A method for manufacturing a ceramic matrix composite with an abradable coating and applications thereof

Abstract

The present application relates to the technical field of coating material, in particular to a preparation method and application of ceramic matrix composite material with abradable coating, which is composed of the following raw materials by weight: a ceramic matrix composite material with abradable coating, which is composed of the following raw materials by weight: base ceramic blank 80-90 parts, first functional material 6-8 parts, second functional material 4-7 parts, calcium fluoride 0.5-1 part, polyvinyl alcohol 0.3-0.5 part, and anhydrous ethanol 30-35 parts. The present application changes the brittle and hard characteristics of traditional ceramic like glass into flexible characteristics, fundamentally solves the problem of thermal shock failure of ceramic coating, simultaneously solves the shortcoming that the lubricating additive in traditional ceramic coating can only be passively protected, and greatly improves the comprehensive performance of ceramic products.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coating materials, in particular to a preparation method and application of a ceramic matrix composite material with an abradable coating. BACKGROUND

[0002] High-temperature industrial valves are the core sealing components of modern energy equipment, and their working environment often faces high-temperature steam erosion and pressure impact. To meet the requirements of severe working conditions, ceramic matrix coatings are widely used for valve seat sealing surface reinforcement. These materials use alumina, zirconia and other ceramics as the matrix, and form a wear-resistant protective layer on the surface of the metal substrate through thermal spraying or sintering process.

[0003] In the application of traditional ceramic coatings in high-temperature and high-pressure valves, the inherent brittle and hard characteristics of ceramics, their high thermal expansion coefficient and low thermal conductivity result in a sharp accumulation of temperature gradient, and the internal expansion difference cannot be buffered, resulting in local high stress concentration, which can cause the initiation and propagation of micro cracks, making the ceramic valve poor in thermal cycle impact resistance. Based on this, the present application provides a preparation method and application of a ceramic matrix composite material with an abradable coating. SUMMARY

[0004] The purpose of the present application is to provide a preparation method and application of a ceramic matrix composite material with an abradable coating to solve the problems raised in the background art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solution: a ceramic matrix composite material with an abradable coating, which is composed of the following raw materials by weight: 80-90 parts of base ceramic blank, 6-8 parts of first functional material, 4-7 parts of second functional material, 0.5-1 parts of calcium fluoride, 0.3-0.5 parts of polyvinyl alcohol, and 30-35 parts of anhydrous ethanol.

[0006] The preparation method of the first functional material is as follows: mix glucose and deionized water in a mass ratio of 1: (5-6), and hydrothermally react at 180-220℃ for 10-12h, with nitrogen gas protection during the process, to obtain carbon microspheres. Disperse the carbon microspheres in ethanol, and then add zirconium oxychloride and boric acid, and stir at 55-65℃ and 80-110rpm for 6-8h. Dry the obtained product to obtain a powder material, and then calcine the powder material in a tube furnace to obtain the first functional material.

[0007] Preferably, the tube furnace is set to have a heating rate of 8-10℃ / min, and the temperature is raised to 1450-1550℃, with an argon gas flow of 200mL / min during the process.

[0008] Preferably, the mass ratio of the carbon microspheres, ethanol, zirconium oxychloride and boric acid is 5: (9-11): (3-4): (1-2).

[0009] Preferably, the preparation method of the second functional material is:

[0010] Step 1: mix sodium hydroxide and sodium carbonate in a mass ratio of 5:3, and then dissolve them in deionized water to obtain an alkaline solution;

[0011] Step 2: select magnesium nitrate, aluminum nitrate, and copper nitrate in a mass ratio of 5:3:1, and then put them into a blender to be treated at a stirring speed of 100-200 rpm for 30-60 min to obtain a mixture;

[0012] Step 3: add the mixture obtained in Step 2 and the alkaline solution obtained in Step 1 into a reaction kettle, and treat them at a stirring speed of 300-400 rpm and a temperature of 75-85℃ for 3-5 h, and then take the precipitate after centrifugal filtration to obtain a filter cake;

[0013] Step 4: add the filter cake into ethanol, and then add tetraethyl orthosilicate, heat to 45-50℃, and treat at a stirring speed of 200-300 rpm for 3-4 h, dry the obtained product at a temperature of 100℃ for 1-2 h, and then put it into a muffle furnace, set the heating rate to 5℃ / min, heat to 580-620℃, and calcine for 4-5 h to obtain the second functional material.

