Preparation method of tantalum carbide coating graphite component

Abstract

The invention provides a preparation method of a tantalum carbide coating graphite component, and relates to the technical field of semiconductor growth. The surface of the graphite substrate is pre-coated with a titanium carbide coating through a low-temperature process method, and a buffer transition layer is obtained; the surface of the transition layer is coated with a titanium carbide coating through a variable-temperature process method, and temperature conversion is conducted; according to the variable-temperature process method, only one-time variable-temperature growth or multiple-cycle growth is carried out, a buffer layer with low crystal quality is pre-coated on the surface of a graphite substrate so as to reduce stress and thermal adaptation between the graphite substrate and a surface coating, and then a main coating tantalum carbide film is produced on the buffer layer through a variable-temperature process, so that the surface of the graphite substrate is coated with the tantalum carbide film. And a variable-temperature process is used for reducing the stress in the coating production process.

Description

Technical Field

[0001] The invention provides a method for preparing a tantalum carbide coated graphite component, and relates to the technical field of semiconductor growth, in particular to the technical field of preparing a tantalum carbide coated graphite component. Background Art

[0002] In the production process of third-generation semiconductors SiC and GaN, existing SiC-coated graphite discs and BN-coated graphite discs will chemically react with corrosive gases such as hydrogen and ammonia at high temperatures, causing the graphite materials to be exposed to the air during the production process. Impurities and corrosive gases in the graphite materials damage the graphite materials, thereby affecting the quality of crystal growth.

[0003] Tantalum carbide (TaC) ceramic is a material that can maintain good mechanical properties in ultra-high temperature environments above 3000°C. Its melting point can reach 3880°C. It has the characteristics of high specific strength, good oxidation resistance and ablation resistance. These characteristics can make the TaC coating still maintain a stable state in harsh semiconductor environments, and it is a coating material with great application prospects. However, the tantalum carbide TaC material itself has high hardness and brittleness. At the same time, the thermal expansion coefficient of TaC ceramics is very different from that of the graphite substrate, resulting in certain cracks between the graphite substrate and the coating surface unit cell, resulting in low bonding of the TaC coating, and even falling off, resulting in reduced strength, short life, and low practicality of the tantalum carbide coating. Therefore, the existing technology needs to be improved. Summary of the invention

[0004] The present invention provides a method for preparing a tantalum carbide coated graphite component, which is used to solve the problems in the prior art that the tantalum carbide TaC material itself has high hardness and brittleness, and the thermal expansion coefficient of the TaC ceramic is very different from that of the graphite substrate, resulting in huge thermal stress and lattice adaptation between the graphite substrate and the surface unit cell of the coating, resulting in low bonding of the TaC coating, or even shedding, thereby causing the tantalum carbide coating to have reduced strength, short life, low practicality, and the like:

[0005] The present invention provides a method for preparing a tantalum carbide coated graphite component, the method comprising:

[0006] S1. Preliminary treatment of the graphite substrate;

[0007] S2. Pre-coating a titanium carbide coating on the surface of the graphite substrate by a low-temperature process method to obtain a buffer transition layer;

[0008] S3, applying a titanium carbide coating to the surface of the transition layer by a temperature change process method to change the temperature;

[0009] S4. The variable temperature process method only performs variable temperature growth once or for multiple cycles.

[0010] Furthermore, the S1 includes:

[0011] The preset impurities on the surface of the graphite substrate are removed by heat treatment to obtain removal information;

[0012] The thermal expansion coefficient of the graphite substrate is 5-8×10-6 / K, the density is 1.7-1.9 g / cm3, and the total ash content is less than 10 ppm;

[0013] The graphite substrate is placed in a reaction chamber, the reaction chamber is evacuated, the reaction temperature is raised to 1000-1500° C., and hydrogen is introduced at a rate of 2-20 L / min for 5-30 minutes.

[0014] Further, the S2 includes:

[0015] A titanium carbide coating is pre-coated on the surface of a graphite substrate as a buffer transition layer by a low temperature process method;

[0016] The buffer transition layer is a titanium carbide coating with poor crystal quality.

[0017] Further, the S3 includes:

[0018] The prepared product is transformed from high temperature growth to bottom layer growth or from bottom layer growth to high temperature growth by a variable temperature process method to obtain transformation process data.

