Coating suitable for high-temperature protection of niobium-silicon alloy surface and preparation method thereof

Abstract

The invention relates to the technical field of coatings, in particular to a coating suitable for niobium-silicon alloy surface high-temperature protection and a preparation method of the coating. The coating comprises the following raw materials in parts by weight: 100-120 parts of deionized water, 60-80 parts of nickel-chromium-aluminum-yttrium alloy powder, 60-80 parts of enamel glaze, 50-60 parts of filler, 20-40 parts of a binder, 10-20 parts of nano titanium dioxide and 6-10 parts of an additive. According to the invention, during preparation of the coating, through addition of the filler, the negative thermal expansion performance of zirconium tungstate in the filler and volume shrinkage of zirconium tungstate in a high-temperature state, a buffer space is provided for thermal expansion of other materials in the coating, cracks of the coating due to thermal stress are avoided, and the high-temperature resistance of the coating is improved; kH560 enhances the interfacial compatibility of zirconium tungstate, avoids agglomeration of zirconium tungstate, and enables the zirconium tungstate to be more uniformly distributed in a coating system.

Description

Technical Field

[0001] This invention relates to the field of coating technology, specifically to a coating suitable for high-temperature protection of niobium-silicon alloy surfaces and its preparation method. Background Technology

[0002] High-temperature protective coatings for niobium-silicon alloy surfaces are used to resist damage such as oxidation and corrosion in high-temperature environments, which can improve the service life of niobium-silicon alloys under extreme working conditions. They are widely used in fields such as aero-engine turbine blades and high-temperature structural components.

[0003] In existing technologies, after a protective coating is applied to a niobium-silicon alloy and put into use, the alloy is subjected to high temperatures for extended periods. This high temperature causes the components of the coating to expand, generating compressive stress within the coating and leading to cracking and peeling, thus affecting its protective effect. Therefore, this invention provides a coating suitable for high-temperature protection of niobium-silicon alloy surfaces and its preparation method. Summary of the Invention

[0004] The purpose of this invention is to provide a coating suitable for high-temperature protection of niobium-silicon alloy surfaces and its preparation method. The coating prepared by this invention not only has good high-temperature crack prevention performance, but also excellent wear resistance, effectively improving the performance of the coating.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, the present invention provides a coating suitable for high-temperature protection of niobium-silicon alloy surfaces, comprising the following raw materials in parts by weight: 100-120 parts deionized water, 60-80 parts nickel-chromium-aluminum-yttrium alloy powder, 60-80 parts enamel glaze, 50-60 parts filler, 20-40 parts binder, 10-20 parts nano titanium dioxide, and 6-10 parts additives.

[0007] The filler is prepared by the following method:

[0008] S1: Powder preparation, using zirconium tungstate as raw material to prepare powder;

[0009] S2: Filler preparation, the powder is further processed to obtain the filler.

[0010] Further, the method for preparing the powder is as follows: zirconium tungstate is added to a mixer, an aqueous ethanol solution and KH560 are added to the mixer, the mixer is set to 600-800 r / min and stirred for 20-30 min, the resulting product is filtered to obtain a solid, the solid is sent to an oven and dried at 60-80℃ for 4-6 h to obtain the powder.

[0011] Furthermore, the mass of the ethanol-water solution is 30-40% of the mass of zirconium tungstate, the mass of KH560 is 1-3% of the mass of zirconium tungstate, and the mass concentration of the ethanol-water solution is 40-60%.

[0012] Furthermore, zirconium tungstate is selected in powder form with a particle size of 2–5 μm.

[0013] Further, the method for preparing the filler is as follows: Powdered material and cerium oxide are added to a planetary ball mill for ball milling. The speed is set to 200–300 r / min, and the processing time is 4–6 h. Argon gas is introduced during the processing. The product obtained from ball milling is added to a tube furnace. The tube furnace is set to a heating rate of 4–6 °C / min, heated to 800–1000 °C, and held at that temperature for 2–4 h. Oxygen is introduced during the heating and holding processes, with an oxygen flow rate of 80–100 cm³. 3 The process is carried out at a rate of 1000 m / min to obtain coarse material, which is then further processed to obtain filler.

