Composite carbon material and method for producing the same

Abstract

The application provides a composite carbon material and a preparation method thereof, and the preparation method at least comprises the following steps: providing a carbon base; mixing a tantalum-containing compound with an organic solvent to obtain a tantalum-containing slurry; uniformly covering the tantalum-containing slurry on the surface of the carbon base to obtain a reaction layer on the carbon base; uniformly covering tantalum powder on the reaction layer to obtain a tantalum metal coating layer on the reaction layer; heating the carbon base with the tantalum metal coating layer to a preset temperature under a vacuum state, and keeping the temperature for a preset time; and cooling the heated carbon base to room temperature to obtain the composite carbon material. Through the composite carbon material and the preparation method thereof, the compactness and quality of the tantalum carbide coating layer can be improved.

Description

Technical Field

[0001] This invention relates to the field of materials preparation, and in particular to a composite carbon material and its preparation method. Background Technology

[0002] Tantalum carbide, a transition metal carbide, is insoluble in water, slightly soluble in sulfuric acid and hydrofluoric acid, and soluble in hydrofluoric acid and nitric acid. It has excellent properties such as chemical stability, high melting point, high hardness, good electrical conductivity and thermal shock resistance, high bending strength, and low coefficient of thermal expansion. It is often used as an additive or coating material.

[0003] In semiconductor material processing, tantalum carbide coatings provide excellent protection for the carbon substrate in demanding semiconductor manufacturing processes. Tantalum carbide coatings significantly extend the lifespan of the carbon substrate, maintain reaction stoichiometry, and suppress impurity migration into epitaxial and crystal growth applications, thus improving yield and quality. Furthermore, tantalum carbide coatings can protect critical furnaces and reaction components from the effects of hot ammonia, hydrogen and silicon vapors, and molten metal at high temperatures (up to 2200°C). Therefore, the preparation of tantalum carbide coatings on carbon substrates has significant application value. However, current methods for preparing tantalum carbide coatings on carbon substrates suffer from problems such as non-dense coatings, unstable coating quality, cumbersome preparation processes, and high costs. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a composite carbon material and its preparation method, which can prepare a dense and stable tantalum carbide coating on the surface of a carbon matrix, extend the service life of the carbon matrix, and reduce the preparation cost.

[0005] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution.

[0006] This invention provides a method for preparing a composite carbon material, comprising at least the following steps:

[0007] Provide a one-carbon matrix;

[0008] A tantalum-containing compound is mixed with an organic solvent to obtain a tantalum-containing slurry;

[0009] The tantalum-containing slurry is uniformly coated on the surface of the carbon matrix to obtain a reaction layer on the carbon matrix;

[0010] Tantalum powder is uniformly covered on the reaction layer to obtain a tantalum metal coating on the reaction layer;

[0011] Under vacuum, the carbon substrate with the tantalum metal coating is heated to a preset temperature and held at that temperature for a preset time; and

[0012] The heated carbon matrix was cooled to room temperature to obtain a composite carbon material.

[0013] In one embodiment of the present invention, the tantalum-containing compound includes at least one of tantalum oxide, tantalum halide, and tantalum alkoxide.

[0014] In one embodiment of the present invention, the organic solvent includes at least one selected from ethanol, acetylacetone, benzene, toluene, and tetrahydrofuran.

[0015] In one embodiment of the present invention, the mass ratio of the tantalum-containing compound to the organic solvent is 1:(1-5).

[0016] In one embodiment of the present invention, the method of uniformly covering the surface of the carbon matrix with the tantalum-containing slurry includes either immersion or coating.

[0017] In one embodiment of the present invention, the method of uniformly covering the reaction layer with tantalum powder includes any one of plasma spraying, laser cladding or heating.

[0018] In one embodiment of the present invention, the preset temperature is 2100-2400℃ and the preset time is 5-20h.

[0019] In one embodiment of the present invention, the tantalum powder has a particle size of 50-500 mesh, and the tantalum powder has a tantalum mass content greater than or equal to 99.50% and an oxygen mass content less than or equal to 0.40%.

[0020] The present invention also proposes a composite carbon material obtained by any of the preparation methods described above, comprising at least:

[0021] Carbon matrix;

[0022] A tantalum carbide coating is disposed on the surface of the carbon substrate; and

[0023] A tantalum metal coating is disposed on the tantalum carbide coating.