[0019] Furthermore, the preparation system comprises:

[0020] A preliminary processing module, used for performing preliminary processing on the graphite substrate;

[0021] A low-temperature buffer module is used to pre-coat a titanium carbide coating on the surface of a graphite substrate by a low-temperature process method to obtain a buffer transition layer;

[0022] A temperature conversion module is used to apply a titanium carbide coating to the surface of the transition layer through a temperature conversion process to perform temperature conversion;

[0023] The number setting module is used for the variable temperature process method to grow only once or for multiple cycles.

[0024] Furthermore, the preliminary processing module includes:

[0025] The preset impurities on the surface of the graphite substrate are removed by heat treatment to obtain removal information;

[0026] The thermal expansion coefficient of the graphite substrate is 5-8×10-6 / K, the density is 1.7-1.9 g / cm3, and the total ash content is less than 10 ppm;

[0027] The graphite substrate is placed in a reaction chamber, the reaction chamber is evacuated, the reaction temperature is raised to 1000-1500° C., and hydrogen is introduced at a rate of 2-20 L / min for 5-30 minutes.

[0028] Furthermore, the low temperature buffer module comprises:

[0029] A titanium carbide coating is pre-coated on the surface of a graphite substrate as a buffer transition layer by a low temperature process method;

[0030] The buffer transition layer is a titanium carbide coating with poor crystal quality.

[0031] Furthermore, the temperature conversion module comprises:

[0032] The prepared product is transformed from high temperature growth to bottom layer growth or from bottom layer growth to high temperature growth by a variable temperature process method to obtain transformation process data.

[0033] The beneficial effects of the present invention are as follows: a buffer layer with low crystal quality is pre-coated on the surface of the graphite substrate to reduce the stress and thermal adaptation between the graphite substrate and the surface coating, and then a main coating tantalum carbide film is produced on the buffer layer by a variable temperature process, and the variable temperature process is used to reduce the stress in the coating production process. By using the low-temperature pre-coating as a buffer layer, the lattice adaptation and thermal adaptation between the graphite substrate and the titanium carbide coating are effectively improved, and the stress between the coating and the substrate is reduced, thereby improving the bonding force and stability of the coating. The variable temperature process optimizes the growth conditions of the coating by adjusting the temperature and gas flow, reduces the stress and defects during the growth process, and improves the crystal quality and overall performance of the coating. The titanium carbide coating has high hardness and high temperature resistance, and can effectively protect the stability and service life of the graphite substrate in a high temperature environment. By optimizing the coating deposition process, the deposition efficiency and quality of the coating are improved, and the production cost and energy consumption are reduced. The graphite substrate after pre-treatment and coating deposition treatment has better high temperature resistance, wear resistance and corrosion resistance, and is suitable for applications in a wider range of high temperature, high pressure and corrosive environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A flow chart of the steps of the method for preparing a tantalum carbide coated graphite component provided by the present invention;

[0035] Figure 2 This is the XRD image of the tantalum carbide coated graphite component;

[0036] Figure 3 SEM image of a tantalum carbide coated graphite component. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0038] One embodiment of the present invention provides a method for preparing a tantalum carbide coated graphite component, the method comprising:

[0039] S1. Preliminary treatment of the graphite substrate;

[0040] S2. Pre-coating a titanium carbide coating on the surface of the graphite substrate by a low-temperature process method to obtain a buffer transition layer;

[0041] S3, applying a titanium carbide coating to the surface of the transition layer by a temperature change process method to change the temperature;

[0042] S4. The variable temperature process method only performs variable temperature growth once or for multiple cycles.