[0014] Preferably, the mass of deionized water in Step 1 is 1-2 times the total mass of sodium hydroxide and sodium carbonate, the mass ratio of the mixture and the alkaline solution is 1:(2-3), and the mass ratio of the filter cake and ethanol in Step 4 is 1:(3-5).

[0015] Preferably, the mass of tetraethyl orthosilicate in Step 4 is 8-10% of the mass of the filter cake.

[0016] Preferably, the raw materials of the base ceramic blank consist of alumina, silicon dioxide, and yttrium oxide, and the mass ratio of each raw material is (1.8-2.2):(0.9-1.1):(0.12-0.14).

[0017] Preferably, the particle size of the alumina is 4-6 μm, the particle size of the silicon dioxide is 3-5 μm, and the particle size of the yttrium oxide is 1-2 μm.

[0018] Preferably, a preparation method of a ceramic matrix composite material with an abradable coating comprises the following steps:

[0019] S1: mix the base ceramic blank and calcium fluoride at a stirring speed of 50-100 rpm for 5-10 min to obtain a dry mixture;

[0020] S1: add the first functional material, the second functional material, polyvinyl alcohol, anhydrous ethanol, and the dry mixture obtained in S1 into a ball mill for grinding treatment to obtain a wet mixture;

[0021] S3: The wet grinding material is dried in vacuum at 60-70 DEG C for 12-14 hours, and the obtained product is sieved through a 100 mesh sieve to obtain a mixed powder;

[0022] S4: The mixed powder is loaded into a rubber mold and cold isostatic pressing is performed at 200 MPa for 5 minutes to obtain a green body;

[0023] S5: The green body is heated to 300 DEG C at a heating rate of 2 DEG C per minute in an atmosphere furnace for 2 hours, and then is transferred into a graphite mold and heated to 1500 DEG C at a heating rate of 5 DEG C per minute under argon protection for 4 hours to obtain a ceramic matrix composite material with an abradable coating.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] 1. In the first functional material of the present application, the through-hole network precisely controlled by the carbon microsphere template constructs a three-dimensional elastic stress buffer system in the ceramic matrix. When the ceramic valve sealing surface bears high pressure impact, the directional bending of the hole wall in the buffer system converts the point-like concentrated stress into distributed deformation, effectively absorbs the stress wave energy, and in the thermal shock working condition, the micro air gap layer formed between the hole walls in the instant cooling blocks the heat conduction path, so that the expansion difference caused by the temperature gradient is gradually resolved by thousands of micro-hole units, and the curled whiskers formed by the anisotropic growth of the calcined zirconium boride crystals along the hole channel produce a bridging effect, which, under the mutual coordination, changes the brittle and hard characteristics of the traditional ceramic like glass into flexible characteristics, and fundamentally solves the problem of thermal shock failure of the ceramic coating.