[0014] Furthermore, the particle size of cerium oxide is 10–30 nm, and the mass of cerium oxide is 4–6% of the powder mass.

[0015] Further, the method for treating the coarse material is as follows: Coarse material, tetraethyl orthosilicate, anhydrous ethanol, and deionized water are added to a water bath at a temperature of 40–50°C. A magnetic stirrer is connected to the water bath and set to a speed of 400–500 r / min. The mixture is stirred at this constant temperature for 4–5 hours. After the stirring is complete, ammonia is added to adjust the pH to 9–10. The mixture is then allowed to stand at room temperature for 12–14 hours. The resulting product is then added to a centrifuge at 8000–10000 r / min for 4–6 minutes. The precipitate is collected after centrifugation and washed with ethanol. The precipitate is then placed in an oven at 60–80°C for 10–12 hours. The resulting product is then added to a muffle furnace at a heating rate of 6–8°C / min, heated to 380–420°C, and held for 40–60 minutes. Argon gas is introduced during the heating and holding process at a flow rate of 40–60 cm³. 3 The filler was prepared by reacting the coarse material, tetraethyl orthosilicate, anhydrous ethanol and deionized water at a mass ratio of 1:(0.2~0.3):(4~6):(6~10).

[0016] Furthermore, the mass ratio of each substance in the nickel-chromium-aluminum-yttrium alloy powder is 1:(2-4):(0.6-0.8):(0.4-0.6), the particle size of the nickel-chromium-aluminum-yttrium alloy powder is 2-10 μm, the particle size of the enamel glaze is 10-20 μm, and the binder is a mixture of aluminum dihydrogen phosphate and water glass, with a mass ratio of aluminum dihydrogen phosphate to water glass of 1:(0.2-0.4).

[0017] Further, the additive is prepared by the following method: zirconium oxychloride and deionized water are added to a mixer, which is set to 300-500 r / min and stirred for 20-30 min. Then, a mixture of urea and deethylene glycol is added to the mixer, which is set to 400-600 r / min and stirred for 20-30 min. The resulting product is added to a reaction vessel, which is set to 200-300 r / min and 180-200 °C and stirred at a constant temperature for 8-10 h. The resulting product is centrifuged, filtered, and dried to obtain the additive. The mass ratio of zirconium oxychloride to deionized water is 1:(2-4), the mass of urea is 20-30% of the mass of zirconium oxychloride, and the mass of deethylene glycol is 2-4% of the mass of urea.

[0018] Secondly, the present invention also provides a method for preparing a coating suitable for high-temperature protection of niobium-silicon alloy surfaces, comprising the following steps:

[0019] Step 1: Weigh out the deionized water, nickel-chromium-aluminum-yttrium alloy powder, enamel glaze, and filler as needed and add them to the mixer. Set the mixer to 400-600 r / min and stir for 10-20 minutes to obtain a slurry.

[0020] Step 2: Add binder, nano titanium dioxide and additives to the slurry, and mix the mixture at 1200-1400 r / min for 30-40 minutes to obtain the coating.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] 1. In this invention, during the preparation of the coating, the addition of fillers utilizes the negative thermal expansion properties of zirconium tungstate. Zirconium tungstate shrinks in volume at high temperatures, providing a buffer space for the thermal expansion of other materials in the coating, preventing cracks in the coating due to thermal stress, and improving the coating's high-temperature resistance. Further treatment of zirconium tungstate with KH560 enhances its interfacial compatibility, preventing agglomeration and ensuring more uniform distribution in the coating system. Cerium oxide, after ball milling, can be uniformly dispersed on the surface of zirconium tungstate, inhibiting grain growth at high temperatures and improving thermal stability. Hydrolysis of tetraethyl orthosilicate further generates a uniform silica coating, enhancing the high-temperature resistance of zirconium tungstate, increasing its negative thermal expansion retention temperature, and further improving the coating's high-temperature resistance.

