A carbonaceous material with a coating and a method for producing the same

Abstract

The application discloses a kind of carbonaceous material with coating and its preparation method, material is made by following method: (1) form microstructure groove on the surface of matrix, and prepare metal catalyst layer;(2) using silicon-containing slurry is impregnated to matrix;(3) carbonaceous material matrix is heated to grow and form silicon carbide nanowire connecting layer, obtain intermediate product A;(4) on intermediate product A deposition form silicon carbide nanowire reinforced silicon carbide layer, obtain intermediate product B;(5) on intermediate product B deposition preparation silicon carbide-zirconium carbide composite layer, post-processing obtains intermediate product C;(6) on intermediate product C deposition preparation zirconium carbide layer.The application avoids the problem of single coating in prior art, ensures the transition and bonding strength between coating and matrix, promotes coating and matrix to present three-dimensional interpenetration mechanical cooperation structure, effectively improves the interface bonding strength of coating and matrix by mechanical connection and interface constraint.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology for carbonaceous materials, and specifically to a coated carbonaceous material and its preparation method. Background Technology

[0002] Graphite possesses excellent electrical and thermal conductivity; its porosity gives it a low coefficient of thermal expansion and excellent thermal shock resistance; furthermore, its low temperature coefficient of resistance and low thermal inertia allow for rapid heating and cooling with minimal heat loss. Graphite is commonly used in specialized industrial furnaces as heating elements, insulation cylinders, flow guides, and crucibles. However, with the comprehensive development of the semiconductor industry, when graphite is chosen as a heating element, insulation cylinder, flow guide, or crucible for refining single-crystal silicon, indium phosphate, indium phosphide, and wafer growth furnaces, its inherent shortcomings prevent it from meeting the demands of high-purity material refining. Firstly, when used as a heating element in certain furnace types, the temperature difference between the hot and cold ends can cause cracks at the interface. Secondly, due to the special sealed structure of vacuum furnaces, damaged graphite resistance heating elements cannot be replaced at high temperatures, forcing the furnace to continue operating with incomplete heating elements, thus compromising heating efficiency and internal temperature. Secondly, graphite materials have low strength and high brittleness, making them difficult to process and transport. In the refining process of high-capacity semiconductor materials, graphite crucibles cannot withstand the load, severely impacting the progress of advanced mass production. Furthermore, at high temperatures, carbon atoms in graphite continuously volatilize, leading to two negative consequences: first, carbon atoms diffuse into the wafer, causing a decrease in wafer quality; second, numerous corrosion pits form on the graphite surface, reducing its service life.

[0003] Due to the drawbacks of using graphite materials, the industries of monocrystalline silicon, indium phosphate, indium phosphide, and wafer fabrication have expanded rapidly. In the solar photovoltaic and semiconductor industries, improving material quality and reducing costs have become crucial for industrial development, urgently requiring extended service life of thermal field materials. Currently, C / C composite materials, as high-temperature composites that can be used at temperatures up to 2800℃, have resistivity similar to graphite. Therefore, using C / C composite materials as resistive heating elements, crucibles, flow guides, and insulation cylinders can effectively mitigate stress fracture at the junction of hot and cold ends caused by the temperature difference between the hot and cold ends of graphite heating elements. Moreover, based on its properties, large thin-walled heating elements can be manufactured, making more efficient use of the furnace volume.

[0004] However, in the semiconductor field, where special purity requirements are necessary, the use of a single C / C composite material as a material for heating elements, insulation cylinders, crucibles, and flow guide cylinders inevitably leads to carbon atom volatilization, posing new challenges to material purity requirements. Secondly, when used for pulling single-crystal silicon, the high-temperature silicon vapor reacts with the quartz crucible to generate oxidizing substances such as SiO, which corrodes the outer surface of the flow guide cylinder, crucible, and insulation cylinder, affecting their performance and reducing their service life. Furthermore, the pyrolytic carbon in the single C / C composite material will decompose, thus affecting the purity within the reaction chamber, the purity of the prepared material, and the mechanical properties and service life of the hot zone materials such as crucibles and insulation cylinders.

[0005] Currently, as an aerospace coating material, nano-silicon carbide coatings possess high thermal conductivity, low coefficient of thermal expansion, low carbon diffusion coefficient, stable chemical properties, and good wear resistance. They also exhibit advantages such as high temperature resistance, thermal shock resistance, creep resistance, and oxidation resistance. In the aerospace field, silicon carbide coatings have been used as high-temperature coatings for carbon materials and carbon / carbon composites, resisting gas flows at 2500-3000℃ and demonstrating excellent oxidation and ablation resistance. Applying silicon C coatings to carbon materials such as graphite heating elements in wafer growth furnaces in the semiconductor industry is expected to improve wafer quality by 3-5 times and extend the lifespan of carbon-carbon core components by 6-10 times, significantly enhancing enterprise economic benefits. Furthermore, zirconium carbide, a typical representative of ultra-high temperature ceramic materials, possesses ultra-high melting point, ultra-corrosion resistance, oxidation resistance, high hardness, and lower manufacturing costs compared to other ultra-high temperature ceramic materials. It has been widely used in high-temperature and oxygen-containing environments at 1800℃ and above, and is often matched with silicon C ceramics to prepare ceramic coatings.

[0006] However, although silicon carbide ceramics possess the aforementioned excellent thermochemical properties, during the growth of single-crystal materials at high or even higher temperatures, the presence of oxygen atoms in the atmosphere causes the single silicon carbide to corrode under SiO, forming SiO2 gas or SiO2 liquid. Furthermore, as oxygen atoms diffuse into the carbon-carbon composite material, they are reduced by carbon atoms, forming CO or CO2 gas. These oxygen-laden gases immediately accumulate on the single-crystal surface, causing corrosion and directly affecting the purity of the single-crystal growth. Secondly, although the silicon-C coating has a better match for the coefficient of thermal expansion with C / C composites compared to ultra-high temperature ceramics (such as ZrC, HfC, ZrB2, HfB2, etc.), in complex environments with large temperature differences and corrosive gases, the thermal compatibility between the silicon-C coating and the carbon-carbon composite remains a key factor hindering the long-term repeated use of the coating. Therefore, using a single silicon-C coating as the interface layer between the ceramic coating and the carbon-carbon composite cannot guarantee a smooth transition between the subsequent ultra-high temperature coating and the carbon-carbon composite. Summary of the Invention

[0007] This invention provides a coated carbonaceous material and its preparation method, which solves the technical problems of corrosion and insufficient coating bonding strength that occur during the growth of single crystal materials with existing single coatings.

