Method for producing a hot zone coating, hot zone and single crystal furnace

Abstract

The application relates to a preparation method of a hot field coating, a hot field and a single crystal furnace. The preparation method comprises the following steps: dividing the hot field into carbon-carbon parts and graphite parts according to different materials; spraying the carbon-carbon parts by using a first spraying process of a spraying suspension; spraying the graphite parts by using a second spraying process of the spraying suspension, wherein the spraying suspension comprises zirconium oxide; and high-temperature calcining the sprayed hot field. According to the application, the hot field is divided into the carbon-carbon parts and the graphite parts, different spraying processes are used for the carbon-carbon parts and the graphite parts, and then the zirconium carbide can form a coating with a more stable structure on the carbon-carbon parts and the graphite parts. Meanwhile, the spraying suspension has relatively simple components, and thus has relatively low cost. Therefore, the application can solve the problems of the existing preparation method of the hot field coating, such as easy peeling of the coating, failure of the coating to achieve the desired effect or high preparation cost of the coating.

Description

Technical Field

[0001] This application relates to the field of single crystal furnace technology, and in particular to a method for preparing a thermal field coating, a thermal field, and a single crystal furnace. Background Technology

[0002] The hot zone of a single crystal furnace includes components such as heaters, flow guides, and crucibles. The outer surface of the hot zone can be coated. On the one hand, the coating can reduce power consumption. On the other hand, it can extend the service life of the hot zone and reduce production costs. However, in existing technologies, hot zone coatings often suffer from problems such as easy coating peeling, ineffective coating, or high coating costs due to improper preparation methods or excessive coating materials. Summary of the Invention

[0003] Based on this, this application provides a method for preparing a thermal field coating, a thermal field, and a single crystal furnace to improve the problems in the prior art where improper preparation methods or excessive coating materials lead to easy coating peeling, ineffective coating, or high preparation costs.

[0004] In a first aspect, this application provides a method for preparing a thermal field coating, the method comprising:

[0005] Based on the different materials, the thermal field is divided into carbon-carbon parts and graphite parts;

[0006] The carbon-carbon component is coated using a first spraying process with a spraying suspension; the graphite component is coated using a second spraying process with the same spraying suspension, wherein the spraying suspension comprises zirconium oxide and a chemical reagent, wherein the chemical reagent is one or more of ethanol, acetonitrile, diethyl ether, and dimethyl ether.

[0007] The sprayed hot zone is then subjected to high-temperature calcination.

[0008] In one embodiment, the carbon-carbon part is coated using a spray suspension in a first spraying process, including:

[0009] The carbon-carbon part is sprayed with the aforementioned spray suspension 5-6 times, and dried after each spraying. The total amount of the spray suspension is 0.32-0.36 g / cm³. 2 .

[0010] In one embodiment, the graphite part is coated using the spray suspension via a second spraying process, including:

[0011] The graphite part is sprayed with the aforementioned spray suspension 3-4 times, and dried after each spraying. The total spraying amount of the spray suspension is 0.27-0.31 g / cm³. 2 .

[0012] In one embodiment, the amount of the sprayed suspension is reduced with each spraying, and the drying time of the sprayed suspension is increased with each spraying.

[0013] In one embodiment, the carbon-carbon part is sprayed 5-6 times using the spray suspension, and dried after each spraying, including:

[0014] The carbon-carbon part is sprayed five times. During the first spray, the amount of the sprayed suspended matter is 0.12-0.135 g / cm³. 2 The drying time is 15-20 minutes; during the second spraying, the amount of the sprayed suspension is 0.08-0.09 g / cm³. 2 The drying time is 20-25 minutes; during the third spraying, the amount of the sprayed suspension is 0.06-0.068 g / cm³. 2 The drying time is 25-30 minutes; during the fourth spraying, the amount of the sprayed suspension is 0.04-0.045 g / cm³. 2 The drying time is 30-35 minutes; during the fifth spraying, the amount of the sprayed suspension is 0.02-0.022 g / cm³. 2 The drying time is 35-40 minutes.

