A cold-spray ceramic coating and its preparation method

Abstract

This invention discloses a cold-spray ceramic coating and its preparation method; the primer contains 26-28% silica sol, 4-5% 1% NaOH solution, 10-12% pigment, 8-10% filler, 4-5% hydroxyethyl cellulose aqueous solution, 1-1.5% dispersant, 20-22% methyltrimethoxysilane, 5-6% acetic acid, 1-2% leveling agent, 1-2% organotitanium crosslinking agent, 1-2% wetting agent, and the balance of deionized water; the topcoat contains 38-40% silica sol, 30-32% methyltrimethoxysilane, 5-6% acetic acid, 3-4% leveling agent, 3-4% non-sticking agent, 1-2% organotitanium crosslinking agent, 1-2% wetting agent, and the balance of deionized water. The organic titanium crosslinking agent added to the ceramic system undergoes a crosslinking reaction with -OH in the system. By adjusting the pH to between 4.4 and 4.9 after the ceramic coating is cured, a cold-sprayable ceramic coating is prepared. After spraying at room temperature, the paint film achieves the effect of leveling and crosslinking at the same time. After crosslinking, the paint film loses its fluidity, and even if the substrate is suspended for spraying, there will be no sagging.

Description

Technical Field

[0001] This invention belongs to the field of ceramic materials technology, specifically relating to a cold-spray ceramic coating and its preparation method. Background Technology

[0002] Ceramic coatings are typically produced using the sol-gel method, where organic and inorganic substances react to form a water-based coating that combines the advantages of both. They are primarily used in cookware, small appliances, and curtain wall panels. While ceramic coatings possess excellent properties such as high hardness, good wear resistance, non-flammability, smokelessness, and environmental friendliness, their application process is relatively complex. For example, as water-based coatings, they have low viscosity and are prone to sagging during application. To prevent sagging, the substrate must be preheated to 45-60℃. Preheating temperature must be accurately controlled; too high a temperature will cause the paint film to dry out, resulting in poor leveling and affecting the coating's appearance and performance; too low a temperature will result in insufficient paint film thickness, also affecting coating performance. This process demands skilled application personnel and increases costs for users. Compared to organic coatings, the application is extremely inconvenient, severely hindering the use and promotion of ceramic coatings.

[0003] Based on the above problems, there is an urgent need to solve the process of preheating the substrate before applying ceramic coatings, and to invent a ceramic coating that can be cold-sprayed.

[0004] A search of existing patent literature revealed that authorized invention patent CN202210182024.8 discloses a ceramic coating that can be applied at room temperature and has low unit consumption, as well as its preparation and application method, which solves the problem of room temperature application by increasing the viscosity of the ceramic coating and adding a thixotropic agent. CN201510332612.5 discloses a ceramic film coating that can be sprayed at room temperature, which solves the problem of room temperature application by adding an anti-sagging agent. The principles of the above two patents in solving the problem of room temperature application of ceramic coatings are basically the same, which is to prevent sagging by increasing the viscosity of the coating and reducing the leveling time of the coating. However, the above technical solutions will bring a series of defects: (1) due to the high viscosity of the coating and the short leveling time, the smoothness of the coating is not good, which will affect the appearance and decoration of the coating; (2) the added anti-sagging agent or thixotropic agent will reduce the gloss of the coating, which will also affect the appearance and decoration of the coating. Summary of the Invention

[0005] The purpose of this invention is to overcome the inconvenience of preheating the substrate to 45-60℃ during the application of ceramic coatings in the prior art, and to address the problems of poor coating smoothness and insufficient gloss caused by increasing the viscosity of the coating and reducing the leveling time to prevent sagging during room temperature application. This invention provides a cold-spray ceramic coating and its preparation method. The cold-spray ceramic coating of this invention can be applied using the same method as organic coatings. The substrate does not require preheating before application and can be sprayed directly. Even when the substrate is suspended during spraying, sagging does not occur, and the smoothness and gloss of the coating are not affected.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] <First Aspect>