[0008] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0009] A method for preparing a coated carbonaceous material includes the following steps:

[0010] (1) A microstructured groove is formed on the surface of a carbonaceous material matrix, and a metal catalyst layer is prepared on the surface of the carbonaceous material matrix.

[0011] (2) The carbonaceous material matrix is ​​impregnated with a silicon-containing slurry, wherein the silicon-containing slurry comprises 10 parts by weight of nano-silicon powder and 2 to 3 parts by weight of waxy carbon source.

[0012] (3) The carbonaceous material matrix that has been impregnated is placed in a reaction device and heated to grow a silicon carbide nanowire connecting layer to obtain intermediate product A.

[0013] (4) Place intermediate product A in a deposition apparatus and introduce dilution gas, silicon source gas and carbon source gas to deposit a silicon carbide nanowire reinforced silicon carbide layer on intermediate product A to obtain intermediate product B.

[0014] (5) A silicon carbide-zirconium carbide composite layer is deposited on the intermediate product B and post-processed to obtain intermediate product C.

[0015] (6) A zirconium carbide layer is deposited on the intermediate product C to obtain the coated carbonaceous material.

[0016] The design concept of the above technical solution is as follows: On the one hand, the present invention avoids the problems that occur in the semiconductor industry, especially in the single crystal growth process, when using a single silicon carbide coating, by sequentially preparing a silicon carbide nanowire-reinforced silicon carbide layer, a silicon carbide-zirconium carbide composite layer, and a zirconium carbide layer. Furthermore, the multi-layer coating structure design ensures a good transition and strong bonding strength between the high-temperature coating and the carbonaceous material substrate. On the other hand, the present invention also designs specific preparation methods for each layer of the coating: firstly, microstructured grooves are formed on the substrate surface and impregnated before preparing the silicon carbide nanowire connecting layer. The resulting silicon carbide nanowire connecting layer grows outward from the substrate surface as a site, and the constraint effect of the inner wall of the microstructured groove promotes the nucleation of SiC nanowires at the bottom of the groove, exhibiting a vertical orientation. The metal catalyst layer is composed of SiC nanowires. The nucleation of rice noodles and the guarantee factors for promoting the upright growth of SiC nanowires are as follows: Since the metal catalyst layer is a low-melting-point metal, the metal catalyst melts into small droplets during the heating process. After the metal droplets adsorb gaseous carbon and gaseous silicon sources and form a supersaturated state, SiC nanowire nuclei are precipitated and grow upright during the continuous adsorption process. The metal catalyst droplets are always at the top of the SiC nanowires. Based on the above mechanism, the silicon carbide nanowires grown on other planes of the substrate have a woven structure. This gives the silicon carbide nanowire connecting layer a unique structure of loose and porous longitudinal upright silicon carbide nanowires intersecting the planar silicon carbide woven structure. This structure plays a role in three-dimensional intersecting mechanical cooperation, connection and interface constraint. Silicon carbide is then deposited on this silicon carbide nanowire connecting layer with a unique structure for densification and coverage, which greatly improves the bonding strength between the coating and the substrate.

[0017] As a further preferred embodiment of the above technical solution, the carbonaceous material matrix is ​​selected with a density of 1.2–1.5 g / cm³. 3 Carbon-carbon composite materials.

[0018] As a further preferred embodiment of the above technical solution, the depth of the microstructure groove in step (1) is 10–20 μm and the width is 2–5 μm; the microstructure groove is formed by laser etching. This preferred embodiment uses laser etching to form microstructure grooves on the substrate surface, which promotes the preferential oxidation of the carbon fiber tips into a conical structure and forms CO bonds on the surface of the carbonaceous substrate, providing active sites for the subsequent growth of silicon carbide nanowires and effectively increasing the number of nanowires grown. The size of the microstructure grooves also has a significant impact on the production of silicon carbide nanowires: if the groove depth is too deep, greater than 20 μm, the silicon carbide nanowires will fall over inside the groove, causing blockage and affecting the upright growth of the nanowires. This will also result in the coating within the groove not being dense enough, forming voids and cracks, and reducing the bonding strength between the coating and the substrate. If the groove is too shallow, less than 10 μm deep, the grown silicon carbide nanowires will be too short to achieve the effect of vertically reinforcing the coating. Furthermore, the shallow grooves cannot effectively provide mechanical bonding between the coating and the groove walls, reducing the bonding strength between the coating and the substrate. If the groove is too wide, the constraint effect of the groove walls on the nanowires is too weak, causing the nanowires to fall over and affecting the coating density. When the groove is too narrow, nanowire growth is hindered, and the nanowires will grow tightly together, eventually growing into whiskers, which will block the groove pores and reduce the coating density. Therefore, the size of the groove structure has also undergone creative design and rigorous experimental verification.

[0019] As a further preferred embodiment of the above technical solution, the catalyst layer is a metal Fe or Ni layer, and the thickness of the catalyst layer is 5 to 10 μm.

[0020] As a further preferred embodiment of the above technical solution, the catalyst layer is prepared by electrochemical deposition at a temperature of 100–200°C for 5–10 min. The electrochemical deposition solution is a mixture of Fe or Ni dispersed in deionized water, with a Fe or Ni mass concentration of 10%–20%. The electrochemical deposition method effectively controls the growth thickness and distribution of the catalyst on the surface of the composite material, providing a catalytic promotion effect for the subsequent formation of nanowires extending from the interior to the exterior of the substrate with excellent verticality.

[0021] As a further preferred embodiment of the above technical solution, the impregnation treatment in step (2) is performed as follows: the silicon-containing slurry is brushed onto the surface of the carbonaceous material substrate and impregnated by rotation at room temperature; the number of brushings is 3 to 5, and after each brushing, it is dried at room temperature for 2 to 10 minutes; the impregnation time is 1 to 3 hours, and the rotation speed is 10 to 30 revolutions. The impregnation treatment with brushing and room temperature rotation ensures that the silicon particles and liquid paraffin required for the formation of silicon carbide nanowires are uniformly distributed in the microstructure grooves and surface micropores, which promotes the extension of silicon carbide nanowires from the inside to the outside from the microstructure grooves and other surface areas. This is beneficial to the formation of the three-dimensional interconnected structure and provides a favorable auxiliary effect for the subsequent nanowire-reinforced outer coating.

[0022] As a further preferred embodiment of the above technical solution, the particle size of the nano-silicon powder is less than 100 nm.