[0026] 2. In the preparation process of the second functional material of the present application, the directional assembly of the magnesium-aluminum-copper ternary precursor in the alkaline solution forms a hydrotalcite-like matrix with a nano-layered structure, in which the copper ions are precisely anchored between the crystal lattice layers, the hydrolysis and condensation of tetraethyl orthosilicate in the ethanol environment generates a silica coating layer, and the thermal expansion and contraction memory effect is generated during the heat treatment process, so that the sealing is kept intact at room temperature to avoid the loss of active components, when the friction temperature breaks through the critical point, the micron-level grid cracks are generated on the layer to release the molten copper compound to form a self-healing film, at the same time, the magnesium component constitutes the main crystal lattice network to give the structural strength, the aluminum component optimizes the thermal stability of the material to prevent high temperature inactivation, the interface reaction between the aluminum element and the silicon shell generates mullite buffer phase, which not only maintains the integrity of the coating layer but also controls the copper release rate, so as to achieve the dynamic balance of wear and repair, form a negative feedback mechanism of more wear and more protection, so that the material has the abradable property, and solves the shortcoming that the lubricating additive in the traditional ceramic coating can only be passively protected.

[0027] 3. In this invention, when the first functional material acting as the honeycomb skeleton and the second functional material forming the core-shell particles work together on the matrix, the boron-oxygen active sites on the inner wall of the zirconium boride pores and the magnesium oxide surface of the core-shell particles form a stable magnesium borate bonding interface, thereby exhibiting a memory effect during thermal shock cycling. Under friction conditions, the lubricating phase overflowing from the pores is filtered twice by the honeycomb structure, and after removing impurities, an ultra-pure repair film is formed. The two achieve material energy exchange through chemical bonds. This biomimetic synergy gives the coating material reconstruction characteristics, greatly improving the comprehensive performance of ceramic products. Detailed Implementation

[0028] 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.

[0029] Example 1: A ceramic matrix composite material with a wearable coating, composed of the following raw materials in parts by weight: 80 parts of basic ceramic blank, 6 parts of first functional material, 4 parts of second functional material, 0.5 parts of calcium fluoride, 0.3 parts of polyvinyl alcohol, and 30 parts of anhydrous ethanol.

[0030] The preparation method of the first functional material is as follows: glucose and deionized water are mixed at a mass ratio of 1:5 and hydrothermally reacted at 180°C for 10 hours. Nitrogen gas is introduced for protection during the process to obtain carbon microspheres. The carbon microspheres are dispersed in ethanol, and zirconium oxychloride and boric acid are added. The mixture is stirred at 55°C and 80 rpm for 6 hours. The resulting product is dried to obtain powder material. The powder material is placed in a tube furnace for calcination to obtain the first functional material.

[0031] The tubular atmosphere furnace is set to a heating rate of 8℃ / min, heating to 1450℃, and holding for 2 hours. Argon gas is introduced during the process at a flow rate of 200mL / min.

[0032] The mass ratio of carbon microspheres, ethanol, zirconium oxychloride, and boric acid is 5:9:3:1.

[0033] The preparation method of the second functional material is as follows:

[0034] Step 1: Mix sodium hydroxide and sodium carbonate in a mass ratio of 5:3 and dissolve in deionized water to obtain an alkaline solution;

[0035] Step 2: Select magnesium nitrate, aluminum nitrate and copper nitrate in a mass ratio of 5:3:1, put them into a mixer, and process them at a stirring speed of 100 rpm for 30 minutes to obtain a mixture;

[0036] Step 3: The mixture prepared in step 2 and the alkaline solution prepared in step 1 are added to a reaction kettle, treated at 300 rpm, 75°C for 3h, and after centrifugal filtration, the precipitate is taken to obtain a filter cake;

[0037] Step 4: The filter cake is added to ethanol, and tetraethyl orthosilicate is added, and the temperature is raised to 45°C, and treated at a stirring speed of 200 rpm for 3h, and the resulting product is dried at 100°C for 1h, and then placed in a muffle furnace, and the temperature is raised to 580°C at a rate of 5°C / min, and calcined for 4h to obtain a second functional material.

[0038] In step 1, the mass of deionized water is equal to the total mass of sodium hydroxide and sodium carbonate, and the mass ratio of the mixture to the alkaline solution is 1:2, and in step 4, the mass ratio of the filter cake to ethanol is 1:3.