[0023] 2. In this invention, during the preparation of the coating, the addition of additives can generate nano-zirconia through hydrothermal reaction. The nano-zirconia can be uniformly dispersed in the coating system, and the dispersion strengthening can improve the density of the coating and reduce the frictional mass loss of the coating. At the same time, the amino groups generated by urea hydrolysis can modify the surface of zirconia and enhance its bonding strength with the coating system materials, thereby improving the overall strength of the coating and further improving the wear resistance of the coating. Attached Figure Description

[0024] Figure 1 The invention presents a flowchart of a coating suitable for high-temperature protection of niobium-silicon alloy surfaces and its preparation method. Detailed Implementation

[0025] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] It should be noted that the raw materials used in the following embodiments are all commercially available.

[0027] Example 1:

[0028] Raw material selection: 100 parts deionized water, 60 parts nickel-chromium-aluminum-yttrium alloy powder, 60 parts enamel glaze, 50 parts filler, 20 parts binder, 10 parts nano titanium dioxide, and 6 parts additives.

[0029] The packing material is prepared by the following method:

[0030] S1: Powder preparation, using zirconium tungstate as raw material to prepare powder;

[0031] S2: Filler preparation, the powder is further processed to obtain the filler.

[0032] The method for preparing the powder is as follows: zirconium tungstate is added to a mixer, an aqueous ethanol solution and KH560 are added to the mixer, the mixer is set to 600 r / min and stirred for 20 min, the resulting product is filtered to obtain a solid, the solid is sent to an oven and dried at 60℃ for 4 h to obtain the powder.

[0033] The mass of the ethanol-water solution is 30% of the mass of zirconium tungstate, the mass of KH560 is 1% of the mass of zirconium tungstate, and the mass concentration of the ethanol-water solution is 40%.

[0034] Zirconium tungstate is selected in powder form with a particle size of 2μm.

[0035] The method for preparing the filler is as follows: Powdered material and cerium oxide are added to a planetary ball mill for ball milling. The speed is set to 200 r / min, and the processing time is 4 h. Argon gas is introduced during the processing. The ball milling product is added to a tube furnace. The tube furnace is set to a heating rate of 4 °C / min, heated to 800 °C, and held for 2 h. Oxygen is introduced during the heating and holding processes at a flow rate of 80 cm³. 3 The process is carried out at a rate of 1000 m / min to obtain coarse material, which is then further processed to obtain filler.

[0036] The cerium oxide has a particle size of 10 nm and its mass accounts for 4% of the powder mass.

[0037] The method for processing the coarse material is as follows: Coarse material, tetraethyl orthosilicate, anhydrous ethanol, and deionized water are added to a water bath at a set temperature of 40°C. A magnetic stirrer is connected to the water bath and set to a speed of 400 rpm. The mixture is stirred at this constant temperature for 4 hours. After the stirring is complete, ammonia is added to adjust the pH to 9. The mixture is then allowed to stand at room temperature for 12 hours. The resulting product is then added to a centrifuge at 8000 rpm for 4 minutes. The precipitate is collected and washed with ethanol. The precipitate is then placed in an oven at 60°C for 10 hours. The resulting product is then added to a muffle furnace at a heating rate of 6°C / min, heated to 380°C, and held for 40 minutes. Argon gas is introduced during the heating and holding process at a flow rate of 40 cm³. 3 The filler was prepared by 1:(0.2):(4):(6) in the mass ratio of coarse material, tetraethyl orthosilicate, anhydrous ethanol and deionized water.