[0015] In one embodiment, the graphite part is sprayed 3-4 times using the spray suspension, and dried after each spraying, including:

[0016] The graphite part was sprayed three times. During the first spraying, the amount of the sprayed suspension was 0.135-0.155 g / cm³. 2 The drying time is 20-25 minutes; during the second spraying, the amount of the sprayed suspension is 0.108-0.124 g / cm³. 2 The drying time is 50-55 minutes; during the third spraying, the amount of the sprayed suspension is 0.027-0.031 g / cm³. 2 The drying time is 80-85 minutes.

[0017] In one embodiment, the hot zone after spraying is subjected to high-temperature calcination, including:

[0018] The sprayed thermal field is placed inside the furnace;

[0019] Argon or nitrogen gas is introduced into the furnace body, and the flow rate of argon or nitrogen gas is controlled at 80-100 L / min; the pressure inside the furnace body is controlled at 1000-1200 Pa; the temperature inside the furnace body is controlled at above 1900℃, and the furnace body is kept at a constant temperature for more than 15 minutes.

[0020] In one embodiment, before spraying the carbon-carbon part with a first spraying process using a spraying suspension, and before spraying the graphite part with the second spraying process using the spraying suspension, the preparation method further includes:

[0021] Zirconia powder and chemical reagents were uniformly mixed to prepare a spray suspension. The mixing ratio of zirconia powder to chemical reagents was 1:30.

[0022] Secondly, this application provides a thermal field on which a coating is disposed, the coating being prepared using any of the thermal field coating preparation methods provided in this application.

[0023] Thirdly, this application provides a single crystal furnace, which includes any of the thermal fields provided in this application.

[0024] This application categorizes the thermal field into porous carbon-carbon components and hydrostatically dense graphite components based on their materials. Different spraying processes are applied to these two types of components, ensuring good adhesion of the sprayed suspension to each. When the sprayed thermal field is further calcined at high temperatures, the effectively adhered spray suspension allows for a full reaction between zirconium oxide and carbon. This results in zirconium carbide directly adhering to the graphite component or filling the voids in the carbon fibers of the carbon-carbon component, leading to a tighter bond between the zirconium carbide and the thermal field. This tighter bond allows for a more structurally stable coating on both carbon-carbon and graphite components, preventing coating detachment and ensuring proper function. Furthermore, since the primary active component of the spray suspension is zirconium oxide, its relatively simple composition results in a lower cost. This application can improve the problems in the prior art where improper preparation methods of thermal field coatings or excessive coating materials cause the coating to easily peel off, fail to achieve the desired effect, or have high preparation costs. Attached Figure Description

[0025] Figure 1 This is a flowchart of the method for preparing the thermal field coating provided in Embodiment 1 of this application. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0027] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention.

[0028] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0029] The orientations or positional relationships indicated by terms such as "upper," "lower," "left," "right," "middle," "longitudinal," "lateral," "horizontal," "inner," "outer," "radial," and "circumferential" used in this specification are based on the orientations or positional relationships shown in the accompanying drawings and are only for the purpose of simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0030] Example 1

[0031] Embodiment 1 of this application provides a method for preparing a thermal field coating, such as... Figure 1 As shown, the preparation method includes the following steps:

[0032] S1. Based on the different materials, the thermal field is divided into carbon-carbon parts and graphite parts;

[0033] S2. A carbon-carbon part is coated using a first spraying process with a spraying suspension; a graphite part is coated using a second spraying process with a spraying suspension, wherein the spraying suspension includes zirconium oxide and a chemical reagent, and the chemical reagent is one or more of ethanol, acetonitrile, diethyl ether, and dimethyl ether.

[0034] S3. The hot zone after spraying is subjected to high-temperature calcination.