[0008] This invention provides a cold-spray ceramic coating having a primer and a topcoat;

[0009] Based on 100% of the total mass of the primer, the primer composition is as follows: silica sol: 26-28%, 1% NaOH solution: 4-5%, pigment: 10-12%, filler: 8-10%, hydroxyethyl cellulose aqueous solution: 4-5%, dispersant: 1-1.5%, methyltrimethoxysilane: 20-22%, acetic acid: 5-6%, leveling agent: 1-2%, organotitanium crosslinking agent: 1-2%, organotitanium crosslinking agent wetting agent: 1-2%, and deionized water: balance;

[0010] Based on 100% of the total mass of the topcoat, the composition of the topcoat is as follows: silica sol: 38-40%, methyltrimethoxysilane: 30-32%, acetic acid: 5-6%, leveling agent: 3-4%, non-sticking agent: 3-4%, organotitanium crosslinking agent: 1-2%, organotitanium crosslinking agent wetting agent: 1-2%, and deionized water: balance.

[0011] As one implementation, the organic titanium crosslinking agent is selected from aqueous titanate complexes.

[0012] As one embodiment, the wetting agent for the organic titanium crosslinking agent is isopropanol, and the mass ratio of isopropanol to the organic titanium crosslinking agent is 1:1.

[0013] As one implementation, the primer is divided into components A and B. Component A of the primer is a mixture of the organic titanium crosslinking agent and the organic titanium crosslinking agent wetting agent, and the remaining components belong to component B of the primer.

[0014] And / or, the topcoat is divided into components A and B, with component A being a mixture of the organic titanium crosslinking agent and a wetting agent for the organic titanium crosslinking agent, and the remaining components belonging to component B.

[0015] As one embodiment, the pH of primer component B is 4.4-4.9;

[0016] And / or, the pH of component B of the topcoat is 4.4-4.9.

[0017] As one embodiment, the concentration of the hydroxyethyl cellulose aqueous solution is 3 wt%.

[0018] As one implementation, deionized water is heated to above 20°C, and hydroxyethyl cellulose is added while stirring until it becomes a uniform and transparent solution, thus obtaining the hydroxyethyl cellulose aqueous solution.

[0019] <Second aspect>

[0020] The present invention also provides a method for preparing the aforementioned cold-spray ceramic coating, the method comprising the following steps:

[0021] Primer preparation:

[0022] S1. Mix the organic titanium crosslinking agent with a wetting agent until uniform to obtain primer component A, which is ready for use.

[0023] S2. Mix the silica sol, 1% NaOH solution, pigment, filler, and dispersant evenly, grind to a fineness of less than 20 μm, test the pH value of the color paste, and if it is less than 9.5, adjust it to 9.5-10 with 1% NaOH solution; add the hydroxyethyl cellulose aqueous solution, stir evenly to obtain the color paste, and set aside for use;

[0024] S3. Mix the methyltrimethoxysilane, acetic acid, leveling agent, and deionized water evenly, then add the color paste and mix well to obtain ceramic primer component B.

[0025] And / or, topcoat preparation:

[0026] S4. Mix the organic titanium crosslinking agent with the organic titanium crosslinking agent evenly with a wetting agent to obtain topcoat component A, which is ready for use.

[0027] S5. Mix the methyltrimethoxysilane, acetic acid, leveling agent, non-sticking agent, and deionized water evenly, then add silica sol and mix well to obtain ceramic topcoat component B.

[0028] As one implementation, in steps S3 and S5, the mixing is carried out under the condition of rolling at 120-150 rpm for 6-8 hours.

[0029] <Third aspect>

[0030] The present invention also provides a method for applying the aforementioned cold-spray ceramic coating, the method comprising the following steps:

[0031] A1. After mixing the primer components A and B evenly, spray them onto the substrate surface;

[0032] A2. After the primer is applied, mix the topcoat components A and B evenly, and then spray the topcoat onto the primer surface using a wet-on-wet method.