[0024] In one embodiment of the present invention, the thickness of the tantalum carbide coating is 0.1-1 mm.

[0025] In summary, this invention provides a composite carbon material and its preparation method. By forming a tantalum carbide coating on the surface of a carbon matrix, the carbon matrix can be effectively protected, avoiding corrosion from fumed silicon and extending the service life of the carbon matrix. Furthermore, the process is convenient and the preparation cost is low. Moreover, the tantalum metal coating on the outer side of the tantalum carbide coating can repair and fill pores and cracks in the tantalum carbide coating, making the tantalum carbide coating formed on the carbon matrix surface denser and more stable in quality.

[0026] Of course, implementing any of the methods of this invention does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic flowchart of the method for preparing tantalum carbide coating on a carbon substrate provided by the present invention.

[0029] Figure 2 This is a schematic diagram of the structure for preparing a tantalum carbide coating on a carbon substrate using the method of the present invention.

[0030] Label Explanation:

[0031] 100, carbon matrix; 200, reaction layer; 300, tantalum metal coating. Detailed Implementation

[0032] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0033] It should be understood that the invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0034] The technical solution of the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Tantalum carbide has a high melting point (3880℃), high hardness (Mohs hardness 9-10), and a relatively high thermal conductivity (22 W·m). -1 ·K -1 It has a relatively high flexural strength (340-400MPa) and a relatively low coefficient of thermal expansion (6.6×10⁻⁶). -6 K -1Tantalum carbide exhibits excellent thermochemical stability and superior physical properties. Furthermore, it possesses good chemical and mechanical compatibility with carbon-based materials, making it suitable as a coating for crystal growth equipment. This coating enhances the equipment's oxidation resistance, corrosion resistance, wear resistance, and mechanical properties, thereby improving crystal quality. The composite carbon material and its preparation method provided by this invention enable the formation of a high-quality tantalum carbide coating on the carbon matrix surface, effectively protecting the carbon matrix, preventing corrosion from fumed silicon, and extending the service life of the carbon matrix. Moreover, the tantalum metal coating on the outer side of the tantalum carbide coating can repair the coating, improving its density and quality, thus better protecting the carbon matrix.

[0036] Please see Figure 1 As shown, the present invention provides a method for preparing a composite carbon material, which includes at least steps S11-S16.

[0037] S11 provides a carbon matrix.

[0038] S12. Mix the tantalum-containing compound with an organic solvent to obtain a tantalum-containing slurry.

[0039] S13. The tantalum-containing slurry is uniformly coated on the surface of the carbon substrate to obtain a reaction layer on the carbon substrate.

[0040] S14. Tantalum powder is evenly coated on the reaction layer to obtain a tantalum metal coating.

[0041] S15. Under vacuum conditions, heat the carbon substrate with tantalum metal coating to a preset temperature and hold it at that temperature for a preset time.

[0042] S16. Cool the heated carbon matrix to room temperature to obtain the composite carbon material.

[0043] Please see Figures 1 to 2 As shown, in one embodiment of the present invention, in step S11, the carbon substrate 100 is, for example, a graphite component. Further, the surface of the carbon substrate 100 is pretreated before use to remove impurities, ensuring a tight bond between the carbon substrate 100 and the subsequently formed reaction layer 200. In one embodiment of the present invention, the pretreatment includes, for example, sanding the surface of the carbon substrate 100 with sandpaper, then cleaning it in an ultrasonic cleaning device, followed by drying it in an oven. In one embodiment of the present invention, the ultrasonic cleaning fluid used in the ultrasonic cleaning process includes, for example, one or more of acetone, ethanol, or acetonitrile, and the ultrasonic time is, for example, 5-60 minutes.

[0044] Please see Figure 1As shown, in one embodiment of the present invention, in step S12, a tantalum-containing compound is mixed with an organic solvent to obtain a tantalum-containing slurry. The tantalum-containing compound includes, for example, at least one of tantalum oxide, tantalum halide, and tantalum alkoxide, and the organic solvent includes, for example, at least one of ethanol, acetylacetone, benzene, toluene, and tetrahydrofuran. The mass ratio of the tantalum-containing compound to the organic solvent is, for example, 1:(1-5).