[0043] The working principle of the above technical solution is as follows: pretreatment of graphite substrate: remove impurities on the surface of the graphite substrate by heat treatment; pre-coat a titanium carbide coating with relatively poor crystal quality on the surface of the graphite substrate by low-temperature process, the coating temperature is 1500-1700℃, the hydrogen flow rate is 2-10L / min, the argon flow rate is 2-10L / min, and the thickness is 2-10um. On the surface of the transition layer, a titanium carbide coating is coated on the coating surface by a variable temperature process, gradually heating from 1700-1800℃ to 1900-2100℃, the hydrogen flow rate is 2-30L / min, the argon flow rate is 2-30L / min, and the thickness is 20-35um. The variable temperature process can only grow once or grow multiple cycles. Through the heat treatment process, high temperature is used to remove impurities on the surface of the graphite substrate, such as grease, oxides, etc., to ensure the cleanliness of the substrate surface and provide a good bonding surface for subsequent coating deposition. On the surface of the graphite substrate, a titanium carbide coating with relatively poor crystal quality is pre-coated by a low-temperature process. The purpose of this step is to act as a buffer layer, and to improve the lattice adaptation and thermal adaptation between the graphite substrate and the subsequent high-quality TiC coating through this layer of TiC coating with low crystal quality, thereby reducing the stress between the coating and the substrate. On the basis of the low-temperature pre-coating, a layer of high-quality TiC coating is deposited on the coating surface through a variable temperature process. In this process, the temperature is gradually increased from 1700-1800℃ to 1900-2100℃, and the flow rates of hydrogen and argon are controlled to optimize the growth conditions of the coating. The variable temperature process can be performed once or multiple times. By changing the temperature, the growth rate and crystal structure of the coating can be adjusted, thereby further reducing the stress and defects during the growth process and improving the overall quality of the coating. The graphite substrate is placed in the reaction chamber, evacuated to a vacuum, and then heated to 1000-1500℃, while hydrogen is introduced to further clean the substrate surface and promote uniform deposition of the coating.

[0044] Specific steps of the embodiment: S1. Pretreatment of the graphite substrate: removing impurities on the surface of the graphite substrate by heat treatment;

[0045] S2: A layer of titanium carbide coating with relatively poor crystal quality is pre-coated on the surface of the graphite substrate through a low-temperature process. The coating temperature is 1500-1700°C, the hydrogen flow rate is 2-10L / min, the argon flow rate is 2-10L / min, and the thickness is 2-10um.

[0046] S3: On the surface of the transition layer, a titanium carbide coating is applied on the coating surface through a variable temperature process, gradually increasing the temperature from 1700-1800°C to 1900-2100°C, with a hydrogen flow rate of 2-30L / min, an argon flow rate of 2-30L / min, and a thickness of 20-35um.

[0047] S4: The variable temperature process can be performed only once or for multiple cycles.

[0048] In one implementation, in S1, the thermal expansion coefficient of the graphite substrate is 5-8×10-6 / K, the density is 1.7-1.9 g / cm3, and the total ash content is less than 100 ppm.

[0049] The technical effects of the above technical scheme are as follows: by using the low-temperature pre-coating as a buffer layer, the lattice adaptation and thermal adaptation between the graphite substrate and the titanium carbide coating are effectively improved, and the stress between the coating and the substrate is reduced, thereby improving the bonding strength and stability of the coating. The variable temperature process optimizes the growth conditions of the coating by adjusting the temperature and gas flow, reduces the stress and defects during the growth process, and improves the crystal quality and overall performance of the coating. The titanium carbide coating has high hardness and high temperature resistance, and can effectively protect the stability and service life of the graphite substrate in a high temperature environment. By optimizing the coating deposition process, the deposition efficiency and quality of the coating are improved, and the production cost and energy consumption are reduced. The graphite substrate after pre-treatment and coating deposition has better high temperature resistance, wear resistance and corrosion resistance, and is suitable for a wider range of applications in high temperature, high pressure and corrosive environments.

[0050] In one embodiment of the present invention, the S1 includes:

[0051] The preset impurities on the surface of the graphite substrate are removed by heat treatment to obtain removal information;

[0052] The thermal expansion coefficient of the graphite substrate is 5-8×10-6 / K, the density is 1.7-1.9 g / cm3, and the total ash content is less than 10 ppm;

[0053] The graphite substrate is placed in a reaction chamber, the reaction chamber is evacuated, the reaction temperature is raised to 1000-1500° C., and hydrogen is introduced at a rate of 2-20 L / min for 5-30 minutes.