[0039] In step 4, the mass of tetraethyl orthosilicate is 8% of the mass of the filter cake.

[0040] In step 1, the raw materials of the base ceramic blank are composed of alumina, silica, and yttrium oxide, and the mass ratio of each raw material is 1.8:0.9:0.12.

[0041] In step 1, the raw materials of the base ceramic blank are composed of alumina, silica, and yttrium oxide, and the mass ratio of each raw material is 1.8:0.9:0.12.

[0042] In step 1, the raw materials of the base ceramic blank are composed of alumina, silica, and yttrium oxide, and the mass ratio of each raw material is 1.8:0.9:0.12.

[0043] S1: The base ceramic blank and calcium fluoride are mixed at a stirring speed of 50 rpm for 5 min to obtain a dry mixture;

[0044] S1: The first functional material, the second functional material, polyvinyl alcohol, anhydrous ethanol, and the dry mixture prepared in S1 are added to a ball mill for grinding treatment to obtain a wet grinding material;

[0045] S3: The wet grinding material is vacuum dried at 60°C for 12h, and the resulting product is sieved through a 100 mesh sieve to obtain a mixed powder;

[0046] S4: The mixed powder is loaded into a rubber mold and cold isostatic pressed at 200MPa for 5min to obtain a green blank;

[0047] S5: The green blank is heated to 300°C at a rate of 2°C / min in an atmosphere furnace for 2h, then transferred to a graphite mold, and heated to 1500°C at a rate of 5°C / min under argon protection for 4h to obtain a ceramic matrix composite material with an abradable coating.

[0048] Example 2:

[0049] A ceramic matrix composite material with an abradable coating is prepared from the following raw materials by weight: 85 parts of a base ceramic blank, 7 parts of a first functional material, 5 parts of a second functional material, 0.8 parts of calcium fluoride, 0.4 parts of polyvinyl alcohol, and 32 parts of anhydrous ethanol.

[0050] The first functional material is prepared by mixing glucose and deionized water in a mass ratio of 1:5, and then hydrothermally reacting at 200 DEG C for 11 hours under nitrogen protection, to obtain carbon microspheres.

[0051] The temperature is raised to 1500 DEG C at a rate of 9 DEG C / min, and the temperature is maintained for 2.5 hours under the protection of argon gas at a flow rate of 200 mL / min.

[0052] The mass ratio of the carbon microspheres, ethanol, zirconium oxychloride, and boric acid is 5:10:3.5:1.5.

[0053] The second functional material is prepared by:

[0054] Step 1: Sodium hydroxide and sodium carbonate are mixed in a mass ratio of 5:3, and then dissolved in deionized water to obtain an alkaline solution;

[0055] Step 2: Magnesium nitrate, aluminum nitrate, and copper nitrate are selected in a mass ratio of 5:3:1, and then put into a blender for stirring at a speed of 150 rpm for 45 minutes to obtain a mixture;

[0056] Step 3: The mixture obtained in Step 2 and the alkaline solution obtained in Step 1 are added to a reaction kettle, and then treated at a speed of 350 rpm and a temperature of 80 DEG C for 4 hours, and then the precipitate is obtained by centrifugal filtration to obtain a filter cake;

[0057] Step 4: The filter cake is added to ethanol, and then tetraethyl orthosilicate is added, and then the temperature is raised to 48 DEG C, and then stirred at a speed of 250 rpm for 3.5 hours, and then the obtained product is dried at a temperature of 100 DEG C for 1.5 hours, and then placed in a muffle furnace, and then the temperature is raised to 600 DEG C at a rate of 5 DEG C / min, and then calcined for 4.5 hours to obtain the second functional material.

[0058] In Step 1, the mass of deionized water is 1.5 times the total mass of sodium hydroxide and sodium carbonate, the mass ratio of the mixture to the alkaline solution is 1:2.5, and in Step 4, the mass ratio of the filter cake to ethanol is 1:4.