[0038] The mass ratio of each substance in the nickel-chromium-aluminum-yttrium alloy powder is 1:(2):(0.6):(0.4), the particle size of the nickel-chromium-aluminum-yttrium alloy powder is 2μm, the particle size of the enamel glaze is 10μm, and the binder is a mixture of aluminum dihydrogen phosphate and water glass with a mass ratio of aluminum dihydrogen phosphate to water glass of 1:(0.2).

[0039] The additive is prepared by the following method: zirconium oxychloride and deionized water are added to a mixer, the mixer is set to 300 r / min and stirred for 20 min, then a mixture of urea and deethylene glycol is added to the mixer, the mixer is set to 400 r / min and stirred for 20 min, the resulting product is added to a reaction vessel, the reaction vessel is set to 200 r / min and 180 ℃, and stirred at a constant temperature for 8 h, the resulting product is centrifuged, filtered and dried to obtain the additive, wherein the mass ratio of zirconium oxychloride and deionized water is 1:(2), the mass of urea is 20% of the mass of zirconium oxychloride, and the mass of deethylene glycol is 2% of the mass of urea.

[0040] Coating preparation:

[0041] Step 1: Weigh out the deionized water, nickel-chromium-aluminum-yttrium alloy powder, enamel glaze, and filler as needed and add them to the mixer. Set the mixer to 400 r / min and stir for 10 minutes to obtain the slurry.

[0042] Step 2: Add binder, nano titanium dioxide and additives to the slurry, and mix at 1200 r / min for 30 minutes to obtain the coating.

[0043] Example 2:

[0044] Raw material selection: 110 parts deionized water, 70 parts nickel-chromium-aluminum-yttrium alloy powder, 70 parts enamel glaze, 55 parts filler, 30 parts binder, 15 parts nano titanium dioxide, and 8 parts additives.

[0045] The packing material is prepared by the following method:

[0046] S1: Powder preparation, using zirconium tungstate as raw material to prepare powder;

[0047] S2: Filler preparation, the powder is further processed to obtain the filler.

[0048] The method for preparing the powder is as follows: zirconium tungstate is added to a mixer, an aqueous ethanol solution and KH560 are added to the mixer, the mixer is set to 700 r / min and stirred for 25 min, the resulting product is filtered to obtain a solid, the solid is sent to an oven and dried at 70℃ for 5 h to obtain the powder.

[0049] The mass of the ethanol-water solution is 35% of the mass of zirconium tungstate, the mass of KH560 is 2% of the mass of zirconium tungstate, and the mass concentration of the ethanol-water solution is 50%.

[0050] Zirconium tungstate is selected in powder form with a particle size of 3μm.

[0051] The method for preparing the filler is as follows: Powdered material and cerium oxide are added to a planetary ball mill for ball milling. The speed is set to 250 r / min, and the processing time is 5 h. Argon gas is introduced during the processing. The product obtained from ball milling is added to a tube furnace. The tube furnace is set to a heating rate of 5 °C / min, heated to 900 °C, and held at that temperature for 3 h. Oxygen is introduced during the heating and holding processes at a flow rate of 90 cm³. 3 The process is carried out at a rate of 1000 m / min to obtain coarse material, which is then further processed to obtain filler.

[0052] The particle size of cerium oxide is 20 nm, and the mass of cerium oxide is 4-6% of the powder mass.

[0053] The method for processing the coarse material is as follows: Coarse material, tetraethyl orthosilicate, anhydrous ethanol, and deionized water are added to a water bath at a set temperature of 45°C. A magnetic stirrer is connected to the water bath and set to a speed of 450 rpm. The mixture is stirred at this constant temperature for 4.5 hours. After the stirring is complete, ammonia is added to adjust the pH to 9.5. The mixture is then allowed to stand at room temperature for 13 hours. The resulting product is then added to a centrifuge at 9000 rpm for 5 minutes. The precipitate is collected and washed with ethanol. The precipitate is then placed in an oven at 70°C for 11 hours. The resulting product is then added to a muffle furnace at a heating rate of 7°C / min, heated to 400°C, and held for 50 minutes. Argon gas is introduced during the heating and holding process at a flow rate of 50 cm³. 3 The filler was prepared by 1:(0.25):(5):(8) in the mass ratio of coarse material, tetraethyl orthosilicate, anhydrous ethanol and deionized water.