[0045] Please see Figures 1 to 2 As shown, in one embodiment of the present invention, in step S13, a tantalum-containing slurry is uniformly coated onto the surface of a carbon substrate 100, thereby forming a reaction layer 200 on the carbon substrate 100. The method of uniformly coating the surface of the carbon substrate 100 with the tantalum-containing slurry includes, for example, either immersion or coating. Specifically, when using the immersion method, the carbon substrate 100 is immersed in the tantalum-containing slurry for, for example, 2 hours to 10 hours. When using the coating method, the tantalum-containing slurry is uniformly coated onto the surface of the carbon substrate 100 by, for example, drop coating or spray coating.

[0046] Please see Figures 1 to 2 As shown, in one embodiment of the present invention, in step S14, tantalum powder is uniformly coated onto the reaction layer 200, resulting in a tantalum metal coating 300 on the reaction layer 200. The tantalum powder has a particle size of, for example, 50-500 mesh, a tantalum mass content of, for example, greater than or equal to 99.50%, and an oxygen mass content of, for example, less than or equal to 0.40%. The tantalum powder may also include other impurities, such as one or more of carbon, hydrogen, and nitrogen. The method of uniformly coating the reaction layer 200 with tantalum powder includes, for example, any one of plasma spraying, laser cladding, or heating. In this embodiment, for example, plasma spraying is used to uniformly coat the reaction layer 200 with tantalum powder, improving the adhesion between the tantalum metal coating 300 and the reaction layer 200, while also improving the wear resistance, corrosion resistance, and heat resistance of the carbon substrate 100. In plasma spraying, the main gas is, for example, argon, the auxiliary gas is, for example, hydrogen or nitrogen, the arc voltage is, for example, 20-80V, the arc current is, for example, 500-700A, the spray distance is, for example, 50-200mm, and the tantalum powder feeding rate is, for example, 10-40g / min.

[0047] Please see Figures 1 to 2As shown, in one embodiment of the present invention, in step S14, after tantalum powder is heated to a molten state, it impacts the carbon matrix 100 at high speed, forming a layered tantalum metal coating 300 on the reaction layer 200. The tantalum metal coating 300 is firmly attached to the reaction layer 200. The bonding method between the tantalum metal coating 300 and the reaction layer 200 includes at least one of mechanical bonding, physical bonding, and metallurgical bonding. In this embodiment, the bonding method between the tantalum metal coating 300 and the reaction layer 200 is primarily mechanical bonding, but physical bonding and metallurgical bonding may also occur between parts of the tantalum metal coating 300 and parts of the reaction layer 200.

[0048] Please see Figures 1 to 2 As shown, in one embodiment of the present invention, in step S15, the carbon substrate 100 with the tantalum metal coating 300 is heated to a preset temperature under vacuum and held at that temperature for a preset time. The preset temperature is, for example, 2100-2400℃, and the preset time is 5-20 hours. The container holding the carbon substrate 100 includes, for example, any one of a reaction vessel, a tube furnace, a sintering furnace, or a heating furnace. In this embodiment, when the carbon substrate 100 is heated, the tantalum-containing compound in the reaction layer 200, such as tantalum oxide, undergoes a redox reaction with the carbon on the surface of the carbon substrate 100, i.e., Ta₂O₅ + 7C = 2TaC + 5CO. The reaction layer 200 is transformed into a tantalum carbide coating, which adheres to the carbon substrate 100. Furthermore, the tantalum metal coating 300 is attached to the reaction layer 200 as a protective layer, covering the reaction layer 200 and preventing it from detaching from the carbon substrate 100. This reduces the amount of reaction layer 200 lost. At the same time, the tantalum metal coating 300 can also serve as a thermal barrier layer, repairing the tantalum carbide coating produced by the reaction of the reaction layer 200 and filling any pores or cracks in the tantalum carbide coating, thereby improving the density and quality of the tantalum carbide coating.

[0049] Please see Figures 1 to 2 As shown, in one embodiment of the present invention, in step S16, the heated carbon matrix 100 is cooled to room temperature to obtain a composite carbon material. By cooling the carbon matrix 100 and the tantalum carbide coating on the carbon matrix 100, thermal stress and structural stress can be eliminated, and cracking of the tantalum carbide coating can be avoided.

