Silicon carbide whisker oriented reinforced wear resistant and friction reducing phosphate ceramic coating and method of making same

Abstract

The present application belongs to the technical field of ceramic coating, and particularly relates to a silicon carbide whisker directional reinforced wear-resistant and friction-reducing phosphate ceramic coating and a preparation method thereof. The coating material comprises the following components by mass fraction: 1-5 wt% of magnetic silicon carbide whisker, 2 wt% of curing agent, 50.5 wt% of phosphate binder, and 42.5-47.5 wt% of aggregate alumina. The present application adopts a hydrothermal synthesis method to prepare the magnetic silicon carbide whisker, and then mixes the alumina, zinc oxide and phosphate binder to obtain a coating material. Finally, the composite coating material is coated on the surface of a metal substrate, and the arrangement direction of the silicon carbide whisker is controlled by using the magnetic field auxiliary effect in the curing process, so as to obtain the silicon carbide whisker directional reinforced wear-resistant and friction-reducing phosphate ceramic coating. The coating has excellent wear-resistant and friction-reducing performance, can effectively protect the coating from damage, prolong the service life of the coating, and has a wide application prospect in the field of coating wear-resistant protection.

Description

Technical Field

[0001] This invention relates to the field of ceramic coating technology, and in particular to a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating and its preparation method. Background Technology

[0002] In an era of continuous technological and industrial development, the automotive, aerospace, and other manufacturing industries are constantly pursuing lighter and more portable products to save energy, frequently employing large quantities of lightweight metal materials such as titanium alloys and aluminum alloys in production. Compared to some other materials, lightweight metals typically have lower hardness, making them more susceptible to wear during friction. With prolonged use, this reduces the durability and lifespan of these metal components. Furthermore, due to the limited surface smoothness of lightweight metals, additional lubricants may be needed to reduce friction and wear, increasing the complexity of using and maintaining metal products. Therefore, improving the wear resistance and friction reduction properties of metallic materials has become a popular research direction.

[0003] Inorganic phosphate ceramic coatings, with their high mechanical strength, good thermal stability, and non-toxic and environmentally friendly properties, have been widely used to improve the high-temperature oxidation performance of light metals such as titanium alloys, demonstrating good economic efficiency and ease of application. However, limitations in the preparation process and methods of inorganic phosphate ceramic coatings result in defects such as poor toughness and insufficient wear and friction reduction properties, seriously affecting their widespread use in industrial fields. Therefore, developing a coating material with wear-resistant and friction-reducing properties has become a research hotspot.

[0004] Silicon carbide whiskers are ceramic materials with high-temperature stability and excellent wear resistance, significantly enhancing the wear and friction reduction properties of coatings. They are a crucial material widely used in metal coating technology. Silicon carbide whiskers possess excellent hardness and wear resistance, maintaining their superior mechanical properties even under high temperature and pressure conditions. They are not easily worn or deformed, allowing them to effectively protect coatings, enhance their protective effect, and extend their service life. Furthermore, silicon carbide whiskers exhibit good lubrication properties, forming a uniform lubricating layer on the coating surface, reducing the coefficient of friction between metals, thereby effectively reducing coating wear and friction. This improves the coating's wear resistance while also reducing metal material wear and maintenance costs.

[0005] Chinese patent application CN114410188A discloses an organic-inorganic nanocomposite coating material, its preparation method, and its application. The composite coating incorporates nano-silicon carbide whiskers, resulting in a material with excellent wear resistance and high toughness. Chinese patent application CN114412914A discloses a wear-resistant alloy hinge and its processing technology. This invention includes an alloy spring steel hinge coating. The coating materials include molybdenum disulfide, nickel powder, tungsten carbide, silicon carbide whiskers, silicon carbide, and additives. The addition of silicon carbide whiskers to the coating not only toughens the material but also effectively improves its wear resistance under different working environments, significantly enhancing the overall mechanical properties of the silicon carbide ceramic. Chinese patent application CN113214718A discloses a wear-resistant coating, its preparation method, and its application. This wear-resistant coating contains 50-70 parts of silicon carbide whiskers in its raw materials, greatly improving the coating's wear resistance. In summary, the addition of silicon carbide whisker materials can improve the wear resistance of the coating. However, further research is needed on how to modify silicon carbide whisker materials to improve their wear resistance and friction reduction properties while extending the service life of the coating and obtaining a more ideal wear-resistant coating. Summary of the Invention