[0023] As a further preferred embodiment of the above technical solution, in the heating growth process of the silicon carbide nanowire connecting layer in step (3), the silicon carbide nanowires are first heated and grown under vacuum conditions for 1 to 2 hours, and then dilution gas, silicon source gas and carbon source gas are introduced into the reaction device to continue growth for 0.5 to 2 hours. Through the above-mentioned stepped gas-breathing method of this preferred embodiment, it can be ensured that slender silicon carbide nanowires are grown at low temperature in the early stage. The introduction of raw material gas and dilution gas in the later stage can promote the formation of silicon carbide protrusions at the missing wire sites on the wall of the silicon carbide nanowires, so that the silicon carbide nanowires finally formed are grown into bamboo joints. The bamboo joints of silicon carbide nanowires have a toughening and interfacial riveting effect on the other layers of the coating set on them. During the extraction process, the bamboo joints of nanowires form a special mechanical interlocking effect and a new toughening mechanism such as microcrack toughening with their own nodes and the surrounding coating substrate, which effectively improves the mechanical linkage between the silicon carbide nanowire connecting layer and the subsequent coating, and ultimately effectively improves the interfacial bonding strength between the coating and the substrate.

[0024] As a further preferred embodiment of the above technical solution, the growth temperature of the silicon carbide nanowire connecting layer in step (3) is 1100-1350℃, and the growth time is 1.5-4h; the volume ratio of the carbon source gas to the silicon source gas is 1:(2-4), and the volume of the dilution gas is 3-5 times the total volume of the carbon source gas and the silicon source gas.

[0025] As a further preferred embodiment of the above technical solution, the thickness of the silicon carbide nanowire connecting layer is 100–150 μm.

[0026] As a further preferred embodiment of the above technical solution, the deposition temperature of the silicon carbide nanowire-reinforced silicon carbide layer in step (4) is 1000-1400℃, the deposition time is 5-20h, and the deposition atmosphere is a protective atmosphere.

[0027] As a further preferred embodiment of the above technical solution, the thickness of the silicon carbide nanowire-reinforced silicon carbide layer is 120–175 μm.

[0028] As a further preferred embodiment of the above technical solution, the carbon source gas in steps (3) and (4) is methane, the silicon source gas is silicon tetrachloride, and the dilution gas is hydrogen.

[0029] As a further preferred embodiment of the above technical solution, the silicon carbide-zirconium carbide composite layer in step (5) is obtained by deposition using a two-phase gas introduction method. The introduced gas is silicon tetrachloride, zirconium tetrachloride carbon source gas and dilution gas. The molar ratio of silicon tetrachloride and zirconium tetrachloride is 1:1, the carbon source gas is methane and the dilution gas is hydrogen.

[0030] As a further preferred embodiment of the above technical solution, the post-processing operation in step (5) involves placing the carbonaceous material matrix in a heat treatment furnace covered with silicon powder for heat treatment at a temperature of 2000–2200°C for 1–2 hours. After heat treatment, the β-silicon C layer deposited by chemical vapor deposition is transformed into an α-silicon C layer. Under the action of silicon vapor deposition, the pores and cracks caused by the high-temperature phase transition of the silicon carbide nanowire-reinforced silicon carbide layer are effectively filled, promoting the further formation of a dense, high-temperature stable silicon carbide nanowire-reinforced silicon carbide layer.

[0031] As a further preferred embodiment of the above technical solution, the total thickness of the silicon carbide nanowire connecting layer, the silicon carbide nanowire reinforced silicon carbide layer, and the silicon carbide-zirconium carbide composite layer is 150-205 μm.

[0032] As a further preferred embodiment of the above technical solution, the zirconium carbide layer in step (6) is prepared by high-temperature chemical vapor deposition, with a deposition temperature of 1700-1800℃, a deposition time of 3-5h, a raw material gas of zirconium tetrachloride, a dilution gas of hydrogen, and a volume ratio of raw material gas to dilution gas of 1:1.

[0033] As a further preferred embodiment of the above technical solution, the thickness of the zirconium carbide coating is 30–50 μm.

[0034] Based on a unified technical concept, the present invention also provides a coated carbonaceous material, which is prepared by the preparation method of the above-described technical solution.

[0035] Compared with the prior art, the advantages of the present invention are as follows:

[0036] This invention, through the design of the fabrication process of each layer of the coating on the substrate surface, obtains a carbonaceous material with a special surface microstructure. On the one hand, it avoids the problems that occur in the semiconductor industry, especially in the single crystal growth process, when using a single silicon carbide coating in the prior art. The multi-layer coating structure design ensures a good transition and strong bonding strength between the high-temperature coating and the carbonaceous material substrate. On the other hand, it effectively improves the surface roughness, causing the coating formed on the substrate surface to present a three-dimensional interpenetrating mechanical fit structure with the substrate. Through the mechanical connection and interface constraint effect of the three-dimensional interpenetrating structure, the interfacial bonding strength between the coating and the substrate is effectively improved. Detailed Implementation

[0037] The present invention will be further described in detail below with reference to specific embodiments.

[0038] Example 1:

[0039] The method for preparing the coated carbonaceous material in this embodiment includes the following steps:

[0040] (1) Select a density of 1.5 g / cm³ 3 Carbon-carbon composite materials are used as the matrix of composite materials.

[0041] (2) A microstructure groove with a depth of 20 μm and a width of 5 μm was prepared on the surface of the carbon-carbon composite material by laser etching.

[0042] (3) A metal catalyst layer was prepared on the surface of carbon-carbon composite material by electrochemical deposition. The catalyst was selected as metal Fe, and the thickness of the catalyst layer was 10 μm. The solution for electrochemical deposition was prepared as follows: deionized water was selected as the electrodeposition liquid carrier, and the concentration of metal Fe added to the catalyst was 20%. The electrochemical deposition temperature was 200℃, the deposition time was 10 min, and the deposition atmosphere was argon protective atmosphere.

[0043] (4) Prepare a silica-containing slurry and apply the silica-containing slurry to the carbon-carbon composite material with microstructure grooves by immersion brushing method, and then perform room temperature rotary impregnation treatment; wherein, the silica-containing slurry includes nano-sized silicon powder (silicon powder diameter is 60nm) and liquid paraffin, and the liquid paraffin accounts for 30% of the mass of silicon powder; during the room temperature rotary impregnation process, the rotation speed is 30s / 360°, the impregnation time is 3h, and the impregnation atmosphere is air.

[0044] To ensure a uniform coating of silicon particles on the surface of the carbon-carbon composite material, a brush coating process was performed on the surface of the carbon-carbon composite material under static conditions using an immersion brush coating method. The brush coating was performed 5 times, and after each brush coating, the material was dried at room temperature for 10 minutes. This process ensured that the surface of the carbon-carbon composite material had a uniformly distributed layer of silicon particles, which would serve as the core for subsequent silicon carbide nanoparticles. The thickness of the silicon particle layer after brush coating was 5 μm.

