graphite as the heating element, with a core temperature of 2200℃, nitrogen purity of 99.99% by volume, oxygen concentration of 40ppm, and a gas flow rate of 100mL / min.

[0280] A valve is installed on the pipe connecting the high-temperature furnace and the exhaust gas recovery system. The valve is fully open, the pipe has an inner diameter of 10mm, and a filter screen is installed before the valve along the gas flow direction.

[0281] The carbon-carbon composite material prepared in this comparative example has the following characteristics:

[0282] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 3 mm; the outer periphery of the single carbon fiber is surrounded by 10 layers of concentric graphite sheets, the thickness of the 10 graphite sheets gradually increases from the inside to the outside, and the ratio of the total thickness of the 10 graphite sheets to the diameter of the single carbon fiber is 9:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.1 mm and a length of 3 mm.

[0283] (2) The carbon-carbon composite material is gray. Carbon particles are present on the surface of the carbon-carbon composite material, and the particle size of the carbon particles is 0.05 mm. The carbon-carbon composite material is curved in the axial direction, and some of the surfaces are covered with blocky protrusions. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.180:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.549:1.

[0284] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 60% by weight; iron content of 5.5% by weight; aluminum content of 3% by weight; and titanium content of 0.5% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0285] Comparative Example 12

[0286] The method was carried out according to Example 1, except that the gas flow rate was 10 mL / min.

[0287] The carbon-carbon composite material prepared in this comparative example has the following characteristics:

[0288] (1) The center is a single carbon fiber with a diameter of 5 μm and a length of 3 mm; the outer periphery of the single carbon fiber is surrounded by two concentric graphite sheets with the thickness of the two graphite sheets gradually increasing from the inside to the outside, and the ratio of the total thickness of the two graphite sheets to the diameter of the single carbon fiber is 1.1:1; nano-metal particles are filled between any two adjacent graphite sheets; the carbon-carbon composite material has a diameter of 0.015 mm and a length of 3 mm.

[0289] (2) The carbon-carbon composite material is gray. Carbon particles are present on the surface of the carbon-carbon composite material, and the particle size of the carbon particles is 0.01 mm. The carbon-carbon composite material is curved in the axial direction, and blocky protrusions are distributed on some surfaces. In the Raman imaging spectrum of the carbon-carbon composite material, the average ratio of the peak intensity of D peak to G peak is 0.177:1, and the average ratio of the peak intensity of 2D peak to G peak is 0.530:1.

[0290] (3) The main elements contained in carbon-carbon composite materials include: carbon content of 95% by weight; copper content of 0.6% by weight; iron content of 0.1% by weight; aluminum content of 0.2% by weight; and titanium content of 0.05% by weight. Elements with a content of less than 0.001% by weight include: zinc, manganese, silver, barium, lithium, magnesium, lead, and strontium.

[0291] Test case

[0292] The resistivity of the materials prepared in the examples and comparative examples was tested according to the national standard GB / T24525-2009 "Method for Determination of Resistivity of Carbon Materials". The results are shown in Table 1. The resistivity is low and the conductivity is good.

[0293] The corrosion resistance of the materials prepared in the examples and comparative examples was tested as follows: The materials were placed in a 100% by mass mixed solution of hydrofluoric acid and nitric acid (the weight ratio of hydrofluoric acid to nitric acid was 1:2) for testing. After corrosion for 300 hours, the corrosion rate (c%) of the materials was calculated. The corrosion rate is the ratio of the mass difference of the materials before and after corrosion to the mass of the materials before corrosion. The results are shown in Table 1. The smaller the corrosion rate, the better the corrosion resistance.

[0294] Table 1

[0295]

[0296]

[0297] As can be seen from Table 1, the resistivity and corrosion rate of the materials in the examples are significantly lower than those in the comparative examples. This shows that the carbon-carbon composite material prepared by the technical solution described in this invention has excellent electrical conductivity and corrosion resistance.

[0298] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A conductive and corrosion-resistant carbon-carbon composite material, characterized in that, The carbon-carbon composite material includes a single carbon fiber and multiple layers of graphite sheets surrounding the single carbon fiber. Nanoscale metal particles are filled between any two adjacent layers of graphite sheets, wherein the nanoscale metal particles contain copper, iron, aluminum and group IVB metals. The carbon-carbon composite material contains 50-90% by weight of carbon, 1-15% by weight of copper, 0.5-10% by weight of iron, 0.1-5% by weight of aluminum, and 0-1% by weight of group IVB metals.

2. The carbon-carbon composite material according to claim 1, characterized in that, The carbon-carbon composite material contains 60-70% by weight of carbon, 5-9% by weight of copper, 1-6% by weight of iron, 0.1-2.5% by weight of aluminum, and 0.05-0.5% by weight of group IVB metals.

3. The carbon-carbon composite material according to claim 1 or 2, characterized in that, The group IVB metal elements are titanium and / or zirconium.

4. The carbon-carbon composite material according to claim 1, characterized in that, The nano-metal particles contain copper, iron, aluminum and titanium.