[0033] A3. Low temperature: 80-100℃ × 5-8 minutes; High temperature: 230-260℃ × 10-15 minutes, to complete curing.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) An organic titanium crosslinking agent was added to the ceramic coating formulation, which can undergo a crosslinking reaction with -OH in the ceramic coating system. By adjusting the pH of the ceramic coating after aging to between 4.4 and 4.9, a cold-sprayable ceramic coating was prepared. After spraying at room temperature, the paint film achieves the effect of leveling and crosslinking at the same time. After crosslinking, the paint film loses its fluidity. Even if the substrate is suspended for spraying, there will be no sagging.

[0036] (2) Since the organic titanium crosslinking agent is a crosslinking agent for -OH and -COOH systems, after crosslinking reaction with inorganic metal substrates and ceramic coating systems, it can improve the adhesion between ceramic coatings and substrates, and improve the crosslinking density and water resistance of the coating. Since the paint film has good leveling at the same time as the crosslinking reaction, the paint film has a smooth appearance and the gloss is not affected. Detailed Implementation

[0037] The present invention will be described in detail below with reference to embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several adjustments and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0038] The cold-spray ceramic coating of the present invention consists of two layers: a primer and a topcoat. The primer is a colored paint, and its composition, based on 100% of the total mass of the primer, is as follows: silica sol: 26-28%, 1% NaOH solution: 4-5%, pigment: 10-12%, filler: 8-10%, 3wt% hydroxyethyl cellulose aqueous solution: 4-5%, dispersant: 1-1.5%, methyltrimethoxysilane: 20-22%, acetic acid: 5-6%, leveling agent: 1-2%, organotitanium crosslinking agent: 1-2%, the organotitanium crosslinking agent is a wetting agent (isopropanol), and the mass ratio of isopropanol to the organotitanium crosslinking agent is 1:1-1:1.5, deionized water: balance.

[0039] in,

[0040] Silica sol: The main film-forming substance in ceramic coatings, rich in -OH groups on the surface, and commonly available commercial products, such as AkzoNobel's Bindzil 2034DI, Nissan Chemical's ST-O-40, and Grace. HS-40, etc.

[0041] 1% NaOH solution: pH adjuster for color paste. The pH value of color paste will decrease slightly during grinding and storage. When the pH value drops below 8.5 and approaches neutral, the silica sol will gel and cause the color paste to deteriorate. Therefore, before grinding, the pH value of color paste needs to be adjusted to between 9.5 and 10.5 with an alkaline solution. After grinding, the pH value of color paste should be adjusted to above 9.5 to ensure that the color paste will not deteriorate due to the decrease in pH value during storage.

[0042] Pigments: Give coatings different colors. Common inorganic pigments are selected because they have good temperature resistance and safety. Examples include titanium dioxide, manganese iron black, iron oxide yellow, iron oxide red, and cobalt blue.

[0043] Fillers: They play a role in reducing the cost of coatings and increasing the solid content of coatings. Commonly used fillers are selected, such as mica powder, silicon micro powder, silicon carbide, alumina powder, talc powder, etc.

[0044] 3-3.5wt% hydroxyethyl cellulose aqueous solution: A relatively mild water-based paint thickener with minimal viscosity variation within a pH range of 2-12. It can adjust the viscosity of ceramic coatings, exhibiting excellent transparency and leveling properties. Its molecular chain surface is rich in -OH groups, allowing it to undergo cross-linking reactions with organotitanium cross-linking agents. Since ceramic coating pigments are alkaline (approximately 8.5-10) and finished ceramic coatings are acidic (4.4-4.9), the pH value varies significantly. Using other types of cellulose would result in large viscosity changes due to pH variations, making application impossible. Furthermore, if the hydroxyethyl cellulose concentration is below 3%, the viscosity adjustment effect is poor, requiring a larger amount, which reduces the solids content of the coating, leading to poor abrasion resistance and consequently affecting non-stick durability. If the hydroxyethyl cellulose concentration is above 3.5%, the coating viscosity increases excessively, causing spray gun clogging and poor workability. Additionally, insufficient leveling time means the coating cross-links before fully leveling, resulting in low gloss and poor decorative properties.