[0054] The working principle of the above technical solution is as follows: the heat treatment process mainly utilizes the difference in thermal stability between the impurities on the surface of the graphite substrate and the substrate material under high temperature environment, and heats the impurities to undergo physical or chemical changes, such as evaporation, oxidation, reduction, etc., so as to achieve the purpose of removing impurities. These impurities may include grease, moisture, oxides, residual processing aids or other contaminants, which will affect the bonding strength of the subsequent coating with the graphite substrate and the overall performance of the coating. The thermal expansion coefficient of the graphite substrate indicates the degree of its dimensional change when the temperature changes. This characteristic is crucial for the matching and stress control of the coating and the substrate. The density reflects the compactness and quality of the graphite substrate, and also has a certain effect on the adhesion and overall performance of the coating. The total ash content of less than 10ppm indicates that the content of non-graphite components in the graphite substrate is extremely low, which helps to reduce impurities and defects in the coating. Placing the graphite substrate in the reaction chamber and evacuating it to a vacuum is to remove oxygen and other gases in the reaction chamber to prevent them from reacting with the graphite substrate or coating at high temperature and affecting the coating quality. Raising the reaction temperature to 1000-1500℃ is to further clean the surface of the graphite substrate, remove residual impurities, and promote the bonding of the subsequent coating with the substrate. The purpose of introducing 2 to 20 L / min of hydrogen is to create a reducing atmosphere, which helps to remove oxides on the surface of the graphite substrate and may promote the chemical bonding between the coating and the substrate.

[0055] The technical effect of the above technical solution is: by heat treatment, impurities on the surface of the graphite substrate are removed, the interface barrier between the coating and the substrate is reduced, and the bonding force and adhesion of the coating are improved. The vacuum treatment and high-temperature hydrogen atmosphere in the reaction chamber help to further clean the graphite substrate, reduce impurities and defects in the coating, and thus improve the overall performance of the coating, such as hardness, wear resistance, corrosion resistance, etc. Through heat treatment, the microstructure and chemical properties of the surface of the graphite substrate are improved, which helps to enhance its stability in harsh environments such as high temperature and high pressure. Placing the graphite substrate in the reaction chamber for centralized treatment can achieve simultaneous processing of multiple graphite substrates, thereby improving production efficiency. By optimizing the heat treatment process and reaction chamber conditions, energy consumption and scrap rate can be reduced, thereby reducing production costs.

[0056] In one embodiment of the present invention, S2 includes:

[0057] A titanium carbide coating is pre-coated on the surface of a graphite substrate as a buffer transition layer by a low temperature process method;

[0058] The buffer transition layer is a titanium carbide coating with poor crystal quality.

[0059] The working principle of the above technical solution is: a low-temperature process is used to pre-coat a titanium carbide coating with relatively poor crystal quality as a buffer layer to improve the lattice adaptation and thermal adaptation between the graphite substrate and the titanium carbide coating and reduce stress. Low-temperature process refers to the coating deposition process carried out at a relatively low temperature. This temperature range is selected to avoid significant deformation or damage of the graphite substrate at high temperature, while ensuring that the titanium carbide coating can be uniformly deposited on the surface of the graphite substrate. By adjusting the process parameters (such as temperature, gas flow, deposition time, etc.) during the deposition process, the crystal quality of the titanium carbide coating can be intentionally controlled. In this case, the pre-coated titanium carbide coating is designed to have poor crystal quality, and there are more defects, grain boundaries or amorphous regions in the crystal structure of the coating. The titanium carbide coating with poor crystal quality serves as a buffer transition layer, and its main function is to improve the lattice adaptation and thermal adaptation between the graphite substrate and the subsequent high-quality titanium carbide coating. Due to the differences in the crystal structure and thermal expansion coefficient of graphite and titanium carbide, direct deposition of high-quality titanium carbide coatings may result in greater stress and interface mismatch. The buffer layer with poorer crystal quality can "absorb" these mismatches, thereby reducing the stress between the coating and the substrate and improving the stability and adhesion of the coating.