[0059] In Step 4, the mass of tetraethyl orthosilicate is 9% of the mass of the filter cake.

[0060] The raw materials of the base ceramic blank are composed of alumina, silicon dioxide and yttrium oxide, and the mass ratio of each raw material is 2:1:0.13.

[0061] The particle size of the alumina is 5 μm, the particle size of the silicon dioxide is 4 μm, and the particle size of the yttrium oxide is 1.5 μm.

[0062] The preparation method of the ceramic matrix composite material with an abradable coating comprises the following steps:

[0063] S1: The base ceramic blank and calcium fluoride are mixed at a stirring speed of 80 rpm for 8 min to obtain a dry mixture;

[0064] S1: The first functional material, the second functional material, polyvinyl alcohol, anhydrous ethanol and the dry mixture obtained in S1 are added into a ball mill for grinding treatment to obtain a wet grinding material;

[0065] S3: The wet grinding material is vacuum dried at 65℃ for 13 h, and the obtained product is sieved through a 100-mesh sieve to obtain a mixed powder;

[0066] S4: The mixed powder is loaded into a rubber mold and subjected to cold isostatic pressing at 200 MPa for 5 min to obtain a green blank;

[0067] S5: The green blank is heated to 300℃ at a heating rate of 2℃ in an atmosphere furnace for 2 h, and then is transferred into a graphite mold and heated to 1500℃ at a heating rate of 5℃ / min under argon protection for 4 h to obtain the ceramic matrix composite material with an abradable coating.

[0068] Example 3:

[0069] The ceramic matrix composite material with an abradable coating is composed of the following raw materials by weight: 90 parts of a base ceramic blank, 8 parts of a first functional material, 7 parts of a second functional material, 1 part of calcium fluoride, 0.5 part of polyvinyl alcohol, and 35 parts of anhydrous ethanol.

[0070] The preparation method of the first functional material is as follows: glucose and deionized water are mixed at a mass ratio of 1:6, and subjected to hydrothermal reaction at 220℃ for 12 h, in the process, nitrogen gas is introduced for protection, to obtain carbon microspheres, which are dispersed in ethanol, and then zirconium oxychloride and boric acid are added, and stirred at 65℃ and 110 rpm for 8 h, and the obtained product is dried to obtain a powder material, which is calcined in a tubular atmosphere furnace to obtain the first functional material.

[0071] When the tubular atmosphere furnace is used, the heating rate is set to 10℃ / min, the temperature is raised to 1550℃, and the holding time is 3 h, in the process, argon gas is introduced, and the argon gas flow is 200 mL / min.

[0072] The mass ratio of the carbon microspheres, ethanol, zirconium oxychloride, and boric acid is 5:11:4:2.

[0073] The preparation method of the second functional material is as follows:

[0074] Step 1: sodium hydroxide and sodium carbonate are mixed in a mass ratio of 5:3 and then dissolved in deionized water to prepare an alkaline solution;

[0075] Step 2: magnesium nitrate, aluminum nitrate, and copper nitrate are selected in a mass ratio of 5:3:1, and then put into a blender for processing at a stirring speed of 200 rpm for 60 min to obtain a mixture;

[0076] Step 3: the mixture prepared in Step 2 and the alkaline solution prepared in Step 1 are added into a reaction kettle, and then processed at a stirring speed of 400 rpm and 85°C for 5 h. After centrifugal filtration, the precipitate is obtained to obtain a filter cake;

[0077] Step 4: the filter cake is added into ethanol, and then tetraethyl orthosilicate is added. The temperature is raised to 50°C, and then processed at a stirring speed of 300 rpm for 4 h. The obtained product is dried at 100°C for 2 h, and then placed into a muffle furnace. The temperature is raised to 620°C at a temperature raising rate of 5°C / min, and then calcined for 5 h to prepare the second functional material.