[0035] like Figure 1As shown, in step S1, it is exemplarily illustrated that the thermal field constituting the carbon-carbon component is made of a carbon / carbon composite material, such as a crucible, which can be made of a carbon / carbon composite material, i.e., a carbon-carbon crucible. The thermal field constituting the graphite component is made of graphite material, such as a heater or cover plate, which can be made of graphite, i.e., a graphite heater, a graphite cover plate, etc. are formed sequentially. Here, carbon / carbon composite material is short for carbon fiber reinforced carbon-based composite material, specifically including carbon fibers. Due to the presence of carbon fibers, the carbon-carbon component has a loose and porous structure. In contrast, the graphite component has an isostatically compressed and dense structure. This embodiment uses different spraying processes to spray the thermal field based on the different materials used.

[0036] like Figure 1 As shown, in step S2, it is exemplarily illustrated that when the material of the hot zone is a carbon-carbon component, a first spraying process can be used for spraying, which can be defined as step S2′. When the material of the hot zone is a graphite component, a second spraying process can be used for spraying, which can be defined as step S2″. It is easy to understand that steps S2′ and S2″ are parallel steps. For different components, one of steps S2′ and S2″ should be selected for execution. The difference between the first and second spraying processes may specifically include the number of sprays, the amount of material sprayed each time, and the drying time after each spray. Furthermore, this embodiment uses a spray suspension to spray the hot zone.

[0037] like Figure 1 As shown, in step S3, it is exemplarily illustrated that the sprayed hot zone needs to undergo further high-temperature calcination. During high-temperature calcination, the sprayed suspension on the outer surface of the hot zone can react with the hot zone to form a coating. Specifically, the zirconium oxide in the sprayed suspension can react with carbon under high-temperature conditions to generate zirconium carbide and carbon dioxide. For graphite parts, the produced zirconium carbide can be directly attached to the graphite parts to form a coating. For carbon-carbon parts, the generated zirconium carbide can also be coated on the carbon fibers of the carbon-carbon parts in the form of zirconium carbide aerogel, while filling the pores of the carbon fibers to form a coating on the carbon-carbon parts.

[0038] Understandably, this application categorizes the thermal field into porous carbon-carbon components and hydrostatically dense graphite components based on their materials, employing different spraying processes for each to ensure good adhesion of the sprayed suspension to both. When the sprayed thermal field undergoes further calcination at high temperatures, the effectively adhered sprayed suspension allows for a full reaction between zirconium oxide and carbon. This results in zirconium carbide directly adhering to the graphite component or filling the voids in the carbon fibers of the carbon-carbon component, leading to a tighter bond between the zirconium carbide and the thermal field. This tighter bond allows for a more structurally stable coating on both carbon-carbon and graphite components, preventing coating detachment and ensuring proper function. Furthermore, since the primary active component of the sprayed suspension is zirconium oxide, its relatively simple composition results in a relatively low cost. Based on the foregoing, this application can improve the problems in the prior art where improper preparation methods of thermal field coatings or excessive coating materials lead to easy coating peeling, ineffective coatings, or high coating preparation costs.

[0039] Specifically, the carbon-carbon part is sprayed using a spray suspension in a first spraying process (i.e., step S2′), which includes the following steps:

[0040] S21'. Apply the aforementioned spray suspension to the carbon-carbon part 5-6 times, drying after each application. The total amount of the spray suspension is 0.32-0.36 g / cm³. 2 .

[0041] like Figure 1 As shown in this embodiment, it is exemplarily illustrated that the total amount of sprayed suspended matter should be appropriate. If the total amount of sprayed suspended matter is insufficient, the resulting coating thickness will be too thin, making it difficult for the coating to perform its intended function. If the total amount of sprayed suspended matter is excessive, the resulting coating thickness will be too thick, making the coating prone to peeling off. During spraying, the thickness of a single spray should not be too thick; at the same time, sufficient drying should be carried out after each spray, otherwise defects such as cracking, wrinkling, and sagging of the sprayed suspended matter in the thermal field are likely to occur.