[0045] Dispersants: They reduce the dispersion time of pigments and fillers, stabilize pigment dispersions, and improve the tinting strength and hiding power of pigments. Examples include BYK180, BYK190, BYK2010, and BYK2001.

[0046] Methyltrimethoxysilane: A film-forming aid. On the one hand, methyltrimethoxysilane has a fast hydrolysis and polymerization rate, which can shorten the reaction time of ceramic coatings and improve the curing efficiency of ceramic coatings. On the other hand, Si is connected to three -OCH3 groups, and after hydrolysis, it forms three silanol groups (Si-OH). After polymerization with silica sol, it can form a coating with a three-dimensional cross-linked structure. The coating has a dense structure and is not easy to crack.

[0047] Acetic acid: a catalyst for the sol-gel reaction in ceramic coatings, adjusting the pH value of the ceramic coating after the reaction to between 4.4 and 4.9. Methyltrimethoxysilane undergoes hydrolysis under acidic conditions and then condenses with silica sol to produce ceramic coatings. Due to the different acidities and catalytic efficiencies of various acids, if formic acid, citric acid, benzoic acid, hydrochloric acid, or other acids are used instead at the specified dosage in this formulation, the pH of the aged ceramic coating will be <4.0, or even lower. This results in a very short usable time for the ceramic coating, typically <12 hours, and the paint film will dry out. Furthermore, the crosslinking reaction rate of the organotitanium crosslinking agent is too fast, leading to poor leveling and low gloss of the coating.

[0048] Leveling agents: These promote the formation of a smooth, even, and uniform coating film during the drying process. Examples include BYK-333 and Dow Corning DC-57.

[0049] Organic titanium crosslinking agents: These are environmentally friendly crosslinking agents and adhesion promoters for water-based coatings. They can undergo crosslinking reactions with various types of resins containing -OH and -COOH groups, improving the crosslinking density, adhesion, and water resistance of water-based systems. For example: DuPont. TM 371, etc. It can be stored stably in aqueous solutions with a pH of 7–8. However, when the pH is <6, >8, or the temperature is >100°C, [it may cause problems]. 371 undergoes a cross-linking reaction, and the reaction rate varies with pH or temperature. And if... TPT reacts with water to form titanic acid, which affects the pH of the coating and is therefore unsuitable for the system described in this invention.

[0050] In ceramic coating systems, the main film-forming substance, silica sol, has a surface rich in -OH groups. The auxiliary film-forming substance, methyltrimethoxysilane, forms silanol (-SiOH) after acidic hydrolysis. Additionally, the thickener, hydroxyethyl cellulose, also has a molecular chain rich in -OH groups. Therefore, the organotitanium crosslinking agent can undergo a full crosslinking reaction with the ceramic coating system to play its role.

[0051] Isopropanol: An organic solvent, used as a special wetting agent for organotitanium crosslinking agents. It is mixed with organotitanium crosslinking agents at a mass ratio of 1:1 to improve compatibility with water-based coatings.

[0052] In the cold-spray ceramic coating of the present invention, the topcoat is colorless and transparent. Based on 100% of the total mass of the topcoat, the composition of the topcoat is as follows: silica sol: 38-40%, methyltrimethoxysilane: 30-32%, acetic acid: 5-6%, leveling agent: 3-4%, non-sticking agent: 3-4%, organotitanium crosslinking agent: 1-2%, the organotitanium crosslinking agent is a wetting agent (isopropanol), and the mass ratio of isopropanol to organotitanium crosslinking agent is 1:1-1.5:1, deionized water: balance.