[0045] (5) A silicon carbide nanowire connecting layer is grown inside the microstructure groove and on the surface of the carbon-carbon composite material. During the preparation process, a carbon source gas and a silicon source gas (collectively referred to as raw material gas) with a volume ratio of 1:2 and a dilution gas are introduced, and the volume of the dilution gas is 5 times that of the raw material gas. In this embodiment, methane is used as the carbon source gas, silicon tetrachloride is used as the silicon source gas, and hydrogen is used as the dilution gas. The carbon source gas, silicon source gas, and dilution gas are introduced in the following way: First, silicon source gas, carbon source gas, and dilution gas are not introduced in the first two hours of the growth process to ensure that the silicon carbide nanowires form ultra-fine and long silicon carbide nanowires (with a diameter of 50 nm) under the reaction of the carbon source gas and nano silicon powder provided by liquid paraffin. In the third to fourth hours of the growth process, silicon source gas, carbon source gas, and dilution gas (with a gas flow rate of 5 L / min) are introduced to carry out the reaction. Before venting, the gas inside the reactor needs to be evacuated to ensure the discharge of residual liquid paraffin decomposition products; during the growth process, the growth temperature is 1350℃, the growth time is 4h, and the growth atmosphere is a vacuum state; the thickness of the silicon carbide nanowire connecting layer obtained by this step is 150μm.

[0046] (6) After preparing the silicon carbide nanowire connecting layer, silicon carbide is deposited on the surface and inside of the loose and porous silicon carbide nanowire layer to densify the silicon carbide nanowire connecting layer, and finally a silicon carbide nanowire-reinforced silicon carbide layer is prepared. Among them, silicon carbide is deposited by chemical vapor deposition at a deposition temperature of 1000℃ and a deposition time of 20h. The deposition atmosphere is an argon protective atmosphere. The thickness of the silicon carbide nanowire-reinforced silicon carbide layer obtained in this step is 175μm.

[0047] (7) After preparing the silicon carbide nanowire-reinforced silicon carbide layer, a silicon carbide-zirconium carbide composite coating is prepared by a two-phase chemical vapor deposition method. When preparing the coating by the two-phase chemical vapor deposition method, silicon tetrachloride and zirconium tetrachloride gas (molar ratio of the two is 1:1) are introduced simultaneously, and H2 is introduced as a dilution gas (molar ratio of raw material gas to dilution gas is 1:1). The deposition temperature is 1500℃, the deposition time is 20h, and the deposition atmosphere is argon protective gas.

[0048] (8) The substrate after the preparation of the silicon carbide-zirconium carbide composite coating was subjected to high-temperature heat treatment in a heat treatment furnace with silicon powder to achieve a high-temperature stable phase transformation of each silicon carbide phase. At the same time, the pores and cracks in the coating were sealed and repaired under high-temperature thermal evaporation of silicon powder. The heat treatment temperature was 2100℃, the heat treatment time was 2h, and the heat treatment atmosphere was argon protective gas. The total thickness of the coating after this step was 205μm.

[0049] (9) A nanoscale, highly dense zirconium carbide coating is prepared on the substrate surface by high-temperature chemical vapor deposition, thus obtaining the carbonaceous material with coating in this embodiment; the chemical vapor deposition temperature is 1800℃, the deposition time is 5h, the raw material gas is zirconium tetrachloride, the diluent gas is hydrogen, the volume ratio of the two is 1:1, and the thickness of the zirconium carbide coating obtained in this step is 40μm.

[0050] The thermal shock resistance of the coated carbonaceous material in this embodiment was tested by cycling it 10 times from 1800°C to room temperature. It was found that the coating did not crack and the coating had excellent adhesion to the substrate.

[0051] The corrosion resistance of the coated carbonaceous material in this embodiment was tested using concentrated hydrochloric acid and nitric acid. The results showed that the coating surface remained intact and no obvious corrosion was observed.

[0052] The coated carbonaceous material of this embodiment was subjected to high-temperature corrosion resistance testing in an environment with SiO vapor at 1800°C. It was found that no obvious ceramic oxidation was observed on the substrate surface, no oxidation was observed in the internal carbon fibers, and the structure remained intact without any coating peeling.

[0053] Comparative Example 1:

[0054] This comparative example uses a density of 1.5 g / cm³. 3 The carbon-carbon composite material was subjected to corrosion with concentrated hydrochloric acid and nitric acid. It was found that corrosion pits appeared on the carbon layer on the surface of the carbon-carbon composite material, but the corrosion was not obvious.

[0055] Select a material with a density of 1.5 g / cm³. 3 The carbon-carbon composite material was subjected to high-temperature corrosion resistance testing in an environment with SiO vapor at 1800℃. The results showed that the carbon fibers of the carbon-carbon composite material oxidized, became less brittle, and formed a loose and porous SiCO layer on the surface.

[0056] Comparative Example 2:

[0057] The preparation method of the carbonaceous material in this comparative example includes the following steps:

[0058] (1) Select a density of 1.5 g / cm³ 3 Carbon-carbon composite materials are used as the matrix of composite materials.

[0059] (2) A microstructure groove with a depth of 20 μm and a width of 5 μm was prepared on the surface of the carbon-carbon composite material by laser etching.

[0060] (3) A metal catalyst layer was prepared on the surface of carbon-carbon composite material by electrochemical deposition. The catalyst was selected as metal Fe, and the thickness of the catalyst layer was 10 μm. The solution for electrochemical deposition was prepared as follows: deionized water was selected as the electrodeposition liquid carrier, and the concentration of metal Fe added to the catalyst was 20%. The electrochemical deposition temperature was 200℃, the deposition time was 10 min, and the deposition atmosphere was argon protective atmosphere.

[0061] (4) Prepare a silica-containing slurry and apply the silica-containing slurry to the carbon-carbon composite material with microstructure grooves by immersion brushing method, and then perform room temperature rotary impregnation treatment; wherein, the silica-containing slurry includes nano-sized silicon powder (silicon powder diameter is 60nm) and liquid paraffin, and the liquid paraffin accounts for 30% of the mass of silicon powder; during the room temperature rotary impregnation process, the rotation speed is 30s / 360°, the impregnation time is 3h, and the impregnation atmosphere is air.