[0054] The mass ratio of each substance in the nickel-chromium-aluminum-yttrium alloy powder is 1:(3):(0.7):(0.5), the particle size of the nickel-chromium-aluminum-yttrium alloy powder is 6μm, the particle size of the enamel glaze is 15μm, and the binder is a mixture of aluminum dihydrogen phosphate and water glass, with a mass ratio of aluminum dihydrogen phosphate to water glass of 1:(0.3).

[0055] The additive is prepared by the following method: zirconium oxychloride and deionized water are added to a mixer, the mixer is set to 400 r / min and stirred for 25 min, then a mixture of urea and deethylene glycol is added to the mixer, the mixer is set to 500 r / min and stirred for 25 min, the resulting product is added to a reaction vessel, the reaction vessel is set to 250 r / min and 190℃, and stirred at a constant temperature for 9 h, the resulting product is centrifuged, filtered and dried to obtain the additive, wherein the mass ratio of zirconium oxychloride and deionized water is 1:(3), the mass of urea is 25% of the mass of zirconium oxychloride, and the mass of deethylene glycol is 2-4% of the mass of urea.

[0056] Coating preparation:

[0057] Step 1: Weigh out the deionized water, nickel-chromium-aluminum-yttrium alloy powder, enamel glaze, and filler as needed and add them to the mixer. Set the mixer to 500 r / min and stir for 15 minutes to obtain the slurry.

[0058] Step 2: Add binder, nano titanium dioxide and additives to the slurry, and mix at 1300 r / min for 35 minutes to obtain the coating.

[0059] Example 3:

[0060] Raw material selection: 120 parts deionized water, 80 parts nickel-chromium-aluminum-yttrium alloy powder, 80 parts enamel glaze, 60 parts filler, 40 parts binder, 20 parts nano titanium dioxide, and 10 parts additives.

[0061] The packing material is prepared by the following method:

[0062] S1: Powder preparation, using zirconium tungstate as raw material to prepare powder;

[0063] S2: Filler preparation, the powder is further processed to obtain the filler.

[0064] The method for preparing the powder is as follows: zirconium tungstate is added to a mixer, an aqueous ethanol solution and KH560 are added to the mixer, the mixer is set to 800 r / min and stirred for 30 min, the resulting product is filtered to obtain a solid, the solid is sent to an oven and dried at 80℃ for 6 h to obtain the powder.

[0065] The mass of the ethanol-water solution is 40% of the mass of zirconium tungstate, the mass of KH560 is 3% of the mass of zirconium tungstate, and the mass concentration of the ethanol-water solution is 60%.

[0066] Zirconium tungstate is selected in powder form with a particle size of 5 μm.

[0067] The method for preparing the filler is as follows: Powdered cerium oxide is added to a planetary ball mill for ball milling at a speed of 300 r / min for 6 hours. Argon gas is introduced during the process. The milled product is then added to a tube furnace, which is heated to 1000℃ at a rate of 6℃ / min and held for 4 hours. Oxygen is introduced during both the heating and holding processes at a flow rate of 100 cm³. 3 The process is carried out at a rate of 1000 m / min to obtain coarse material, which is then further processed to obtain filler.

[0068] The particle size of cerium oxide is 30 nm, and the mass of cerium oxide is 6% of the powder mass.