[0060] The technical effect of the above technical solution is: by pre-coating a titanium carbide coating with poor crystal quality as a buffer transition layer, the interfacial bonding force between the graphite substrate and the subsequent coating can be effectively improved, and the adhesion and stability of the coating can be improved. The presence of the buffer transition layer helps to reduce stress and defects during the growth of the coating, thereby improving the overall performance of the coating, such as hardness, wear resistance, corrosion resistance, etc. By introducing a buffer transition layer, the graphite substrate can better adapt to the use requirements in harsh environments such as high temperature and high pressure, and extend the service life of the graphite substrate. Due to the difference in thermal expansion coefficients between graphite and titanium carbide, direct deposition of high-quality titanium carbide coatings may cause cracking of the coating. The introduction of a buffer transition layer can effectively reduce this cracking risk. By adjusting the crystal quality and thickness of the buffer transition layer, the compatibility between the coating and the substrate can be further optimized, and the flexibility and controllability of coating preparation can be improved.

[0061] In one embodiment of the present invention, S3 includes:

[0062] The prepared product is transformed from high temperature growth to bottom layer growth or from bottom layer growth to high temperature growth by a variable temperature process method to obtain transformation process data.

[0063] The working principle of the above technical solution is: by using a variable temperature process, it can be transformed from high temperature to bottom layer growth, or from bottom layer growth to high temperature growth. The main purpose is to reduce stress and defects in the growth process through temperature change; the core of the variable temperature process lies in the precise control of the deposition temperature. By adjusting the temperature during the deposition process, the transformation from high temperature to low temperature or from low temperature to high temperature can be achieved. This transformation can be one-time or multiple cycles. The growth mechanism of titanium carbide (or other deposited materials) will be different in different temperature ranges. At high temperatures, the migration rate of atoms or molecules increases, which is conducive to the formation of dense and well-crystallized coatings; while at low temperatures, the growth rate may be slower, but it helps to reduce defects and stress in the coating. During the variable temperature process, as the temperature changes, the interface adaptability between the coating and the substrate will also change. Through reasonable temperature changes, the lattice adaptability and thermal adaptability between the coating and the substrate can be optimized, thereby reducing stress and defects inside the coating. The variable temperature process can also be used to regulate the composition distribution and microstructure in the coating. For example, at high temperature, certain elements may be more easily reduced or evaporated, thus affecting the composition of the coating; whereas at low temperature, it may be more conducive to the formation of a specific microstructure.

[0064] The technical effect of the above technical solution is: through the variable temperature process, the coating growth process can be precisely controlled to obtain a coating with excellent performance. This coating may have higher hardness, better wear resistance and corrosion resistance. The variable temperature process helps to reduce stress and defects inside the coating, thereby improving the stability and service life of the coating. Especially when there is a large difference in thermal expansion coefficient between the coating and the substrate, the effect of the variable temperature process is particularly significant. By optimizing the interface adaptability between the coating and the substrate, the variable temperature process can improve the bonding force between the coating and the substrate and prevent the coating from falling off or peeling off during use. The variable temperature process can flexibly adjust the growth conditions and structural characteristics of the coating according to different application requirements, thereby enhancing the adaptability of the coating to different environments. In the process of variable temperature, by collecting and analyzing the transformation process data (such as temperature curves, growth rates, composition changes, etc.), it can provide strong data support for further optimizing the coating preparation process.

[0065] In one embodiment of the present invention, the preparation system comprises:

[0066] A preliminary processing module, used for performing preliminary processing on the graphite substrate;

[0067] A low-temperature buffer module is used to pre-coat a titanium carbide coating on the surface of a graphite substrate by a low-temperature process method to obtain a buffer transition layer;

[0068] A temperature conversion module is used to apply a titanium carbide coating to the surface of the transition layer through a temperature conversion process to perform temperature conversion;

[0069] The number setting module is used for the variable temperature process method to grow only once or for multiple cycles.