[0062] To ensure a uniform coating of silicon particles on the surface of the carbon-carbon composite material, a brush coating process was performed on the surface of the carbon-carbon composite material under static conditions using an immersion brush coating method. The brush coating was performed 5 times, and after each brush coating, the material was dried at room temperature for 10 minutes. This process ensured that the surface of the carbon-carbon composite material had a uniformly distributed layer of silicon particles, which would serve as the core for subsequent silicon carbide nanoparticles. The thickness of the silicon particle layer after brush coating was 5 μm.

[0063] (5) A silicon carbide nanowire connecting layer is grown inside the microstructure groove and on the surface of the carbon-carbon composite material. During the preparation process, no carbon source gas or silicon source gas (the two are collectively referred to as raw material gas) or dilution gas is introduced. During the growth process, the growth temperature is 1350℃, the growth time is 4h, and the growth atmosphere is vacuum. The thickness of the silicon carbide nanowire connecting layer grown in this step is 150μm.

[0064] (6) After preparing the silicon carbide nanowire connecting layer, silicon carbide is deposited on the surface and inside of the loose and porous silicon carbide nanowire layer to densify the silicon carbide nanowire connecting layer, and finally a silicon carbide nanowire layer with a three-dimensional mosaic structure reinforced by silicon carbide nanowire is prepared. Among them, silicon carbide is deposited by chemical vapor deposition at a deposition temperature of 1000℃ and a deposition time of 20h. The deposition atmosphere is an argon protective atmosphere. The thickness of the silicon carbide nanowire reinforced silicon carbide layer obtained in this step is 175μm.

[0065] (7) After preparing the silicon carbide nanowire-reinforced silicon carbide layer, a silicon carbide-zirconium carbide composite coating is prepared by a two-phase chemical vapor deposition method. When preparing the coating by the two-phase chemical vapor deposition method, silicon tetrachloride and zirconium tetrachloride gas (molar ratio of the two is 1:1) are introduced simultaneously, and H2 is introduced as a dilution gas (molar ratio of raw material gas to dilution gas is 1:1). The deposition temperature is 1500℃, the deposition time is 20h, and the deposition atmosphere is argon protective gas.

[0066] (8) The substrate after the preparation of the silicon carbide-zirconium carbide composite coating was subjected to high-temperature heat treatment in a heat treatment furnace with silicon powder to achieve a high-temperature stable phase transformation of each silicon carbide phase. At the same time, the pores and cracks in the coating were sealed and repaired under the high-temperature thermal evaporation of silicon powder. The heat treatment temperature was 2100℃, the heat treatment time was 2h, and the heat treatment atmosphere was argon protective gas. The total thickness of the coating after this step was 160μm.

[0067] (9) A nanoscale, highly dense zirconium carbide coating was prepared on the substrate surface by high-temperature chemical vapor deposition, thus obtaining the carbonaceous material with coating in this comparative example; the chemical vapor deposition temperature was 1800℃, the deposition time was 5h, the raw material gas was zirconium tetrachloride, the dilution gas was hydrogen, and the volume ratio of the two was 1:1. The thickness of the zirconium carbide coating obtained in this step was 40μm.

[0068] The thermal shock resistance of the coated carbonaceous material in this comparative example was tested by cycling it 10 times from 1800°C to room temperature. Cracking was found between the silicon carbide coating and the substrate. Compared with Example 1, there was no mechanical bonding effect of the bamboo-like silicon carbide nanowires, and the interfacial bonding strength between the silicon carbide coating and the substrate was reduced.

[0069] The corrosion resistance of the coated carbonaceous material in this comparative example was tested using concentrated hydrochloric acid and nitric acid. It was found that corrosion occurred inside the silicon carbide nanowire-reinforced silicon carbide coating. The main reason is that before the silicon carbide nanowires underwent bamboo-like growth, the silicon carbide nanowire layer had many pores. In the end, the silicon carbide nanowire-reinforced silicon carbide layer was not completely densified. The pores and cracks provided corrosion active sites, which accelerated the corrosion of the coating.

[0070] The coated carbonaceous material of this comparative example was subjected to high-temperature corrosion resistance testing in an environment with SiO vapor at 1800℃. It was found that oxygen-containing atmosphere diffused inward through the pores of the ceramic coating, causing oxidation of the carbon fiber and a small amount of coating peeling off.

[0071] Comparative Example 3:

[0072] The preparation method of the coated carbonaceous material in this comparative example includes the following steps:

[0073] (1) Select a density of 1.5 g / cm³ 3 Carbon-carbon composite materials are used as the matrix of composite materials.

[0074] (2) A metal catalyst layer was prepared on the surface of carbon-carbon composite material by electrochemical deposition. The catalyst was metal Fe, and the thickness of the catalyst layer was 10 μm. The solution for electrochemical deposition was prepared as follows: deionized water was used as the electrodeposition liquid carrier, and the concentration of metal Fe added to the catalyst was 20%. The electrochemical deposition temperature was 200℃, the deposition time was 10 min, and the deposition atmosphere was argon protective atmosphere.

[0075] (3) Prepare a silicon-containing slurry and apply the silicon-containing slurry to the carbon-carbon composite material by immersion brushing method, and then perform room temperature rotary impregnation treatment; wherein, the silicon-containing slurry includes nano-sized silicon powder (silicon powder diameter is 60nm) and liquid paraffin, the liquid paraffin accounts for 30% of the mass of silicon powder; during the room temperature rotary impregnation process, the rotation speed is 30s / 360°, the impregnation time is 3h, and the impregnation atmosphere is air.

[0076] To ensure a uniform coating of silicon particles on the surface of the carbon-carbon composite material, a brush coating process was performed on the surface of the carbon-carbon composite material under static conditions using an immersion brush coating method. The brush coating was performed 5 times, and after each brush coating, the material was dried at room temperature for 10 minutes. This process ensured that the surface of the carbon-carbon composite material had a uniformly distributed layer of silicon particles, which would serve as the core for subsequent silicon carbide nanoparticles. The thickness of the silicon particle layer after brush coating was 5 μm.