[0078] In Step 1, the mass of deionized water is 2 times the total mass of sodium hydroxide and sodium carbonate. The mass ratio of the mixture and the alkaline solution is 1:3. In Step 4, the mass ratio of the filter cake and ethanol is 1:5.

[0079] In Step 4, the mass of tetraethyl orthosilicate is 10% of the mass of the filter cake.

[0080] The raw materials of the basic ceramic blank consist of alumina, silicon dioxide, and yttrium oxide, and the mass ratio of each raw material is 2.2:1.1:0.14.

[0081] The particle size of the alumina is 6 μm, the particle size of the silicon dioxide is 5 μm, and the particle size of the yttrium oxide is 2 μm.

[0082] The preparation method of the ceramic matrix composite material with an abradable coating comprises the following steps:

[0083] S1: the basic ceramic blank and calcium fluoride are mixed at a stirring speed of 100 rpm for 10 min to obtain a dry mixture;

[0084] S1: the first functional material, the second functional material, polyvinyl alcohol, anhydrous ethanol, and the dry mixture prepared in S1 are added into a ball mill for grinding processing to obtain a wet mixture;

[0085] S3: the wet mixture is vacuum dried at 70°C for 14 h. The obtained product is sieved through a 100-mesh sieve to obtain a mixed powder;

[0086] S4: The mixed powder was loaded into a rubber mold and cold isostatic pressing was performed at 200 MPa for 5 min to obtain a green compact;

[0087] S5: The green compact was heated to 300 °C at a rate of 2 °C / min in an atmosphere furnace for 2 h, and then was transferred into a graphite mold and heated to 1500 °C at a rate of 5 °C / min under argon protection for 4 h to obtain a ceramic matrix composite material with an abradable coating.

[0088] Comparative Example 1, the difference between this comparative example and Example 1 is that the first functional material is not contained in this comparative example.

[0089] Comparative Example 2, the difference between this comparative example and Example 1 is that the second functional material is not contained in this comparative example.

[0090] Comparative Example 3, the difference between this comparative example and Example 1 is that the first functional material and the second functional material are not contained in this comparative example.

[0091] Performance test: Commercial alumina ceramic valves were selected, and after surface sandblasting treatment, alcohol cleaning was performed, and then the composite materials prepared by Examples 1-3 and Comparative Examples 1-3 were used to form a coating layer of 800 μm by supersonic flame spraying to obtain test samples, and the leakage rate, wear life, and thermal shock times of the test samples were tested.

[0092] The obtained test data are recorded in the following table:

[0093]

[0094] Leakage rate test: GB / T13927-2018 standard was used to test the leakage rate.

[0095] Wear life test: GB / T45593-2025 standard was used to test the simulated wear life.

[0096] Thermal shock cycle test: the thermal shock resistance of the coating was evaluated by a cyclic thermal shock test method. The sample was placed in a high-temperature resistance furnace and heated to 1000 °C at a rate of 10 °C / min, and then was immediately immersed in deionized water at 25±2 °C for rapid cooling for 30 seconds. Then, the sample was taken out and air-dried, and the process was cycled. The coating surface was regularly checked with a 40x microscope, and the cycle number when obvious cracks or coating peeling occurred was recorded.

[0097] By analyzing and comparing the data in the table, it can be seen that the test data of Examples 1-3 are better than those of Comparative Examples 1-3.

[0098] This shows that: in the first functional material, the through-hole network precisely controlled by the carbon microsphere template constructs a three-dimensional elastic stress buffer system in the ceramic matrix. When the ceramic valve sealing surface bears high pressure impact, the directional bending of the hole wall in the buffer system converts the point-like concentrated stress into distributed deformation, effectively absorbs the stress wave energy, and in the thermal shock working condition, the micro-gap layer formed between the hole walls in the instant cooling blocks the heat conduction path, so that the expansion difference caused by the temperature gradient is gradually resolved by thousands of micro-hole units, and the curled whiskers formed by the anisotropic growth of the calcined zirconium boride crystals along the hole channel produce a bridging effect, which, under the mutual coordination, changes the brittle and hard characteristics of traditional ceramics like glass into flexible characteristics, and fundamentally solves the problem of thermal shock failure of ceramic coatings;