[0070] The working principle of the above technical solution is: through the heat treatment process, high temperature is used to remove impurities on the surface of the graphite substrate, such as grease, oxides, etc., to ensure the cleanliness of the substrate surface and provide a good bonding surface for subsequent coating deposition. On the surface of the graphite substrate, a layer of titanium carbide (TiC) coating with relatively poor crystal quality is pre-coated by a low-temperature process. The purpose of this step is to serve as a buffer layer, and to improve the lattice adaptation and thermal adaptation between the graphite substrate and the subsequent high-quality TiC coating through this layer of TiC coating with low crystal quality, thereby reducing the stress between the coating and the substrate. On the basis of the low-temperature pre-coating, a layer of high-quality TiC coating is deposited on the coating surface through a variable temperature process. In this process, the temperature is gradually increased from 1700-1800°C to 1900-2100°C, and the flow rates of hydrogen and argon are controlled at the same time to optimize the growth conditions of the coating. The variable temperature process can be performed once or multiple times. By changing the temperature, the growth rate and crystal structure of the coating can be adjusted, thereby further reducing the stress and defects during the growth process and improving the overall quality of the coating. The graphite substrate is placed in a reaction chamber, evacuated to a vacuum and then heated to 1000-1500°C, while hydrogen is introduced to further clean the substrate surface and promote uniform deposition of the coating.

[0071] The technical effects of the above technical scheme are as follows: by using the low-temperature pre-coating as a buffer layer, the lattice adaptation and thermal adaptation between the graphite substrate and the titanium carbide coating are effectively improved, and the stress between the coating and the substrate is reduced, thereby improving the bonding strength and stability of the coating. The variable temperature process optimizes the growth conditions of the coating by adjusting the temperature and gas flow, reduces the stress and defects during the growth process, and improves the crystal quality and overall performance of the coating. The titanium carbide coating has high hardness and high temperature resistance, and can effectively protect the stability and service life of the graphite substrate in a high temperature environment. By optimizing the coating deposition process, the deposition efficiency and quality of the coating are improved, and the production cost and energy consumption are reduced. The graphite substrate after pre-treatment and coating deposition has better high temperature resistance, wear resistance and corrosion resistance, and is suitable for a wider range of applications in high temperature, high pressure and corrosive environments.

[0072] In one embodiment of the present invention, the preliminary processing module includes:

[0073] The preset impurities on the surface of the graphite substrate are removed by heat treatment to obtain removal information;

[0074] The thermal expansion coefficient of the graphite substrate is 5-8×10-6 / K, the density is 1.7-1.9 g / cm3, and the total ash content is less than 10 ppm;

[0075] The graphite substrate is placed in a reaction chamber, the reaction chamber is evacuated, the reaction temperature is raised to 1000-1500° C., and hydrogen is introduced at a rate of 2-20 L / min for 5-30 minutes.

[0076] The working principle of the above technical solution is as follows: the heat treatment process mainly utilizes the difference in thermal stability between the impurities on the surface of the graphite substrate and the substrate material under high temperature environment, and heats the impurities to undergo physical or chemical changes, such as evaporation, oxidation, reduction, etc., so as to achieve the purpose of removing impurities. These impurities may include grease, moisture, oxides, residual processing aids or other contaminants, which will affect the bonding strength of the subsequent coating with the graphite substrate and the overall performance of the coating. The thermal expansion coefficient of the graphite substrate indicates the degree of its dimensional change when the temperature changes. This characteristic is crucial for the matching and stress control of the coating and the substrate. The density reflects the compactness and quality of the graphite substrate, and also has a certain effect on the adhesion and overall performance of the coating. The total ash content of less than 10ppm indicates that the content of non-graphite components in the graphite substrate is extremely low, which helps to reduce impurities and defects in the coating. Placing the graphite substrate in the reaction chamber and evacuating it to a vacuum is to remove oxygen and other gases in the reaction chamber to prevent them from reacting with the graphite substrate or coating at high temperature and affecting the coating quality. Raising the reaction temperature to 1000-1500℃ is to further clean the surface of the graphite substrate, remove residual impurities, and promote the bonding of the subsequent coating with the substrate. The purpose of introducing 2 to 20 L / min of hydrogen is to create a reducing atmosphere, which helps to remove oxides on the surface of the graphite substrate and may promote the chemical bonding between the coating and the substrate.

[0077] The technical effect of the above technical solution is: by heat treatment, impurities on the surface of the graphite substrate are removed, the interface barrier between the coating and the substrate is reduced, and the bonding force and adhesion of the coating are improved. The vacuum treatment and high-temperature hydrogen atmosphere in the reaction chamber help to further clean the graphite substrate, reduce impurities and defects in the coating, and thus improve the overall performance of the coating, such as hardness, wear resistance, corrosion resistance, etc. Through heat treatment, the microstructure and chemical properties of the surface of the graphite substrate are improved, which helps to enhance its stability in harsh environments such as high temperature and high pressure. Placing the graphite substrate in the reaction chamber for centralized treatment can achieve simultaneous processing of multiple graphite substrates, thereby improving production efficiency. By optimizing the heat treatment process and reaction chamber conditions, energy consumption and scrap rate can be reduced, thereby reducing production costs.