[0006] To overcome the limitations of existing inorganic phosphate ceramic coating preparation processes and methods, which result in poor toughness and insufficient wear and friction reduction properties, this invention provides a silicon carbide whisker-reinforced wear-resistant and friction-reducing phosphate ceramic coating and its preparation method. This method introduces magnetic silicon carbide whiskers and orients them, which can more effectively improve the wear and friction reduction properties of the phosphate composite coating, while further enhancing its service life under high-temperature working environments, thereby achieving a long-term protective effect of the coating and improving the service life of metal materials.

[0007] A silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating is composed of the following raw materials in the following mass fraction ratios: 42.5-47.5 wt% ceramic aggregate, 2 wt% curing agent, 50.5 wt% phosphate binder, and 1-5 wt% reinforcing phase.

[0008] Furthermore, the magnetic silicon carbide whiskers in the coating are oriented parallel to the substrate surface.

[0009] Furthermore, the reinforcing phase is a magnetic silicon carbide whisker, which is prepared by sequentially coating silicon carbide whiskers with dopamine and iron oxide; the diameter of the silicon carbide whiskers is 0.1 μm to 0.6 μm. However, if the amount of magnetic silicon carbide whiskers added exceeds 5%, the coating is prone to agglomeration; therefore, its range is limited to 1–5 wt%.

[0010] Furthermore, the curing agent is zinc oxide; the binder is aluminum dihydrogen phosphate; and the ceramic aggregate is alumina.

[0011] This invention provides a method for preparing a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating, comprising the following steps:

[0012] Weigh out magnetic silicon carbide whiskers, curing agent, ceramic aggregate and phosphate binder. Ball mill and mix the magnetic silicon carbide whiskers, curing agent and ceramic aggregate, then mix and stir with phosphate binder until uniform. Coat the mixture onto a pretreated metal substrate and cure at room temperature for 8 hours in a weak magnetic field environment to orient the magnetic silicon carbide whiskers. Then perform step curing treatment to obtain a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating with a thickness of 0.20-0.25 mm.

[0013] Furthermore, the ball milling speed is 250 r·min. -1 The ball milling time is 1 hour, the mass ratio of balls to material is 1.2:1, and the balls are made of agate.

[0014] Furthermore, the magnetic field strength of the weak magnetic field environment is 0.5 to 1.0 T.

[0015] Furthermore, the gradient curing process is as follows: cure for 1 hour each at 50℃, 100℃, and 150℃, then cure for 2 hours each at 200℃ and 270℃, and then cool with the furnace.

[0016] Furthermore, the method for preparing the magnetic silicon carbide whiskers includes the following steps:

[0017] Step 1: Mix tris(hydroxymethyl)aminomethane with deionized water until the pH of the reaction solution reaches 8.5. Sonicate the mixture for 30 minutes. Then add silicon carbide whiskers at a mass ratio of (80-90):(10-20) and sonicate again for 30 minutes. Add dopamine hydrochloride at a mass ratio of (25-30):(70-75) and stir the mixture at room temperature for 8 hours. After the reaction, centrifuge the resulting mixture and wash it 5-6 times with deionized water. Finally, dry the mixture completely at 80-100℃ to obtain dopamine-modified silicon carbide whisker powder.

[0018] Step 2: Dissolve ferric chloride hexahydrate in ethylene glycol at a ratio of (1-2) g:(200-300) mL. Add dopamine-modified silicon carbide whisker powder and polyethylene glycol to the solution in an ultrasonic bath. Then, slowly add sodium acetate and stir vigorously at 60-80°C for 2-3 hours. Seal the mixture in a PTFE reactor and heat at 100°C for 2 hours. Increase the temperature to 160-200°C and continue heating for 15-20 hours. After cooling to room temperature, centrifuge the resulting mixture and wash it 5-6 times with deionized water. Finally, dry completely at 80-100°C to obtain magnetic silicon carbide whiskers.