[0077] (4) A silicon carbide nanowire connecting layer is grown on the surface of a carbon-carbon composite material. During the preparation process, a carbon source gas and a silicon source gas (collectively referred to as raw material gas) with a volume ratio of 1:2 and a dilution gas are introduced, and the volume of the dilution gas is 5 times that of the raw material gas. In this comparative example, methane is used as the carbon source gas, silicon tetrachloride is used as the silicon source gas, and hydrogen is used as the dilution gas. The carbon source gas, silicon source gas, and dilution gas are introduced in the following way: First, silicon source gas, carbon source gas, and dilution gas are not introduced in the first two hours of the growth process to ensure that the silicon carbide nanowires form ultra-fine and long silicon carbide nanowires (with a diameter of 50 nm) under the reaction of the carbon source gas and nano silicon powder provided by liquid paraffin. In the third to fourth hours of the growth process, silicon source gas, carbon source gas, and dilution gas (with a gas flow rate of 5 L / min) are introduced to carry out the reaction. Before venting, the gas inside the reactor needs to be evacuated to ensure the discharge of residual liquid paraffin decomposition products. During the growth process, the growth temperature is 1350℃, the growth time is 4h, and the growth atmosphere is a vacuum. The thickness of the silicon carbide nanowire connecting layer grown in this step is 100μm, which is lower than the thickness in Example 1 without grooves. This is mainly because without the constraint of the grooves, the nanowires collapse, resulting in a reduction in coating thickness.

[0078] (5) After preparing the silicon carbide nanowire connecting layer, silicon carbide is deposited on the surface and inside of the loose and porous silicon carbide nanowire layer to densify the silicon carbide nanowire connecting layer, and finally a silicon carbide nanowire-reinforced silicon carbide layer is prepared. Among them, silicon carbide is deposited by chemical vapor deposition at a deposition temperature of 1000℃ and a deposition time of 20h. The deposition atmosphere is argon protective atmosphere. The thickness of the silicon carbide nanowire-reinforced silicon carbide layer obtained in this step is 120μm.

[0079] (6) After preparing the silicon carbide nanowire-reinforced silicon carbide layer, a silicon carbide-zirconium carbide composite coating is prepared by a two-phase chemical vapor deposition method. When preparing the coating by the two-phase chemical vapor deposition method, silicon tetrachloride and zirconium tetrachloride gas (molar ratio of the two is 1:1) are introduced simultaneously, and H2 is introduced as a dilution gas (molar ratio of raw material gas to dilution gas is 1:1). The deposition temperature is 1500℃, the deposition time is 20h, and the deposition atmosphere is argon protective gas.

[0080] (7) The substrate after the preparation of the silicon carbide-zirconium carbide composite coating was subjected to high-temperature heat treatment in a heat treatment furnace with silicon powder to achieve a high-temperature stable phase transformation of each silicon carbide phase. At the same time, the pores and cracks in the coating were sealed and repaired under high-temperature thermal evaporation of silicon powder. The heat treatment temperature was 2100℃, the heat treatment time was 2h, and the heat treatment atmosphere was argon protective gas. The total thickness of the coating after this step was 140μm.

[0081] (8) A nanoscale, highly dense zirconium carbide coating was prepared on the substrate surface by high-temperature chemical vapor deposition, thus obtaining the carbonaceous material with coating in this comparative example; the chemical vapor deposition temperature was 1800℃, the deposition time was 5h, the raw material gas was zirconium tetrachloride, the dilution gas was hydrogen, and the volume ratio of the two was 1:1. The thickness of the zirconium carbide coating obtained in this step was 40μm.

[0082] The thermal shock resistance of the carbonaceous material in this comparative example was tested by cycling it 10 times from 1800°C to room temperature. Cracking was found between the silicon carbide coating and the substrate. Compared with Example 1 and Comparative Example 1, without the groove, the carbonized layer on the surface of the carbon-carbon composite material could not form a three-dimensional mosaic structure. The wall constraint force of the three-dimensional mosaic could not be provided, and the mechanical bonding effect could not be provided. The interfacial bonding strength between the silicon carbide coating and the substrate was reduced compared with Example 1 and Comparative Example 1.

[0083] The corrosion resistance of the coated carbonaceous material in this comparative example was tested using concentrated hydrochloric acid and nitric acid. It was found that corrosion occurred inside the silicon carbide nanowire-reinforced silicon carbide coating. The main reason was the lack of grooves, which caused the silicon carbide nanowires to collapse and have many pores. Ultimately, this prevented the formation of a dense ceramic layer. The pores and cracks provided corrosion active sites, accelerating the corrosion of the coating.

[0084] The coated carbonaceous material of this comparative example was subjected to high-temperature corrosion resistance testing in an environment with SiO vapor at 1800℃. It was found that oxygen-containing atmosphere diffused inward through the pores of the ceramic coating, causing oxidation of the carbon fiber and a small amount of coating peeling off.

[0085] Example 2:

[0086] The method for preparing the coated carbonaceous material in this embodiment includes the following steps:

[0087] (1) Select a density of 1.2 g / cm³ 3 Carbon-carbon composite materials are used as the matrix of composite materials.

[0088] (2) A microstructure groove with a depth of 10 μm and a width of 2 μm was prepared on the surface of carbon-carbon composite material by laser etching.

[0089] (3) A metal catalyst layer was prepared on the surface of carbon-carbon composite material by electrochemical deposition. The catalyst was metal Ni and the thickness of the catalyst layer was 5 μm. The solution for electrochemical deposition was prepared as follows: deionized water was used as the electrodeposition liquid carrier and the concentration of metal Ni added to the catalyst was 10%. The electrochemical deposition temperature was 100℃, the deposition time was 5 min, and the deposition atmosphere was argon protective atmosphere.

[0090] (4) Prepare a silica-containing slurry and apply the silica-containing slurry to the carbon-carbon composite material with microstructure grooves by immersion brushing method, and then perform room temperature rotary impregnation treatment; wherein, the silica-containing slurry includes nano-sized silicon powder (silicon powder diameter is 80nm) and liquid paraffin, and the liquid paraffin accounts for 20% of the mass of silicon powder; during the room temperature rotary impregnation process, the rotation speed is 10s / 360°, the impregnation time is 1h, and the impregnation atmosphere is air.

[0091] To ensure a uniform coating of silicon particles on the surface of the carbon-carbon composite material, the surface was coated using an immersion-brush method under static conditions. The brushing process was repeated three times, with each brushing followed by 2 minutes of room temperature drying. This ensured that the surface of the carbon-carbon composite material had a uniformly distributed layer of silicon particles, which would serve as the core for subsequent silicon carbide nanoparticles. The thickness of the silicon particle layer after brushing was 1 μm.