[0078] In one embodiment of the present invention, the low temperature buffer module comprises:

[0079] A titanium carbide coating is pre-coated on the surface of a graphite substrate as a buffer transition layer by a low temperature process method;

[0080] The buffer transition layer is a titanium carbide coating with poor crystal quality.

[0081] The working principle of the above technical solution is as follows: low temperature process refers to the coating deposition process carried out at a relatively low temperature. This temperature range is selected to avoid significant deformation or damage of the graphite substrate at high temperature, while ensuring that the titanium carbide coating can be uniformly deposited on the surface of the graphite substrate. The crystal quality of the titanium carbide coating can be intentionally controlled by adjusting the process parameters (such as temperature, gas flow, deposition time, etc.) during the deposition process. In this case, the pre-coated titanium carbide coating is designed to have poor crystal quality, and there are more defects, grain boundaries or amorphous regions in the crystal structure of the coating. The titanium carbide coating with poor crystal quality serves as a buffer transition layer, and its main function is to improve the lattice adaptability and thermal adaptability between the graphite substrate and the subsequent high-quality titanium carbide coating. Due to the differences in the crystal structure and thermal expansion coefficient of graphite and titanium carbide, the direct deposition of high-quality titanium carbide coating may cause large stress and interface mismatch. The buffer layer with poor crystal quality can "absorb" these mismatches, thereby reducing the stress between the coating and the substrate and improving the stability and adhesion of the coating.

[0082] The technical effect of the above technical solution is: by pre-coating a titanium carbide coating with poor crystal quality as a buffer transition layer, the interfacial bonding force between the graphite substrate and the subsequent coating can be effectively improved, and the adhesion and stability of the coating can be improved. The presence of the buffer transition layer helps to reduce stress and defects during the growth of the coating, thereby improving the overall performance of the coating, such as hardness, wear resistance, corrosion resistance, etc. By introducing a buffer transition layer, the graphite substrate can better adapt to the use requirements in harsh environments such as high temperature and high pressure, and extend the service life of the graphite substrate. Due to the difference in thermal expansion coefficients between graphite and titanium carbide, direct deposition of high-quality titanium carbide coatings may cause cracking of the coating. The introduction of a buffer transition layer can effectively reduce this cracking risk. By adjusting the crystal quality and thickness of the buffer transition layer, the compatibility between the coating and the substrate can be further optimized, and the flexibility and controllability of coating preparation can be improved.

[0083] In one embodiment of the present invention, the temperature conversion module comprises:

[0084] The prepared product is transformed from high temperature growth to bottom layer growth or from bottom layer growth to high temperature growth by a variable temperature process method to obtain transformation process data.

[0085] The working principle of the above technical solution is as follows: the core of the variable temperature process lies in the precise control of the deposition temperature. By adjusting the temperature during the deposition process, the transformation from high temperature to low temperature or from low temperature to high temperature can be achieved. This transformation can be one-time or multiple cycles. The growth mechanism of titanium carbide (or other deposited materials) will be different in different temperature ranges. At high temperatures, the migration rate of atoms or molecules increases, which is conducive to the formation of a dense, well-crystallized coating; while at low temperatures, the growth rate may be slower, but it helps to reduce defects and stress in the coating. During the variable temperature process, as the temperature changes, the interface adaptability between the coating and the substrate will also change. Through reasonable temperature changes, the lattice adaptability and thermal adaptability between the coating and the substrate can be optimized, thereby reducing the stress and defects inside the coating. The variable temperature process can also be used to regulate the composition distribution and microstructure in the coating. For example, in the high temperature stage, some elements may be more easily reduced or evaporated, thereby affecting the composition of the coating; while in the low temperature stage, it may be more conducive to the formation of a specific microstructure.