[0019] Preferably, the weight percentages of the raw materials in step two are: ferric chloride hexahydrate 4-6 wt%, polyethylene glycol 18-22 wt%, dopamine-modified silicon carbide whiskers 4-6 wt%, and sodium acetate 66%-74 wt%.

[0020] Furthermore, the specific steps of the pretreatment are as follows: First, use coarse sandpaper to remove rust and oxides from the metal surface; then, use deionized water to preliminarily rinse away surface debris; then, use an ultrasonic cleaner to ultrasonically clean the surface with alcohol as the cleaning solution; finally, dry the surface.

[0021] The silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating prepared by the above method has applications in aerospace maintenance, ceramic material reinforcement, light metal surface protection, and improved friction materials.

[0022] The beneficial effects of this invention are as follows:

[0023] (1) In this invention, dopamine and iron oxide are sequentially coated on silicon carbide whiskers to obtain magnetic silicon carbide whiskers. Under the action of a magnetic field, the whiskers are aligned parallel to the substrate surface, while the strength of the silicon carbide whiskers is further enhanced, the bonding strength between the coating and the metal substrate is improved, the surface of the silicon carbide whiskers is effectively protected, and the service life of the coating is increased.

[0024] (2) The oriented silicon carbide whiskers can fully utilize their load-transfer function to form a robust protective layer within the material, improving the coating hardness and making the stress distribution more uniform, thus enhancing the load-bearing capacity of the composite material. Furthermore, pulling out the silicon carbide whiskers requires overcoming the interfacial bonding force with the coating, consuming a large amount of fracture energy. Simultaneously, the whisker pull-out blunts the crack tips, increasing the resistance to crack propagation and significantly improving the wear resistance of the coating.

[0025] (3) The silicon carbide whisker oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating of the present invention uses green, non-toxic, safe and environmentally friendly materials. The operation process is simple, greatly reducing processing energy consumption. It is easy to produce, promote and apply in practice. It has a favorable market prospect in the fields of reinforced ceramic materials, light metal protection and improved friction materials. Attached image description:

[0026] Figure 1 The microstructure images are of the coatings obtained in Example 2(b) and Comparative Example 3(a).

[0027] Figure 2 A schematic diagram illustrating the application of a magnetic field during the coating curing process;

[0028] Figure 3 The bar chart shows the room temperature friction coefficients of the coatings obtained in Examples 1-2 and Comparative Examples 1-5.

[0029] Figure 4 The bar chart shows the room temperature wear rate of the coatings obtained in Examples 1-2 and Comparative Examples 1-5.

[0030] Figure 5 The bar chart shows the high-temperature friction coefficients of the coatings obtained in Examples 1-2 and Comparative Examples 1-5.

[0031] Figure 6 The bar charts show the high-temperature wear rates of the coatings obtained in Examples 1-2 and Comparative Examples 1-5.

[0032] Figure 7 The images show the microstructure of the coatings obtained in Comparative Example 1 and Example 1 before and after high-temperature oxidation. (a) shows the microstructure of the coating in Comparative Example 1, (b) shows the microstructure of the coating in Comparative Example 1 after high-temperature oxidation, (c) shows the microstructure of the coating in Example 1, and (d) shows the microstructure of the coating in Example 1 after high-temperature oxidation. Detailed Implementation

[0033] To further illustrate the present invention, the following detailed description, in conjunction with the accompanying drawings and embodiments, describes a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating material, coating, preparation method, and application provided by the present invention. However, this description should not be construed as limiting the scope of protection of the present invention.

[0034] Room temperature tribological performance testing: Tribological tests were conducted using a Lanzhou Zhongke Kaihua Technology HT-1000 testing machine. The test conditions included a test duration of 1800 s, a load of 10 N, 4 mm diameter silicon nitride spheres as the test targets, and a testing machine frequency of 8.93 Hz. The main reference indicators were the coefficient of friction and wear rate of the ceramic coating. To ensure the accuracy of the experiment, each sample was repeated five times, and the average value was taken.