[0053] In the topcoat,

[0054] Non-stick additives: These improve the feel, non-stick properties, and ease of cleaning of the coating. Non-stick additives with hydroxyl groups at the ends of their molecular chains are preferred. These additives can participate in the reaction during the curing process of the ceramic coating, chemically bonding to the molecular chain and providing a more durable non-stick effect. Commonly available products include: 3600 from Guangzhou Hanju Polymer Materials Co., Ltd., and K-766 from Guangdong Biaomei Fluorosilicone New Materials Co., Ltd.

[0055] The preparation steps of the primer for the cold-spray ceramic coating of the present invention are as follows:

[0056] (1) Preparation of 3wt% hydroxyethyl cellulose aqueous solution: Weigh 97g of deionized water and 3g of hydroxyethyl cellulose. First, heat the deionized water to above 35°C. Then, gradually add the hydroxyethyl cellulose while stirring until it becomes a uniform and transparent solution. Set aside for use.

[0057] Hydroxyethyl cellulose has low solubility (<5 wt%) in cold water and dissolves slowly, but its solubility is significantly improved in hot water. Once completely dissolved, it forms a colorless and transparent solution and will not affect the color of the coating.

[0058] (2) Preparation of color paste: Mix silica sol, 1% NaOH solution, pigment, filler and dispersant evenly, grind to a fineness of less than 20μm on a basket mill, test the pH value of the color paste, if it is less than 9.5, adjust to 9.5-10 with 1% NaOH solution, then add 3wt% hydroxyethyl cellulose aqueous solution, stir evenly and set aside for use.

[0059] The pH value of ceramic coating pigments will slightly decrease during grinding and storage. The degree of pH decrease varies depending on the color of the pigment. When the pH value of the pigment drops below 8.5 and approaches neutral, the silica sol will gel, leading to pigment deterioration. Therefore, it is necessary to adjust the pH value of the ground pigment to 9.5-10 with an alkaline solution to ensure that the pigment does not deteriorate due to pH decrease during storage. Hydroxyethyl cellulose exhibits minimal viscosity change within a pH range of 2-12, resulting in pigments with minimal viscosity variation, stability, and resistance to sedimentation.

[0060] (3) Mix the organic titanium crosslinking agent and isopropanol at a weight ratio of 1:1 and set aside. The organic titanium crosslinking agent and isopropanol can improve the compatibility and stability with the water-based coating system. If the organic titanium crosslinking agent is added directly to the water-based coating, the coating will be layered, the crosslinking reaction will be insufficient, the curing speed of the coating will be slow, the adhesion will be slightly poor, and the water resistance will be poor.

[0061] (4) Mix methyltrimethoxysilane, acetic acid, leveling agent and deionized water evenly, then add the color paste from step (2), and roll at 120-150 rpm for 6-8 hours to obtain ceramic primer with pH 4.4-4.9.

[0062] The solution from step (3) must be mixed evenly with the primer before application. Since the organotitanium crosslinking agent is a rapid crosslinking curing agent for -OH and -COOH systems, and since the film-forming substances in ceramic coatings, silica sol and methyltrimethoxysilane, both have -OH groups after hydrolysis, and the surface of hydroxyethyl cellulose molecules is also rich in -OH, the organotitanium crosslinking agent can undergo a crosslinking reaction with the ceramic coating system. Its crosslinking reaction rate is related to the pH of the system. Experiments have shown that when the pH is between 4.4 and 4.9, the sprayed paint film can achieve the effect of simultaneous leveling and crosslinking reaction. After crosslinking, the paint film loses its fluidity, and even if the substrate is suspended during spraying, there will be no sagging. When the pH is higher than 4.9, the crosslinking speed is slow, resulting in slight sagging and uneven film thickness during suspended spraying; when the pH is lower than 4.4, the crosslinking speed is too fast, resulting in poor leveling and low gloss.

[0063] Since a certain amount of -OH groups exist on the surface of inorganic metal substrates after sandblasting, organic titanium crosslinking agents can also undergo crosslinking reactions with the -OH groups on the substrate surface, thereby improving the adhesion of the paint film.