[0050] Please see Figures 1 to 2As shown, the present invention also provides a composite carbon material obtained by the above-described method for preparing composite carbon materials. The composite carbon material includes, for example, a carbon substrate 100, a tantalum carbide coating, and a tantalum metal coating 300. The tantalum carbide coating is disposed on the surface of the carbon substrate 100, and the tantalum metal coating 300 is disposed on the tantalum carbide coating. In one embodiment of the present invention, the thickness of the tantalum carbide coating is, for example, 0.1-1 mm, or more specifically, 0.2 mm, 0.4 mm, or 0.6 mm, and the thickness of the tantalum metal coating 300 is, for example, 0.1-1 mm, or more specifically, 0.1 mm, 0.5 mm, or 1 mm. The tantalum carbide coating on the composite carbon material provided by the present invention can effectively protect the carbon substrate 100, prevent corrosion by fumed silicon, and extend the service life of the carbon substrate 100. Furthermore, the composite carbon material provided by the present invention has a tantalum metal coating 300 on the tantalum carbide coating. During the formation of the tantalum carbide coating, the tantalum metal coating 300 can repair and fill the pores or cracks in the tantalum carbide coating, so that a denser and more stable tantalum carbide coating can be formed on the surface of the carbon substrate 100.

[0051] The technical solution of the present invention will be described in detail below through several specific embodiments. Unless otherwise stated, the raw materials and reagents used in the following embodiments are all commercially available products, or can be prepared by conventional methods in the art, and the instruments used in the embodiments are all commercially available.

[0052] Example 1

[0053] A graphite part is provided. After sanding the surface of the graphite part with sandpaper, it is ultrasonically cleaned with ethanol in an ultrasonic cleaning device for 20 minutes, and then dried in an oven. Tantalum oxide and tetrahydrofuran are mixed evenly at a mass ratio of 1:1.5 to obtain a tantalum-containing slurry. The tantalum-containing slurry is uniformly coated on the surface of the graphite part to obtain a reaction layer. 140-mesh tantalum powder is sprayed onto the reaction layer by plasma spraying to obtain a tantalum metal coating. The main gas of plasma spraying is argon, the auxiliary gas is hydrogen, the arc voltage is 50V, the arc current is 600A, the spray distance is 130mm, and the powder feeding rate is 26g / min. The graphite part with the tantalum metal coating is placed in a sintering furnace, and the sintering furnace is evacuated to below 1Pa. Then, the graphite part is heated to 2300℃ and held at that temperature for 10 hours. After cooling the graphite part to room temperature, the graphite part is removed to obtain a composite carbon material.

[0054] Example 2

[0055] The difference between this embodiment and Embodiment 1 is that the mass ratio of tantalum oxide to tetrahydrofuran is 1:1.2, and the holding time of the graphite part in the sintering furnace is 8 hours; the rest are the same.

[0056] Comparative Example 1

[0057] A graphite part was taken, and its surface was sanded with sandpaper. It was then ultrasonically cleaned with ethanol for 20 minutes and subsequently dried in an oven. Acetylacetone and tantalum chloride were mixed at a molar ratio of 1:1 to obtain a mixed solution. This solution was heated to 200℃ and reacted for 12 hours to obtain tantalum carbide slurry. The tantalum carbide slurry had a nearly spherical particle morphology with a particle size of approximately 1 μm and a BET specific surface area of ​​121.9 m². 2 / g. After uniformly coating the surface of the graphite part with tantalum carbide slurry, the graphite part is placed in a sintering furnace. Under vacuum, the graphite part is heated to 2000℃ and held for 1 hour. After cooling the graphite part to room temperature, the graphite part is removed to obtain the composite carbon material.

[0058] The porosity, hardness and high-temperature corrosion resistance of the tantalum carbide coatings on the composite carbon materials prepared in Examples 1-2 and Comparative Example 1 were tested, and the test results are shown in Table 1.

[0059] Table 1. Porosity, hardness, and mass loss rate of tantalum carbide coatings on composite carbon materials in Examples 1-2 and Comparative Example 1.