[0069] The method for processing the coarse material is as follows: Coarse material, tetraethyl orthosilicate, anhydrous ethanol, and deionized water are added to a water bath at a set temperature of 50°C. A magnetic stirrer is connected to the water bath and set to a speed of 500 rpm. The mixture is stirred at this constant temperature for 5 hours. After the stirring is complete, ammonia is added to adjust the pH to 10. The mixture is then allowed to stand at room temperature for 14 hours. The resulting product is then added to a centrifuge at 10,000 rpm for 6 minutes. The precipitate is collected and washed with ethanol. The precipitate is then placed in an oven at 80°C for 12 hours. The resulting product is then added to a muffle furnace at a heating rate of 8°C / min, heated to 420°C, and held for 60 minutes. Argon gas is introduced during the heating and holding process at a flow rate of 60 cm³.3 The filler was prepared by 1:(0.3):(6):(10) with the mass ratio of coarse material, tetraethyl orthosilicate, anhydrous ethanol and deionized water.

[0070] The mass ratio of each substance in the nickel-chromium-aluminum-yttrium alloy powder is 1:(4):(0.8):(0.6), the particle size of the nickel-chromium-aluminum-yttrium alloy powder is 10μm, the particle size of the enamel glaze is 20μm, and the binder is a mixture of aluminum dihydrogen phosphate and water glass with a mass ratio of aluminum dihydrogen phosphate to water glass of 1:(0.4).

[0071] The additive is prepared by the following method: zirconium oxychloride and deionized water are added to a mixer, the mixer is set to 500 r / min and stirred for 30 min, then a mixture of urea and deethylene glycol is added to the mixer, the mixer is set to 600 r / min and stirred for 30 min, the resulting product is added to a reaction vessel, the reaction vessel is set to 300 r / min and 200℃, and stirred at a constant temperature for 10 h, the resulting product is centrifuged, filtered and dried to obtain the additive, wherein the mass ratio of zirconium oxychloride and deionized water is 1:(4), the mass of urea is 30% of the mass of zirconium oxychloride, and the mass of deethylene glycol is 4% of the mass of urea.

[0072] Coating preparation:

[0073] Step 1: Weigh out the deionized water, nickel-chromium-aluminum-yttrium alloy powder, enamel glaze, and filler as needed and add them to the mixer. Set the mixer to 600 r / min and stir for 20 minutes to obtain the slurry.

[0074] Step 2: Add binder, nano titanium dioxide and additives to the slurry, and mix at 1400 r / min for 40 min to obtain the coating.

[0075] Comparative Example 1: The difference between this comparative example and Example 1 is that an equal amount of nano-silica is used to replace the additives in this comparative example.

[0076] Comparative Example 2: The difference between this comparative example and Example 1 is that an equal amount of zirconium tungstate is used to replace the filler in this comparative example.

[0077] Comparative Example 3 differs from Example 1 in that it does not contain any additives.

[0078] Comparative Example 4 differs from Example 1 in that it does not contain filler.

[0079] Performance testing: The coatings prepared in Examples 1, 2, 3, 1, 2, 3, and 4 (Comparative Examples) were subjected to performance testing. The test data are recorded in the table below:

[0080]

[0081] In the performance test, the high-temperature crack resistance test method is as follows: The coatings prepared in Example 1, Example 2, Example 3, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4 were coated and cured on the surface of niobium-silicon alloy. The coating thickness was 200 μm. The niobium-silicon alloy coated with the coating was sent into a muffle furnace. The heating rate was set to 5℃ / min, and the temperature was raised to 800℃ and held for 2 hours. After that, the niobium-silicon alloy was taken out and its surface condition (whether the coating cracked or peeled off) was observed. After the observation was completed, the niobium-silicon alloy was cooled to room temperature and sent into the muffle furnace to repeat the above heating steps. The niobium-silicon alloy was repeatedly subjected to heating, holding, taking out for observation and waiting for cooling. The number of cycles in which defects appeared on the surface coating of the niobium-silicon alloy was recorded.