[0042] In this embodiment, because the carbon-carbon component has a loose and porous structure, the number of spraying passes and the total amount of sprayed suspended particles should be relatively high. This ensures a good spraying effect of the suspended particles on the carbon-carbon component, allowing them to form a stable and effective adhesion, thereby guaranteeing the stability and effectiveness of the coating on the carbon-carbon component. The total amount of sprayed suspended particles can be 0.32-0.36 g / cm³. 2For example, it can be 0.32, 0.33, 0.34, 0.35, and 0.36 g / cm³. 2 Furthermore, by allowing the coating to dry after each application, the coating effect of the sprayed suspension can be further improved.

[0043] It is understood that by using a reasonable first spraying process to spray carbon carbon parts, this embodiment can ensure the stability and effectiveness of the coating on the carbon carbon parts.

[0044] More specifically, the graphite part is sprayed using a spray suspension in a second spraying process (i.e., step S2″), including:

[0045] S21″ Apply a spray suspension to the graphite part 3-4 times, drying after each application. The total spray suspension amount is 0.27-0.31 g / cm³. 2 .

[0046] like Figure 1 As shown in this embodiment, it is exemplarily illustrated that, since the graphite part has a hydrostatically dense structure, the number of coating passes for the carbon-carbon part should be relatively small, and the total amount of sprayed suspended matter should also be relatively small. This ensures the effective coating of the sprayed suspended matter on the graphite part, allowing it to form a stable and effective adhesion, thereby guaranteeing the stability and effectiveness of the coating on the graphite part. The total amount of sprayed suspended matter can be 0.27-0.31 g / cm³. 2 For example, it can be 0.27, 0.28, 0.29, 0.30, and 0.31 g / cm³. 2 Similarly, by allowing drying after each spray, the spraying effect of the suspended particles can be further improved.

[0047] It is understood that by using a reasonable second spraying process to spray the graphite parts in this embodiment, the stability and effectiveness of the coating on the graphite parts can be guaranteed.

[0048] More specifically, the amount of sprayed suspended matter decreases with each spraying, while the drying time of the sprayed suspended matter increases with each spraying.

[0049] In this embodiment, it is exemplarily illustrated that during multiple spraying operations, the amount of paint applied in each spraying can be gradually reduced as the number of spraying operations increases. This allows for more accurate control of the paint thickness, thereby avoiding situations where the total amount of paint applied is insufficient or excessive. Simultaneously, the drying time after each spraying can be gradually increased to prevent insufficient drying time from negating the wetting effect of subsequent spraying on previous spraying.

[0050] It is understood that this embodiment can further ensure the spraying effect of the first and second spraying processes by gradually reducing the amount of coating in each spraying process and gradually increasing the drying time after each spraying.

[0051] More specifically, the carbon-carbon parts are sprayed with a spray suspension 5-6 times, and dried after each spraying (i.e., step S21′), including the following steps:

[0052] The carbon-carbon parts were sprayed five times. During the first spray, the amount of suspended particles sprayed was 0.12-0.135 g / cm³. 2 The drying time is 15-20 minutes; for the second spray, the amount of suspended matter sprayed is 0.08-0.09 g / cm³. 2 The drying time is 20-25 minutes; for the third spray, the amount of suspended matter sprayed is 0.06-0.068 g / cm³. 2 The drying time is 25-30 minutes; for the fourth spray, the amount of suspended matter sprayed is 0.04-0.045 g / cm³. 2 The drying time is 30-35 minutes; for the fifth spray, the amount of suspended matter sprayed is 0.02-0.022 g / cm³. 2 The drying time is 35-40 minutes.

[0053] In this embodiment, it is exemplarily illustrated that the sprayed suspension can be sprayed onto the carbon carbon part 5 times. During the first spray, the amount of sprayed suspension can be 0.12-0.135 g / cm³. 2 For example, it can be 0.12, 0.125, 0.13, and 0.135 g / cm³. 2 The drying time can be 15-20 minutes, for example, 15, 16, 17, 18, 19 and 20 minutes.