5. The carbon-carbon composite material according to claim 1, characterized in that, The number of graphite sheets surrounding the outer periphery of the single carbon fiber is 3-20 layers.

6. The carbon-carbon composite material according to claim 5, characterized in that, The number of graphite sheets surrounding the outer periphery of the single carbon fiber is 5-18 layers.

7. The carbon-carbon composite material according to claim 1, characterized in that, The diameter of a single carbon fiber is 4-8 μm; the length is 2-10 mm.

8. The carbon-carbon composite material according to claim 7, characterized in that, The diameter of a single carbon fiber is 4.5-7.5 μm.

9. The carbon-carbon composite material according to claim 7, characterized in that, The length of a single carbon fiber is 3-9 mm.

10. The carbon-carbon composite material according to claim 1, characterized in that, The thickness of the multi-layered graphite sheet gradually increases from the inside to the outside.

11. The carbon-carbon composite material according to claim 1, characterized in that, The ratio of the total thickness of the multilayer graphite sheets to the diameter of the single carbon fiber is 1-100:

1.

12. The carbon-carbon composite material according to claim 1, characterized in that, The carbon-carbon composite material is either straight or curved.

13. The carbon-carbon composite material according to claim 1, characterized in that, At least a portion of the surface of the carbon-carbon composite material is bamboo-like and / or raised.

14. The carbon-carbon composite material according to claim 1, characterized in that, The carbon-carbon composite material has a diameter of 0.02-1 mm and a length of 0.1-10 mm.

15. The carbon-carbon composite material according to claim 14, characterized in that, The diameter of the carbon-carbon composite material is 0.1-0.3 mm.

16. The carbon-carbon composite material according to claim 14, characterized in that, The length of the carbon-carbon composite material is 1-5 mm.

17. The carbon-carbon composite material according to claim 1, characterized in that, In the Raman spectrum of the carbon-carbon composite material, the ratio of the peak intensity of the D peak to the G peak is 0.07-0.3:

1.

18. The carbon-carbon composite material according to claim 1, characterized in that, In the Raman spectrum of the carbon-carbon composite material, the ratio of the peak intensity of the 2D peak to the G peak is 0.2-1:

1.

19. A method for preparing the conductive and corrosion-resistant carbon-carbon composite material according to any one of claims 1-18, characterized in that, The method includes: reacting short-cut carbon fibers, a carbon source, and a metal source at 1500-3500℃ in the presence of an inert atmosphere, wherein the volumetric flow rate of the inert atmosphere is 20-1800 mL / min. The metal source includes copper, iron, aluminum and IVB group metal sources.

20. The method according to claim 19, characterized in that, The weight ratio of the metal source, the carbon source, and the chopped carbon fibers is 20-100:30-200:1; The weight ratio of the copper source, the iron source, the aluminum source, and the group IVB metal source is 10-100:5-10:1:0-50.

21. The method according to claim 20, characterized in that, The weight ratio of the metal source, the carbon source, and the chopped carbon fibers is 30-70:50-150:

1.

22. The method according to claim 19 or 20, characterized in that, The group IVB metal source is a titanium source and / or a zirconium source.

23. The method according to claim 19, characterized in that, The metal source includes copper, iron, aluminum and titanium.

24. The method according to claim 23, characterized in that, The copper source is selected from one or more of CuSO4, CuO, CuCl2 and Cu(OH)2.

25. The method according to claim 23, characterized in that, The iron source is selected from one or more of FeO, Fe2O3, Fe3O4, Fe(OH)2, Fe(OH)3, FeCl2, FeCl3 and FePO4.

26. The method according to claim 23, characterized in that, The aluminum source is selected from one or more of Al2O3, AlCl3, Al2(SO4)3, Al(OH)3 and AlPO4.

27. The method according to claim 23, characterized in that, The titanium source is selected from one or more of TiF4, TiF3, TiCl4, TiSO4 and TiO2.

28. The method according to claim 19, characterized in that, The carbon source is carbonized resin and / or graphite.

29. The method according to claim 28, characterized in that, The graphite is amorphous graphite.

30. The method according to claim 19, characterized in that, The reaction temperature is 1500-2800℃; the reaction time is 12-720 hours; and the volumetric flow rate of the inert atmosphere is 50-500 mL / min.

31. The method according to claim 30, characterized in that, The reaction time is 24-120 hours.

32. The method according to claim 30, characterized in that, The volumetric flow rate of the inert atmosphere is 100-300 mL / min.

33. The method according to claim 19, characterized in that, The chopped carbon fibers have a length of 0.1-10 mm, a specification of 12-320 K, and a carbon content of 85-95% by weight.

34. The method according to claim 33, characterized in that, The length of the chopped carbon fiber is 1-5 mm.

35. The method according to claim 33, characterized in that, The chopped carbon fiber has a specification of 12-48K.

36. The use of the conductive and corrosion-resistant carbon-carbon composite material according to any one of claims 1-18 as a conductive and corrosion-resistant material.

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