[0082] The wear resistance test method is as follows: The wear resistance test of the niobium-silicon alloys coated with the coatings prepared in Examples 1, 2, 3, 1, 2, 3 and 4 is carried out using a high-temperature wear tester. The heating temperature of the high-temperature wear tester is 500℃, the abrasive hardness is 70HRC, the rotation speed is 400r / min, the contact load is 10kg, and the total wear test time is 2h. The weight of the niobium-silicon alloys before and after the wear test is recorded to obtain the weight difference before and after.

[0083] It is evident that the high-temperature crack resistance and wear resistance of the coatings prepared in Comparative Examples 1, 2, 3, and 4 are all lower than those in Examples 1, 2, and 3. This indicates that in the preparation of the coating, the addition of fillers utilizes the negative thermal expansion properties of zirconium tungstate. Zirconium tungstate shrinks in volume at high temperatures, providing a buffer space for the thermal expansion of other materials in the coating, preventing cracks caused by thermal stress, and improving the high-temperature resistance of the coating. Further treatment of zirconium tungstate, using KH560, enhances its interfacial compatibility, preventing agglomeration and ensuring more uniform distribution in the coating system. Cerium oxide, after ball milling, can be uniformly dispersed on the surface of zirconium tungstate, inhibiting grain growth at high temperatures and improving thermal stability. Hydrolysis of tetraethyl orthosilicate further generates a uniform silica coating, enhancing the high-temperature resistance of zirconium tungstate, increasing its negative thermal expansion retention temperature, and further improving the high-temperature resistance of the coating.

[0084] In the preparation of coatings, the addition of additives can generate nano-zirconia through hydrothermal reaction during the preparation process. Nano-zirconia can be uniformly dispersed in the coating system, and can improve the density of the coating through dispersion strengthening, thereby reducing the frictional mass loss of the coating. At the same time, the amino groups generated by urea hydrolysis can modify the surface of zirconia, enhance its bonding strength with the coating system materials, thereby improving the overall strength of the coating and further improving the wear resistance of the coating.

[0085] By comparing and analyzing the relevant data in the table, it can be seen that the coating prepared by this invention not only has good high-temperature crack resistance but also excellent wear resistance. This indicates that the coating provided by this invention for high-temperature protection of niobium-silicon alloy surfaces has a broader market prospect and is more suitable for widespread application.

[0086] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0087] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A coating suitable for high-temperature protection of niobium-silicon alloy surfaces, characterized in that: The raw materials include the following parts by weight: 100-120 parts deionized water, 60-80 parts nickel-chromium-aluminum-yttrium alloy powder, 60-80 parts enamel glaze, 50-60 parts filler, 20-40 parts binder, 10-20 parts nano titanium dioxide, and 6-10 parts additives. The filler is prepared by the following method: S1: Powder preparation, using zirconium tungstate as raw material to prepare powder; S2: Filler preparation, the powder is further processed to obtain the filler.

2. The coating for high-temperature protection of niobium-silicon alloy surfaces according to claim 1, characterized in that, The method for preparing the powder is as follows: zirconium tungstate is added to a mixer, an aqueous ethanol solution and KH560 are added to the mixer, the mixer is set to 600-800 r / min and stirred for 20-30 min, the resulting product is filtered to obtain a solid, the solid is sent to an oven and dried at 60-80℃ for 4-6 h to obtain the powder.

3. The coating for high-temperature protection of niobium-silicon alloy surfaces according to claim 2, characterized in that, The mass of the ethanol-water solution is 30-40% of the mass of zirconium tungstate, the mass of KH560 is 1-3% of the mass of zirconium tungstate, and the mass concentration of the ethanol-water solution is 40-60%.

4. The coating for high-temperature protection of niobium-silicon alloy surfaces according to claim 1, characterized in that, Zirconium tungstate is selected in powder form with a particle size of 2–5 μm.