[0099] In the preparation process of the second functional material, the directional assembly of the magnesium-aluminum-copper ternary precursor in the alkaline solution forms a hydrotalcite-like matrix with a nano-layered structure, in which copper ions are precisely anchored between the lattice layers, and tetraethyl orthosilicate is hydrolyzed and condensed in the ethanol environment to form a silica coating layer, and a thermal expansion and contraction memory effect is generated during heat treatment, so that the sealing is kept intact at room temperature to avoid loss of active components. When the friction temperature rises above the critical point, micron-level grid cracks occur in the layer to release the molten copper compound to form a self-healing film, while the magnesium component forms the main lattice network to give the structure strength, and the aluminum component optimizes the thermal stability of the material to prevent high-temperature inactivation. The interface reaction between aluminum and the silicon shell generates mullite buffer phase, which not only maintains the integrity of the coating layer but also controls the copper release rate, achieving a dynamic balance between wear and repair, forming a negative feedback mechanism that gets more protection with more wear, so that the material has an abradable property, solving the problem of passive protection of traditional ceramic coatings.

[0100] When the first functional material acting as a honeycomb framework and the second functional material forming core-shell particles act on the matrix, the boron-oxygen active sites on the inner wall of the zirconium boride hole form a stable magnesium borate bonding interface with the magnesium oxide surface layer of the core-shell particles, thereby presenting a memory effect in thermal shock cycles. Under friction conditions, the lubricating phase overflowing from the pores is filtered again by the honeycomb structure, forming an ultra-pure repair film after removing impurities, and the two achieve material and energy exchange through chemical bonds. This biomimetic synergy enables the coating to have material reconstruction properties, greatly improving the comprehensive performance of ceramic products.

[0101] Through comparison and analysis of the related data in the table, it can be seen that the chlorinated fatty acid methyl ester composite PVC plasticizer prepared by the application not only solves the disadvantages of the brittle and hard characteristics of ceramics, but also solves the problem of passive protection of traditional ceramic coatings. Therefore, the chlorinated fatty acid methyl ester composite PVC plasticizer preparation process provided by the application has a broader market prospect and is more suitable for promotion.

[0102] In the description of the specification, reference to "one embodiment", "an example", "a specific example" or the like means that a particular feature, structure, material or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. The appearances of the phrases "in one embodiment", "an example", "a specific example" or the like in various places in the specification are not necessarily referring to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0103] The preferred embodiments of the application disclosed above are only to help explain the application. The preferred embodiments do not describe all the details of the application and limit the application to the specific embodiments described. Obviously, many modifications and variations can be made in light of the contents of the specification. The specification selects and specifically describes these embodiments in order to better explain the principles and practical application of the application, so that those skilled in the art can well understand and utilize the application. The application is limited only by the claims and their full scope and equivalents.

Claims

1. A ceramic matrix composite material for wearable coatings, characterized in that: It is composed of the following raw materials in parts by weight: 80-90 parts of basic ceramic blank, 6-8 parts of first functional material, 4-7 parts of second functional material, 0.5-1 part of calcium fluoride, 0.3-0.5 parts of polyvinyl alcohol, and 30-35 parts of anhydrous ethanol; The preparation method of the first functional material is as follows: glucose and deionized water are mixed at a mass ratio of 1: (5-6) and hydrothermally reacted at 180-220℃ for 10-12 hours, with nitrogen gas introduced for protection during the process, to obtain carbon microspheres. The carbon microspheres are dispersed in ethanol, and zirconium oxychloride and boric acid are added. The mixture is stirred at 55-65℃ and 80-110 rpm for 6-8 hours. The resulting product is dried to obtain powder material. The powder material is placed in a tube furnace for calcination to obtain the first functional material. When using the tubular atmosphere furnace, the heating rate is set to 8-10℃ / min, the temperature is raised to 1450-1550℃, and the holding time is 2-3h. Argon gas is introduced during the process, and the argon gas flow rate is 200mL / min. The mass ratio of the carbon microspheres, ethanol, zirconium oxychloride and boric acid is 5:(9-11):(3-4):(1-2); The raw materials of the basic ceramic blank are composed of alumina, silicon dioxide and yttrium oxide, and the mass ratio of each raw material is (1.8~2.2):(0.9~1.1):(0.12~0.14).