[0064] The preparation steps of the transparent topcoat of the cold-spray ceramic coating of the present invention are as follows:

[0065] (1) Mix the organic titanium crosslinking agent and isopropanol at a weight ratio of 1:1 until homogeneous and set aside;

[0066] (2) Mix methyltrimethoxysilane, acetic acid, leveling agent, non-sticking agent and deionized water evenly, then add silica sol, and roll at 120-150 rpm for 6-8 hours to obtain ceramic topcoat. The pH value is tested to be 4.4-4.9.

[0067] The topcoat application method is the same as the primer application method. The solution in step (1) must be mixed evenly with the topcoat before application and then applied immediately. Otherwise, they must be stored separately.

[0068] Examples 1-4

[0069] Examples 1-4 provide a cold-spray ceramic coating consisting of two layers: a primer and a topcoat. The primer is a colored paint, and the topcoat is transparent. Its composition is shown in Table 1. The 3wt% hydroxyethyl cellulose aqueous solution is prepared as follows: 97g of deionized water and 3g of hydroxyethyl cellulose are weighed. The deionized water is first heated to above 20°C, and then the hydroxyethyl cellulose is gradually added while stirring until a uniform and transparent solution is obtained. This solution is then set aside for use.

[0070] The preparation steps of the primer for the cold-spray ceramic coating of the present invention are as follows:

[0071] Preparation of primer component A: Mix the organic titanium crosslinking agent and isopropanol at a weight ratio of 1:1 until homogeneous, and set aside for later use.

[0072] Preparation of primer component B:

[0073] (1) Preparation of color paste: Mix silica sol, 1% NaOH solution, pigment, filler and dispersant evenly, grind to a fineness of less than 20μm on a basket mill, test the pH value of the color paste, if it is less than 9.5, adjust to 9.5-10 with 1% NaOH solution, then add 3wt% hydroxyethyl cellulose aqueous solution, stir evenly and set aside for use.

[0074] (2) Mix methyltrimethoxysilane, acetic acid, leveling agent and deionized water evenly, then add the color paste from step (1), and roll at 120 rpm for 7 hours to obtain ceramic primer component B with pH 4.4-4.9.

[0075] The preparation steps for the topcoat are as follows:

[0076] Preparation of component A of topcoat: Mix the organic titanium crosslinking agent and isopropanol at a weight ratio of 1:1 until homogeneous, and set aside for use.

[0077] Preparation of topcoat component B: Methyltrimethoxysilane, acetic acid, leveling agent, non-sticking agent and deionized water were mixed evenly, and then silica sol was added. After rolling at 120 rpm for 7 hours, ceramic topcoat component B was obtained. The pH was tested to be 4.4-4.9.

[0078] Comparative Examples 1-7

[0079] Comparative Examples 1-7 provide a ceramic coating with the composition shown in Table 1; the preparation is the same as in Example 1. The preparation of the 3wt% aqueous solution of hydroxymethyl cellulose, the 3wt% aqueous solution of carboxyethyl cellulose, and the 3wt% aqueous solution of hydroxypropyl methyl cellulose is also the same as in Example 1.

[0080] Table 1. Coating composition and dosage (wt.%) of the examples and comparative examples

[0081]

[0082]

[0083] Main performance tests

[0084] The coatings prepared in the above embodiments and comparative examples were applied using the following methods, and their main performance was then tested. The application process is as follows:

[0085] After mixing the primer components A and B evenly, immediately pour the mixture into a spray gun paint container and spray it onto the substrate surface within 1 minute.

[0086] After the primer is applied, mix the topcoat components A and B evenly and immediately pour them into another spray gun's paint container. Within 1 minute, spray the topcoat onto the primer surface using a wet-on-wet method.

[0087] The coated workpiece is placed in an oven for curing: low temperature: 80-100℃ for 5-8 minutes; high temperature: 230-260℃ for 10-15 minutes. After natural cooling, performance testing is performed. The primer thickness is 30-35μm, and the topcoat thickness is 5-8μm.