[0060] sample Porosity / % Hardness / GPa <![CDATA[Mass loss rate (g / m 2 ·h)]]> Example 1 8 15.46 0.11 Example 2 10 15.38 0.12 Comparative Example 1 12 13.48 0.18

[0061] Porosity testing was performed using a porosity measuring instrument. Hardness testing was conducted using a nanoindentation instrument. For the high-temperature corrosion resistance test, an appropriate amount of silicon carbide powder was evenly spread on the surface of the tantalum carbide coating of the composite carbon material. The mixture was then held at 2300℃ under an argon atmosphere for 4 hours to allow all the silicon carbide powder on the tantalum carbide coating surface to sublimate. The corrosion resistance of the tantalum carbide coating was characterized by the mass loss rate of the composite carbon material before and after the heat treatment.

[0062] As shown in Table 1, the porosity and mass loss rate of the tantalum carbide coatings on the composite carbon materials of Examples 1 and 2 are lower than those of the tantalum carbide coatings on the composite carbon material of Comparative Example 1. The hardness of the tantalum carbide coatings on the composite carbon materials of Examples 1 and 2 is greater than that of the tantalum carbide coatings on the composite carbon material of Comparative Example 1. Therefore, the method provided by this invention, through the redox reaction between the reaction layer on the carbon substrate and the carbon on the surface of the carbon substrate, can obtain a more stable tantalum carbide coating on the carbon substrate. Furthermore, the composite carbon material obtained by this invention forms a tantalum metal coating on the reaction layer. This tantalum metal coating, acting as a protective layer and thermal barrier layer, can repair the tantalum carbide coating during its formation process, thereby forming a denser tantalum carbide coating on the carbon substrate.

[0063] In summary, this invention provides a composite carbon material and its preparation method. By covering the surface of a carbon matrix with a tantalum-containing slurry as a reaction layer, the reaction layer undergoes a redox reaction with the carbon on the surface of the carbon matrix to obtain a tantalum carbide coating. This effectively protects the carbon matrix, prevents corrosion by fumed silicon, and extends the service life of the carbon matrix. Furthermore, the method is convenient and has low preparation costs. Moreover, the preparation method provided by this invention, by setting a tantalum metal coating on the reaction layer, serves two purposes: firstly, the tantalum metal coating acts as a protective layer, encapsulating the reaction layer and preventing it from detaching from the carbon matrix, thus reducing the loss of the reaction layer; secondly, the tantalum metal coating also acts as a thermal barrier layer, repairing and filling pores and cracks in the tantalum carbide coating during its formation, which is beneficial for improving the density and quality of the tantalum carbide coating.

[0064] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for preparing a composite carbon material, characterized in that, At least the following steps are included: Provide a one-carbon matrix; A tantalum-containing compound is mixed with an organic solvent to obtain a tantalum-containing slurry, wherein the tantalum-containing compound includes at least one of tantalum oxide, tantalum halide and tantalum alkoxide. The tantalum-containing slurry is uniformly coated on the surface of the carbon matrix to obtain a reaction layer on the carbon matrix; Tantalum powder is uniformly coated onto the reaction layer by any one of plasma spraying, laser cladding or heating to obtain a tantalum metal coating on the reaction layer. Under vacuum, the carbon substrate with the tantalum metal coating is heated to a preset temperature and held at that temperature for a preset time, wherein the preset temperature is 2100-2400℃ and the preset time is 5-20 hours; and The heated carbon matrix was cooled to room temperature to obtain a composite carbon material.

2. The preparation method according to claim 1, characterized in that, The organic solvent includes at least one of ethanol, acetylacetone, benzene, toluene, and tetrahydrofuran.

3. The preparation method according to claim 1, characterized in that, The mass ratio of the tantalum-containing compound to the organic solvent is 1:(1-5).

4. The preparation method according to claim 1, characterized in that, The method of uniformly covering the surface of the carbon matrix with the tantalum-containing slurry includes either immersion or coating.

5. The preparation method according to claim 1, characterized in that, The tantalum powder has a particle size of 50-500 mesh, and the tantalum powder contains tantalum by mass greater than or equal to 99.50% and oxygen by mass less than or equal to 0.40%.

6. A composite carbon material obtained by the preparation method according to any one of claims 1-5, characterized in that, At least including: Carbon matrix; A tantalum carbide coating is disposed on the surface of the carbon matrix; as well as A tantalum metal coating is disposed on the tantalum carbide coating.

7. The composite carbon material according to claim 6, characterized in that, The thickness of the tantalum carbide coating is 0.1-1 mm.

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