[0092] (5) A silicon carbide nanowire connecting layer is grown inside the microstructure groove and on the surface of the carbon-carbon composite material. During the preparation process, a carbon source gas and a silicon source gas (collectively referred to as raw material gas) with a volume ratio of 1:4 and a dilution gas are introduced, and the volume of the dilution gas is 3 times that of the raw material gas. In this embodiment, methane is used as the carbon source gas, silicon tetrachloride is used as the silicon source gas, and hydrogen is used as the dilution gas. The carbon source gas, silicon source gas, and dilution gas are introduced in the following way: First, silicon source gas, carbon source gas, and dilution gas are not introduced in the first two hours of the growth process to ensure that the silicon carbide nanowires form ultra-fine and long silicon carbide nanowires (diameter of 20 nm) under the reaction of the carbon source gas and nano silicon powder provided by liquid paraffin. In the third to fourth hours of the growth process, silicon source gas, carbon source gas, and dilution gas (gas flow rate of 2 L / min) are introduced to carry out the reaction. Before venting, the gas inside the reactor needs to be evacuated to ensure the discharge of residual liquid paraffin decomposition products; during the growth process, the growth temperature is 1100℃, the growth time is 1h, and the growth atmosphere is a vacuum state; the thickness of the silicon carbide nanowire interconnect layer obtained by this step is 100μm.

[0093] (6) After preparing the silicon carbide nanowire connecting layer, silicon carbide is deposited on the surface and inside of the loose and porous silicon carbide nanowire layer to densify the silicon carbide nanowire connecting layer, and finally a silicon carbide nanowire-reinforced silicon carbide layer is prepared. Among them, silicon carbide is deposited by chemical vapor deposition at a deposition temperature of 1400℃ and a deposition time of 5h. The deposition atmosphere is argon protective atmosphere. The thickness of the silicon carbide nanowire-reinforced silicon carbide layer obtained in this step is 50μm.

[0094] (7) After preparing the silicon carbide nanowire-reinforced silicon carbide layer, a silicon carbide-zirconium carbide composite coating is prepared by a two-phase chemical vapor deposition method. When preparing the coating by the two-phase chemical vapor deposition method, silicon tetrachloride and zirconium tetrachloride gas (molar ratio of the two is 1:1) are introduced simultaneously, and H2 is introduced as a dilution gas (molar ratio of raw material gas to dilution gas is 1:1). The deposition temperature is 1400℃, the deposition time is 5h, and the deposition atmosphere is argon protective gas.

[0095] (8) The substrate after the preparation of the silicon carbide-zirconium carbide composite coating was subjected to high-temperature heat treatment in a heat treatment furnace with silicon powder to achieve a high-temperature stable phase transformation of each silicon carbide phase. At the same time, the pores and cracks in the coating were sealed and repaired under the high-temperature thermal evaporation of silicon powder. The heat treatment temperature was 2100℃, the heat treatment time was 1h, and the heat treatment atmosphere was argon protective gas. The total thickness of the coating after this step was 130μm.

[0096] (9) A nanoscale, highly dense zirconium carbide coating is prepared on the substrate surface by high-temperature chemical vapor deposition, thus obtaining the carbonaceous material with coating in this embodiment; the chemical vapor deposition temperature is 1800℃, the deposition time is 5h, the raw material gas is zirconium tetrachloride, the diluent gas is hydrogen, the volume ratio of the two is 1:1, and the thickness of the zirconium carbide coating obtained in this step is 40μm.

[0097] The thermal shock resistance of the coated carbonaceous material in this embodiment was tested by cycling it 10 times from 1800°C to room temperature. It was found that the coating did not crack and the coating had excellent adhesion to the substrate.

[0098] The corrosion resistance of the coated carbonaceous material in this embodiment was tested using concentrated hydrochloric acid and nitric acid. The results showed that the coating surface remained intact and no obvious corrosion was observed.

[0099] The coated carbonaceous material of this embodiment was subjected to high-temperature corrosion resistance testing in an environment with SiO vapor at 1800°C. It was found that no obvious ceramic oxidation was observed on the substrate surface, no oxidation was observed in the internal carbon fibers, and the structure remained intact without any coating peeling.

[0100] Example 3:

[0101] The method for preparing the coated carbonaceous material in this embodiment includes the following steps:

[0102] (1) Select a density of 1.3 g / cm³ 3 Carbon-carbon composite materials are used as the matrix of composite materials.

[0103] (2) A microstructure groove with a depth of 15 μm and a width of 4 μm was prepared on the surface of carbon-carbon composite material by laser etching.

[0104] (3) A metal catalyst layer was prepared on the surface of carbon-carbon composite material by electrochemical deposition. The catalyst was metal Ni and the thickness of the catalyst layer was 8 μm. The solution for electrochemical deposition was prepared as follows: deionized water was used as the electrodeposition liquid carrier and the concentration of metal Ni added to the catalyst was 15%. The electrochemical deposition temperature was 150℃, the deposition time was 8 min, and the deposition atmosphere was argon protective atmosphere.

[0105] (4) Prepare a silica-containing slurry and apply the silica-containing slurry to the carbon-carbon composite material with microstructure grooves by immersion brushing method, and then perform room temperature rotary impregnation treatment; wherein, the silica-containing slurry includes nano-sized silicon powder (silicon powder diameter of 50nm) and liquid paraffin, and the liquid paraffin accounts for 15% of the mass of silicon powder; during the room temperature rotary impregnation process, the rotation speed is 20s / 360°, the impregnation time is 2h, and the impregnation atmosphere is air.

[0106] To ensure a uniform coating of silicon particles on the surface of the carbon-carbon composite material, a brush coating process was performed on the surface of the carbon-carbon composite material under static conditions using an immersion brush coating method. The brush coating was performed once, and after each brush coating, the material was dried at room temperature for 7 minutes. This process ensured that the surface of the carbon-carbon composite material had a uniformly distributed layer of silicon particles, which would serve as the core for subsequent silicon carbide nanoparticles. The thickness of the silicon particle layer after brush coating was 3 μm.

[0107] (5) A silicon carbide nanowire connecting layer is grown inside the microstructure groove and on the surface of the carbon-carbon composite material. During the preparation process, a carbon source gas and a silicon source gas (collectively referred to as raw material gas) with a volume ratio of 1:3 and a dilution gas are introduced, and the volume of the dilution gas is 4 times that of the raw material gas. In this embodiment, methane is used as the carbon source gas, silicon tetrachloride is used as the silicon source gas, and hydrogen is used as the dilution gas. The carbon source gas, silicon source gas, and dilution gas are introduced in the following way: First, silicon source gas, carbon source gas, and dilution gas are not introduced in the first two hours of the growth process to ensure that the silicon carbide nanowires form ultra-fine and long silicon carbide nanowires (diameter of 20 nm) under the reaction of the carbon source gas and nano silicon powder provided by liquid paraffin. In the third to fourth hours of the growth process, silicon source gas, carbon source gas, and dilution gas (gas flow rate of 2 L / min) are introduced to carry out the reaction. Before venting, the gas inside the reactor needs to be evacuated to ensure the discharge of residual liquid paraffin decomposition products; during the growth process, the growth temperature is 1200℃, the growth time is 3h, and the growth atmosphere is a vacuum state; the thickness of the silicon carbide nanowire connecting layer obtained by this step is 100μm.