5. The coating for high-temperature protection of niobium-silicon alloy surfaces according to claim 1, characterized in that, The method for preparing the filler is as follows: Powdered material and cerium oxide are added to a planetary ball mill for ball milling. The speed is set to 200–300 r / min, and the processing time is 4–6 h. Argon gas is introduced during the processing. The ball milling product is added to a tube furnace. The tube furnace is set to a heating rate of 4–6 °C / min, heated to 800–1000 °C, and held at that temperature for 2–4 h. Oxygen is introduced during the heating and holding processes, with an oxygen flow rate of 80–100 cm³. 3 The process is carried out at a rate of 1000 m / min to obtain coarse material, which is then further processed to obtain filler.

6. The coating for high-temperature protection of niobium-silicon alloy surfaces according to claim 5, characterized in that, The particle size of cerium oxide is 10-30 nm, and the mass of cerium oxide is 4-6% of the powder mass.

7. The coating for high-temperature protection of niobium-silicon alloy surfaces according to claim 1, characterized in that, The method for processing the coarse material is as follows: Coarse material, tetraethyl orthosilicate, anhydrous ethanol, and deionized water are added to a water bath at a temperature of 40–50°C. A magnetic stirrer is connected to the water bath and set to a speed of 400–500 r / min. The mixture is stirred at this constant temperature for 4–5 hours. After the stirring is complete, ammonia is added to adjust the pH to 9–10. The mixture is then allowed to stand at room temperature for 12–14 hours. The resulting product is then added to a centrifuge at 8000–10000 r / min for 4–6 minutes. The precipitate is collected and washed with ethanol. The precipitate is then placed in an oven at 60–80°C for 10–12 hours. The resulting product is then added to a muffle furnace at a heating rate of 6–8°C / min, heated to 380–420°C, and held for 40–60 minutes. Argon gas is introduced during the heating and holding process at a flow rate of 40–60 cm³. 3 The filler was prepared by reacting the coarse material, tetraethyl orthosilicate, anhydrous ethanol and deionized water at a mass ratio of 1:(0.2~0.3):(4~6):(6~10).

8. The coating for high-temperature protection of niobium-silicon alloy surfaces according to claim 1, characterized in that, The mass ratio of each substance in the nickel-chromium-aluminum-yttrium alloy powder is 1:(2-4):(0.6-0.8):(0.4-0.6), the particle size of the nickel-chromium-aluminum-yttrium alloy powder is 2-10 μm, the particle size of the enamel glaze is 10-20 μm, and the binder is a mixture of aluminum dihydrogen phosphate and water glass, with a mass ratio of aluminum dihydrogen phosphate to water glass of 1:(0.2-0.4).

9. The coating for high-temperature protection of niobium-silicon alloy surfaces according to claim 1, characterized in that, The additive is prepared by the following method: zirconium oxychloride and deionized water are added to a mixer, which is set to 300-500 r / min and stirred for 20-30 min. Then, a mixture of urea and deethylene glycol is added to the mixer, which is set to 400-600 r / min and stirred for 20-30 min. The resulting product is added to a reaction vessel, which is set to 200-300 r / min and 180-200℃ and stirred at a constant temperature for 8-10 h. The resulting product is centrifuged, filtered, and dried to obtain the additive. The mass ratio of zirconium oxychloride to deionized water is 1:(2-4), the mass of urea is 20-30% of the mass of zirconium oxychloride, and the mass of deethylene glycol is 2-4% of the mass of urea.

10. The method for preparing a coating suitable for high-temperature protection of niobium-silicon alloy surfaces according to claim 1, characterized in that, Includes the following steps: Step 1: Weigh out the deionized water, nickel-chromium-aluminum-yttrium alloy powder, enamel glaze, and filler as needed and add them to the mixer. Set the mixer to 400-600 r / min and stir for 10-20 minutes to obtain a slurry. Step 2: Add binder, nano titanium dioxide and additives to the slurry, and mix the mixture at 1200-1400 r / min for 30-40 minutes to obtain the coating.

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