[0086] The technical effect of the above technical solution is: through the variable temperature process, the coating growth process can be precisely controlled to obtain a coating with excellent performance. This coating may have higher hardness, better wear resistance and corrosion resistance. The variable temperature process helps to reduce stress and defects inside the coating, thereby improving the stability and service life of the coating. Especially when there is a large difference in thermal expansion coefficient between the coating and the substrate, the effect of the variable temperature process is particularly significant. By optimizing the interface adaptability between the coating and the substrate, the variable temperature process can improve the bonding force between the coating and the substrate and prevent the coating from falling off or peeling off during use. The variable temperature process can flexibly adjust the growth conditions and structural characteristics of the coating according to different application requirements, thereby enhancing the adaptability of the coating to different environments. In the process of variable temperature, by collecting and analyzing the transformation process data (such as temperature curves, growth rates, composition changes, etc.), it can provide strong data support for further optimizing the coating preparation process.

[0087] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing a tantalum carbide coated graphite component, characterized in that: The preparation method comprises: S1. Preliminary treatment of the graphite substrate; S2. Pre-coating a titanium carbide coating on the surface of the graphite substrate by a low-temperature process method to obtain a buffer transition layer; S3, applying a titanium carbide coating to the surface of the transition layer by a temperature change process method to change the temperature; S4. The variable temperature process method only performs variable temperature growth once or for multiple cycles.

2. The method for preparing a tantalum carbide coated graphite component according to claim 1, characterized in that: The S1 includes: The preset impurities on the surface of the graphite substrate are removed by heat treatment to obtain removal information; The thermal expansion coefficient of the graphite substrate is 5-8×10-6 / K, the density is 1.7-1.9 g / cm3, and the total ash content is less than 10 ppm; The graphite substrate is placed in a reaction chamber, the reaction chamber is evacuated, the reaction temperature is raised to 1000-1500° C., and hydrogen is introduced at a rate of 2-20 L / min for 5-30 minutes.

3. The method for preparing a tantalum carbide coated graphite component according to claim 1, characterized in that: The S2 includes: A titanium carbide coating is pre-coated on the surface of a graphite substrate as a buffer transition layer by a low temperature process method; The buffer transition layer is a titanium carbide coating with a preset poor crystal quality range.

4. The method for preparing a tantalum carbide coated graphite component according to claim 1, characterized in that: The S3 includes: The prepared product is transformed from high temperature growth to bottom layer growth or from bottom layer growth to high temperature growth by a variable temperature process method to obtain transformation process data.

5. A preparation system for implementing the method for preparing a tantalum carbide coated graphite component as claimed in claim 1, characterized in that: The preparation system comprises: A preliminary processing module, used for performing preliminary processing on the graphite substrate; A low-temperature buffer module is used to pre-coat a titanium carbide coating on the surface of a graphite substrate by a low-temperature process method to obtain a buffer transition layer; A temperature conversion module is used to apply a titanium carbide coating to the surface of the transition layer through a temperature conversion process to perform temperature conversion; The number setting module is used for the variable temperature process method to grow only once or for multiple cycles.

6. A preparation system for a method for preparing a tantalum carbide coated graphite component according to claim 5, characterized in that: The preliminary processing module comprises: The preset impurities on the surface of the graphite substrate are removed by heat treatment to obtain removal information; The thermal expansion coefficient of the graphite substrate is 5-8×10-6 / K, the density is 1.7-1.9 g / cm3, and the total ash content is less than 10 ppm; The graphite substrate is placed in a reaction chamber, the reaction chamber is evacuated, the reaction temperature is raised to 1000-1500° C., and hydrogen is introduced at a rate of 2-20 L / min for 5-30 minutes.

7. A preparation system for a method for preparing a tantalum carbide coated graphite component according to claim 5, characterized in that: The low temperature buffer module comprises: A titanium carbide coating is pre-coated on the surface of a graphite substrate as a buffer transition layer by a low temperature process method; The buffer transition layer is a titanium carbide coating with a preset poor crystal quality range.

8. A preparation system for a method for preparing a tantalum carbide coated graphite component according to claim 5, characterized in that: The temperature conversion module comprises: The prepared product is transformed from high temperature growth to bottom layer growth or from bottom layer growth to high temperature growth by a variable temperature process method to obtain transformation process data.

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