[0088] The testing items and methods involved in the main performance tests of the coating are shown in Table 2:

[0089] Table 2

[0090]

[0091] The test results are shown in Table 3:

[0092] Table 3

[0093]

[0094] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A cold-spray ceramic coating comprising a primer and a topcoat, characterized in that, Based on 100% of the total mass of the primer, the primer composition is as follows: silica sol: 26-28%, 1% NaOH solution: 4-5%, pigment: 10-12%, filler: 8-10%, hydroxyethyl cellulose aqueous solution: 4-5%, dispersant: 1-1.5%, methyltrimethoxysilane: 20-22%, acetic acid: 5-6%, leveling agent: 1-2%, organotitanium crosslinking agent DuPont™ Tyzor® 371: 1-2%, isopropanol: 1-2%, and deionized water: balance; Based on 100% of the total mass of the topcoat, the topcoat composition is as follows: silica sol: 38-40%, methyltrimethoxysilane: 30-32%, acetic acid: 5-6%, leveling agent: 3-4%, non-stick additive: 3-4%, organotitanium crosslinking agent DuPont™ Tyzor® 371: 1-2%, isopropanol: 1-2%, and deionized water: balance; The concentration of the hydroxyethyl cellulose aqueous solution is 3-3.5 wt%; The primer is divided into components A and B. Component A is a mixture of the organic titanium crosslinking agent DuPont™ Tyzor® 371 and isopropanol, and the remaining components belong to component B. The pH of component B is 4.4-4.

9. The topcoat is divided into components A and B. Component A is a mixture of the organic titanium crosslinking agent DuPont™ Tyzor® 371 and isopropanol, and the remaining components belong to component B. The pH of component B is 4.4-4.

9.

2. The cold-spray ceramic coating according to claim 1, characterized in that, In the primer and topcoat, the mass ratio of isopropanol to the organotitanium crosslinking agent DuPont™ Tyzor® 371 is 1:1 to 1.5:

1.

3. The cold-spray ceramic coating according to claim 1, characterized in that, Deionized water is heated to above 20°C, and hydroxyethyl cellulose is added while stirring until it becomes a uniform and transparent solution, thus obtaining the hydroxyethyl cellulose aqueous solution.

4. A method for preparing a cold-sprayed ceramic coating according to any one of claims 1-3, characterized in that, The method includes the following steps: Primer preparation: S1. Mix the organic titanium crosslinking agent DuPont™ Tyzor® 371 with isopropanol until uniform to obtain primer component A, which is ready for use. S2. Mix the silica sol, 1% NaOH solution, pigment, filler, and dispersant evenly, grind to a fineness of less than 20 μm, test its pH value, and if it is less than 9.5, adjust it to 9.5-10 with 1% NaOH solution; add the hydroxyethyl cellulose aqueous solution, stir evenly to obtain a color paste, and set aside for use; S3. Mix the methyltrimethoxysilane, acetic acid, leveling agent, and deionized water evenly, then add the color paste and mix well to obtain primer component B. And, preparation of topcoat: S4. Mix the organic titanium crosslinking agent DuPont™ Tyzor® 371 with isopropanol until uniform to obtain topcoat component A, which is ready for use. S5. Mix the methyltrimethoxysilane, acetic acid, leveling agent, non-sticking agent, and deionized water evenly, then add silica sol and mix well to obtain the topcoat component B.

5. The method for preparing cold-sprayed ceramic coating according to claim 4, characterized in that, In steps S3 and S5, the mixing is carried out under the condition of rolling at 120-150 rpm for 6-8 hours.

6. A method for applying a cold-sprayed ceramic coating prepared according to claim 5, characterized in that, The method includes the following steps: A1. After mixing the primer components A and B evenly, spray them onto the substrate surface; A2. After the primer is applied, mix the topcoat components A and B evenly, and then spray the topcoat onto the primer surface using a wet-on-wet method. A3. Low temperature: 80-100℃ for 5-8 minutes; High temperature: 230-260℃ for 10-15 minutes to complete curing.

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