[0054] For the second coat, the amount of suspended particles sprayed can be 0.08-0.09 g / cm³. 2 For example, it can be 0.08, 0.085, and 0.09 g / cm³. 2 The drying time can be 20-25 minutes, for example, 20, 21, 22, 23, 24 and 25 minutes.

[0055] For the third coat, the amount of suspended particles sprayed can be 0.06-0.068 g / cm³. 2 For example, it can be 0.06, 0.062, 0.064, 0.066, and 0.068 g / cm³. 2The drying time can be 25-30 minutes, for example, 25, 26, 27, 28, 29 and 30 minutes.

[0056] For the fourth coat, the amount of suspended particles sprayed can be 0.04-0.045 g / cm³. 2 For example, it can be 0.04, 0.041, 0.042, 0.043, 0.044, and 0.045 g / cm³. 2 The drying time is 30-35 minutes, for example, 30, 31, 32, 33, 34 and 35 minutes.

[0057] During the fifth spraying, the spraying amount of suspended particles was 0.02-0.022 g / cm³. 2 For example, it can be 0.02, 0.021, and 0.022 g / cm³. 2 The drying time is 35-40 minutes, for example, 35, 36, 37, 38, 39 and 40 minutes.

[0058] Of course, in some embodiments, the carbon carbon parts can be sprayed 6 times, and the amount of sprayed each time and the drying time after each spraying can be reasonably set according to actual needs.

[0059] It is understood that by reasonably setting the number of spraying times, the amount of paint applied each time, and the drying time after each spraying, this embodiment can further ensure the coating effect of the carbon carbon parts through the first spraying process.

[0060] More specifically, the graphite parts are sprayed with a spray suspension 3-4 times, and dried after each spraying (i.e., step S21″), including the following steps:

[0061] The graphite parts were sprayed three times. During the first spray, the amount of suspended matter sprayed was 0.135-0.155 g / cm³. 2 The drying time is 20-25 minutes; during the second spraying, the amount of suspended matter sprayed is 0.108-0.124 g / cm³. 2 The drying time is 50-55 minutes; for the third spray, the amount of suspended matter sprayed is 0.027-0.031 g / cm³. 2 The drying time is 80-85 minutes.

[0062] In this embodiment, it is exemplarily illustrated that the sprayed suspension can be sprayed onto the graphite part three times. During the first spray, the amount of sprayed suspension can be 0.135-0.155 g / cm³. 2 For example, it can be 0.135, 0.14, 0.145, 0.15, and 0.155 g / cm³. 2The drying time can be 20-25 minutes, for example, 20, 21, 22, 23, 24 and 25 minutes.

[0063] For the second coat, the amount of suspended particles sprayed can be 0.108-0.124 g / cm³. 2 For example, it can be 0.108, 0.112, 0.116, 0.12, and 0.124 g / cm³. 2 The drying time can be 50-55 minutes, for example, 50, 51, 52, 53, 54 and 55 minutes.

[0064] For the third coat, the amount of suspended particles sprayed can be 0.027-0.031 g / cm³. 2 For example, it can be 0.027, 0.028, 0.029, 0.03, and 0.031 g / cm³. 2 The drying time can be 80-85 minutes, for example, 80, 81, 82, 83, 84 and 85 minutes.

[0065] Of course, in some embodiments, the graphite part can be sprayed four times, and the amount of sprayed each time and the drying time after each spraying can be reasonably set according to actual needs.

[0066] It is understood that by reasonably setting the number of sprayings on the graphite parts, the amount of spraying each time, and the drying time after each spraying, this embodiment can further ensure the spraying effect of the graphite parts through the second spraying process.

[0067] Specifically, the hot zone after spraying is subjected to high-temperature calcination (i.e., step S3), which includes the following steps:

[0068] S31. Place the hot zone after spraying inside the furnace;

[0069] S32. Introduce argon or nitrogen into the furnace, controlling the flow rate of argon or nitrogen to 80-100 L / min; control the pressure inside the furnace to 1000-1200 Pa; control the temperature inside the furnace to above 1900℃, and maintain the furnace temperature constant for at least 15 minutes.