[0108] (6) After preparing the silicon carbide nanowire connecting layer, silicon carbide is deposited on the surface and inside of the loose and porous silicon carbide nanowire layer to densify the silicon carbide nanowire connecting layer, and finally a silicon carbide nanowire-reinforced silicon carbide layer is prepared. Among them, silicon carbide is deposited by chemical vapor deposition at a deposition temperature of 1200℃ and a deposition time of 15h. The deposition atmosphere is an argon protective atmosphere. The thickness of the silicon carbide nanowire-reinforced silicon carbide layer obtained in this step is 50μm.

[0109] (7) After preparing the silicon carbide nanowire-reinforced silicon carbide layer, a silicon carbide-zirconium carbide composite coating is prepared by a two-phase chemical vapor deposition method. When preparing the coating by the two-phase chemical vapor deposition method, silicon tetrachloride and zirconium tetrachloride gas (molar ratio of the two is 1:1) are introduced simultaneously, and H2 is introduced as a dilution gas (molar ratio of raw material gas to dilution gas is 1:1). The deposition temperature is 1350℃, the deposition time is 15h, and the deposition atmosphere is argon protective gas.

[0110] (8) The substrate after the preparation of the silicon carbide-zirconium carbide composite coating was subjected to high-temperature heat treatment in a heat treatment furnace with silicon powder to achieve a high-temperature stable phase transformation of each silicon carbide phase. At the same time, the pores and cracks in the coating were sealed and repaired under high-temperature thermal evaporation of silicon powder. The heat treatment temperature was 2100℃, the heat treatment time was 1.5h, and the heat treatment atmosphere was argon protective gas. The total thickness of the coating after this step was 130μm.

[0111] (9) A nanoscale, highly dense zirconium carbide coating is prepared on the substrate surface by high-temperature chemical vapor deposition, thus obtaining the carbonaceous material with coating in this embodiment; the chemical vapor deposition temperature is 1800℃, the deposition time is 5h, the raw material gas is zirconium tetrachloride, the diluent gas is hydrogen, the volume ratio of the two is 1:1, and the thickness of the zirconium carbide coating obtained in this step is 40μm.

[0112] The thermal shock resistance of the coated carbonaceous material in this embodiment was tested by cycling it 10 times from 1800°C to room temperature. It was found that the coating did not crack and the coating had excellent adhesion to the substrate.

[0113] The corrosion resistance of the coated carbonaceous material in this embodiment was tested using concentrated hydrochloric acid and nitric acid. The results showed that the coating surface remained intact and no obvious corrosion was observed.

[0114] The coated carbonaceous material of this embodiment was subjected to high-temperature corrosion resistance testing in an environment with SiO vapor at 1800°C. It was found that no obvious ceramic oxidation was observed on the substrate surface, no oxidation was observed in the internal carbon fibers, and the structure remained intact without any coating peeling.

[0115] The above description is merely a preferred embodiment of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. For those skilled in the art, improvements and modifications obtained without departing from the inventive concept should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a coated carbonaceous material, characterized in that, Includes the following steps: (1) A microstructured groove is formed on the surface of a carbonaceous material matrix, and a metal catalyst layer is prepared on the surface of the carbonaceous material matrix; the depth of the microstructured groove is 10-20 μm and the width is 2-5 μm; the microstructured groove is formed by laser etching. (2) The carbonaceous material matrix is ​​impregnated with a silicon-containing slurry, wherein the silicon-containing slurry comprises 10 parts by weight of nano-silicon powder and 2 to 3 parts by weight of waxy carbon source; (3) The impregnated carbonaceous material matrix is ​​placed in a reaction device and heated to grow a silicon carbide nanowire connecting layer to obtain intermediate product A; during the heating growth of the silicon carbide nanowire connecting layer, it is first heated and grown under vacuum conditions for 1 to 2 hours, and then dilution gas, silicon source gas and carbon source gas are introduced into the reaction device to continue growth for 0.5 to 2 hours; the growth temperature of the silicon carbide nanowire connecting layer is 1100 to 1350°C and the growth time is 1.5 to 4 hours; the volume ratio of the carbon source gas to the silicon source gas is 1:(2 to 4), and the volume of the dilution gas is 3 to 5 times the total volume of the carbon source gas and the silicon source gas; (4) Place intermediate product A in a deposition apparatus and introduce dilution gas, silicon source gas and carbon source gas to deposit a silicon carbide nanowire reinforced silicon carbide layer on intermediate product A to obtain intermediate product B; (5) A silicon carbide-zirconium carbide composite layer is deposited on the intermediate product B and post-processed to obtain intermediate product C; the silicon carbide-zirconium carbide composite layer is obtained by deposition using a two-phase gas introduction method, and the introduced gas is silicon tetrachloride, zirconium tetrachloride, carbon source gas and dilution gas, with a molar ratio of silicon tetrachloride and zirconium tetrachloride of 1:1; the post-processing operation is to place the carbonaceous material substrate in a heat treatment furnace covered with silicon powder for heat treatment at a temperature of 2000-2200℃ for 1-2 hours; (6) A zirconium carbide layer is deposited on the intermediate product C to obtain the coated carbonaceous material.

2. The method for preparing a coated carbonaceous material according to claim 1, characterized in that, The impregnation process in step (2) is as follows: the silicon-containing slurry is brushed onto the surface of the carbonaceous material substrate and impregnated by rotation at room temperature; the number of brushings is 3 to 5, and after each brushing, it is dried at room temperature for 2 to 10 minutes; the impregnation time is 1 to 3 hours, and the rotation speed is 10 to 30 revolutions.

3. The method for preparing a coated carbonaceous material according to claim 1, characterized in that, The deposition temperature of the silicon carbide nanowire-reinforced silicon carbide layer in step (4) is 1000-1400℃, and the deposition time is 5-20h.

4. The method for preparing a coated carbonaceous material according to any one of claims 1-3, characterized in that, The zirconium carbide layer in step (6) is prepared by high-temperature chemical vapor deposition, with a deposition temperature of 1700-1800℃ and a deposition time of 3-5h. The raw material gas is zirconium tetrachloride, the dilution gas is hydrogen, and the volume ratio of the raw material gas to the dilution gas is 1:

1.

5. A carbonaceous material with a coating, characterized in that, It is prepared by the preparation method according to any one of claims 1-4.