2. The ceramic matrix composite material for wearable coatings according to claim 1, characterized in that, The preparation method of the second functional material is as follows: Step 1: Mix sodium hydroxide and sodium carbonate in a mass ratio of 5:3 and dissolve in deionized water to obtain an alkaline solution; Step 2: Select magnesium nitrate, aluminum nitrate, and copper nitrate in a mass ratio of 5:3:1, add them to a mixer, and process them at a stirring speed of 100-200 rpm for 30-60 minutes to obtain a mixture; Step 3: Add the mixture obtained in Step 2 and the alkaline solution obtained in Step 1 to the reactor, and treat it at 300-400 rpm and 75-85℃ for 3-5 hours. After centrifugation and filtration, take the precipitate to obtain the filter cake. Step 4: Add the filter cake to ethanol, then add tetraethyl orthosilicate, heat to 45-50℃, and stir at 200-300 rpm for 3-4 hours. Dry the resulting product at 100℃ for 1-2 hours, then place it in a muffle furnace and calcine at 580-620℃ for 4-5 hours with a heating rate of 5℃ / min to obtain the second functional material.

3. The ceramic matrix composite material for wearable coatings according to claim 2, characterized in that, In step 1, the mass of deionized water is 1 to 2 times the total mass of sodium hydroxide and sodium carbonate, the mass ratio of the mixture to the alkaline solution is 1:(2 to 3), and the mass ratio of the filter cake to ethanol in step 4 is 1:(3 to 5).

4. The ceramic matrix composite material for wearable coatings according to claim 2, characterized in that, In step 4, the mass of tetraethyl orthosilicate is 8-10% of the filter cake mass.

5. The ceramic matrix composite material for wearable coatings according to claim 1, characterized in that, The alumina has a particle size of 4–6 μm, the silica has a particle size of 3–5 μm, and the yttrium oxide has a particle size of 1–2 μm.

6. A method for preparing a ceramic matrix composite material for a wearable coating, characterized in that, The preparation of a ceramic matrix composite material for a wearable coating according to any one of claims 1-5 comprises the following steps: S1: Mix the basic ceramic blank and calcium fluoride at a stirring speed of 50-100 rpm for 5-10 minutes to obtain a dry mixture; S1: The first functional material, the second functional material, polyvinyl alcohol, anhydrous ethanol and the dry mixture obtained in S1 are added to a ball mill for grinding to obtain wet abrasive. S3: The wet abrasive is vacuum dried at 60-70℃ for 12-14 hours, and the resulting product is passed through a 100-mesh sieve to obtain a mixed powder; S4: The mixed powder is loaded into a rubber mold and subjected to cold isostatic pressing at 200MPa for 5 minutes to obtain a raw blank. S5: The raw material is heated to 300℃ in an atmosphere furnace at a heating rate of 2℃ and held for 2 hours. Then it is transferred to a graphite mold and heated to 1500℃ at a heating rate of 5℃ / min under argon protection and held for 4 hours to obtain a ceramic matrix composite material with a wearable coating.

7. An application of a ceramic matrix composite material for a wearable coating as described in any one of claims 1-5, characterized in that, Application in coatings for sealing surfaces of high-temperature ceramic valves.

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