[0070] In this embodiment, the furnace body can be a single-crystal furnace or other high-temperature furnaces, with the former being used as an example. The hot zone can be suspended inside the furnace body for thorough calcination. After the sprayed hot zone is placed in the furnace body, argon or nitrogen gas can be introduced into the furnace body, and the flow rate of argon or nitrogen gas can be controlled at 80-100 L / min to create an inert environment for calcination, thereby reducing impurities in the coating. For example, the flow rate of argon or nitrogen gas can be 80, 90, and 100 L / min. The pressure inside the furnace body can also be controlled at 1000-1200 Pa to ensure sufficient pressure for the calcination environment. For example, the pressure can be 1000, 1100, and 1200 Pa. At the same time, the temperature inside the furnace body can be controlled above 1900℃ to ensure sufficient temperature for the calcination environment. For example, the temperature can be 2000, 2100, and 2200℃. Furthermore, the furnace body temperature can be controlled to remain constant for more than 15 minutes to ensure sufficient calcination of the hot zone, such as controlling the furnace body temperature to remain constant for 16, 17, 18 and 19 minutes.

[0071] It is understood that by placing the heat field inside the furnace and reasonably controlling the furnace, this embodiment can ensure the calcination effect of the heat field, so that the zirconium oxide in the sprayed suspension can fully react with carbon and is less likely to produce impurities, thereby ensuring the stability and effectiveness of the generated coating.

[0072] Specifically, before spraying the carbon-carbon part with the first spraying process using the spraying suspension, and before spraying the graphite part with the second spraying process using the spraying suspension (i.e., step S2), the preparation method further includes:

[0073] Zirconia powder and chemical reagents were uniformly mixed to prepare a spray suspension. The mixing ratio of zirconia powder to chemical reagents was 1:30.

[0074] In this embodiment, it is exemplarily illustrated that a sprayable suspension can be prepared by thoroughly mixing zirconium oxide powder with a chemical reagent. Before each spraying, the zirconium oxide powder and chemical reagent can be mixed again to ensure the uniformity of the zirconium oxide powder during each spraying. The step of preparing the sprayable suspension occurs before step S2, and this step can occur after step S1, i.e., between steps S1 and S2; it can also occur before step S1; or it can be performed simultaneously with step S1.

[0075] It is understood that this embodiment uses a reasonable formulation of sprayed suspension to facilitate the adhesion of zirconium oxide to the thermal field, thereby enabling zirconium oxide to react fully with carbon.

[0076] This application categorizes the thermal field into porous carbon-carbon components and hydrostatically dense graphite components based on their materials. Different spraying processes are applied to these two types of components, ensuring good adhesion of the sprayed suspension to each. When the sprayed thermal field is further calcined at high temperatures, the effectively adhered spray suspension allows for a full reaction between zirconium oxide and carbon. This results in zirconium carbide directly adhering to the graphite component or filling the voids in the carbon fibers of the carbon-carbon component, leading to a tighter bond between the zirconium carbide and the thermal field. This tighter bond allows for a more structurally stable coating on both carbon-carbon and graphite components, preventing coating detachment and ensuring proper function. Furthermore, since the primary active component of the spray suspension is zirconium oxide, its relatively simple composition results in a lower cost. This application can improve the problems in the prior art where improper preparation methods of thermal field coatings or excessive coating materials cause the coating to easily peel off, fail to achieve the desired effect, or have high preparation costs.

[0077] Example 2

[0078] Embodiment 2 of this application provides a thermal field with a coating, which is prepared using any of the thermal field coating preparation methods provided in this application.

[0079] Example 3

[0080] Embodiment 3 of this application provides a single crystal furnace, which includes any of the thermal fields provided in this application.

[0081] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0082] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for preparing a thermal field coating, characterized in that, The preparation method includes: Based on the different materials, the thermal field is divided into carbon-carbon parts and graphite parts; The carbon-carbon parts are sprayed using a first spraying process with a spray suspension, and dried after each spraying. When using the first spraying process, the total amount of the spray suspension is 0.32-0.36 g / cm³. 2 The graphite part is sprayed using the aforementioned spray suspension through a second spraying process, and drying is performed after each spraying. When using the second spraying process, the total spraying amount of the spray suspension is 0.27-0.31 g / cm³. 2 When spraying using the first spraying process and the second spraying process, the amount of the sprayed suspension decreases with each spraying, and the drying time of the sprayed suspension increases with each spraying. The sprayed suspension includes zirconium oxide and chemical reagents, and the chemical reagents are one or more of ethanol, acetonitrile, diethyl ether, and dimethyl ether. The sprayed hot zone is then subjected to high-temperature calcination.

2. The method for preparing the thermal field coating according to claim 1, characterized in that, The carbon-carbon part is coated using a first spraying process with a spray suspension, including: The carbon part is sprayed 5-6 times using the spray suspension.

3. The method for preparing the thermal field coating according to claim 2, characterized in that, Spraying the graphite part with the aforementioned spray suspension using a second spraying process includes: The graphite part is sprayed 3-4 times using the spray suspension.

4. The method for preparing the thermal field coating according to claim 3, characterized in that, The carbon-carbon part is sprayed 5-6 times with the aforementioned spray suspension, and dried after each spraying, including: The carbon-carbon part is sprayed five times. During the first spray, the amount of the sprayed suspended matter is 0.12-0.135 g / cm³. 2 The drying time is 15-20 minutes; during the second spraying, the amount of the sprayed suspension is 0.08-0.09 g / cm³. 2 The drying time is 20-25 minutes; for the third spray, the amount of the sprayed suspension is 0.06-0.068 g / cm², and the drying time is 25-30 minutes; for the fourth spray, the amount of the sprayed suspension is 0.04-0.045 g / cm². 2 The drying time is 30-35 minutes; during the fifth spraying, the amount of the sprayed suspension is 0.02-0.022 g / cm³. 2 The drying time is 35-40 minutes.

5. The method for preparing the thermal field coating according to claim 4, characterized in that, The graphite part is sprayed with the aforementioned spray suspension 3-4 times, and dried after each spraying, including: The graphite part was sprayed three times. During the first spraying, the amount of the sprayed suspension was 0.135-0.155 g / cm³. 2 The drying time is 20-25 minutes; during the second spraying, the amount of the sprayed suspension is 0.108-0.124 g / cm³. 2 The drying time is 50-55 minutes; during the third spraying, the amount of the sprayed suspension is 0.027-0.031 g / cm³. 2 The drying time is 80-85 minutes.

6. The method for preparing the thermal field coating according to claim 1, characterized in that, The hot zone after spraying is subjected to high-temperature calcination, including: The sprayed thermal field is placed inside the furnace; Argon or nitrogen gas is introduced into the furnace body, and the flow rate of argon or nitrogen gas is controlled at 80-100 L / min; the pressure inside the furnace body is controlled at 1000-1200 Pa; the temperature inside the furnace body is controlled at above 1900℃, and the furnace body is kept at a constant temperature for more than 15 minutes.

7. The method for preparing the thermal field coating according to claim 1, characterized in that, The carbon-carbon part is sprayed using a first spraying process with a spraying suspension. Before spraying the graphite part with the spray suspension using the second spraying process, the preparation method further includes: Zirconia powder and chemical reagents were uniformly mixed to prepare a spray suspension. The mixing ratio of zirconia powder to chemical reagents was 1:

30.

8. A thermal field, characterized in that, A coating is provided on the thermal field, and the coating is prepared by the method for preparing thermal field coatings as described in any one of claims 1-7.

9. A single crystal furnace, characterized in that, The single crystal furnace includes the thermal field as described in claim 8.

Images