[0035] High-Temperature Friction and Wear Performance Testing: Friction and wear tests were conducted using a Lanzhou Zhongke Kaihua Technology HT-1000 testing machine. The test conditions included a test time of 600 seconds, a load of 10 N, 4 mm diameter silicon nitride spheres as the test grinding balls, a test temperature of 400℃, and a testing machine frequency of 8.93 Hz. The main reference indicators were the coefficient of friction and wear rate of the ceramic coating. To ensure the accuracy of the experiment, each sample was repeated five times, and the average value was taken.

[0036] High-temperature oxidation performance test: A muffle furnace (model SX2-5-12A) manufactured by Shaoxing Shangyu Daoxu Kexi Instrument Factory was used for high-temperature oxidation testing. The test conditions were: temperature 800℃, duration 800 min; after the test, the microstructure of the coating was observed using a TESCANMAGNA SEM electron microscope.

[0037] Example 1

[0038] (1) Mix 0.3025g of tris(hydroxymethyl)aminomethane with 250ml of deionized water and stir until homogeneous. Add hydrochloric acid to adjust the pH to 8.5. Add 1.5g of silicon carbide whisker powder (Nangong Bole Metal Materials Co., Ltd., model SiCw-1). Sonicate the resulting mixture for 30 minutes. Then add 0.6g of dopamine hydrochloride and stir at room temperature for 8 hours. After the reaction is complete, centrifuge the obtained powder and wash it with deionized water 5-6 times. Dry it completely at 80-100℃ to obtain dopamine-modified silicon carbide whiskers.

[0039] (2) Disperse 1.5g of ferric chloride hexahydrate into 200ml of ethylene glycol, then add 5g of polyethylene glycol and 1.5g of dopamine-modified silicon carbide whiskers, slowly add 18g of sodium acetate, sonicate the solution for 1 hour, stir at 60℃ in a water bath for 2 hours, put the resulting mixed solution into a polytetrafluoroethylene reactor, heat at 100℃ for 2 hours, then adjust to 180℃ and heat for 15 hours, cool to room temperature, centrifuge the resulting mixture, wash with deionized water 5-6 times, and dry completely at 80-100℃ to obtain magnetic silicon carbide whiskers;

[0040] (3) Weigh the raw materials according to the following mass ratio: 3wt% magnetic silicon carbide whisker material, 2wt% zinc oxide, 44.5wt% aluminum oxide, and 50.5wt% aluminum dihydrogen phosphate;

[0041] (4) The magnetic silicon carbide whiskers, zinc oxide, and alumina were mixed and ground using a ball mill. The ball milling speed was 250 r / min. -1 The total ball milling time is 1 hour, the ratio of balls to material is 1.2:1, and the balls are made of agate.

[0042] (5) Add aluminum dihydrogen phosphate binder to the ball-milled powder and mix it thoroughly and evenly by magnetic stirring for 1 hour.

[0043] (6) Roughening and cleaning pretreatment of the metal substrate surface. First, use coarse sandpaper to remove rust and oxides from the metal surface; then use deionized water to pre-rinse the surface debris; then use an ultrasonic cleaner to clean the surface with alcohol as the cleaning solution for 30 minutes; finally, use a hair dryer to dry the metal substrate surface.

[0044] (7) Apply the uniformly mixed slurry to the surface of the treated metal substrate by scraping.

[0045] (8) The coating is cured using the following process: first, it is cured at room temperature for 8 hours in a weak magnetic field environment with a magnetic field strength of 0.5 to 1.0 T; then, it is cured at 50℃, 100℃, and 150℃ for 1 hour each, and finally, it is heated at 200℃ and 270℃ for 2 hours each. After furnace cooling, a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating with a thickness of 0.20 to 0.25 mm is obtained.

[0046] Example 2

[0047] The difference between Example 2 and Example 1 is that step (3) is modified as follows: weigh the raw materials according to the following mass ratio: 5wt% magnetic silicon carbide whisker material, 2wt% zinc oxide, 50.5wt% aluminum dihydrogen phosphate, 42.5wt% aluminum oxide, and the rest are the same as in Example 1.

[0048] Comparative Example 1

[0049] (1) Weigh the raw materials according to the following mass ratio: 2 wt% zinc oxide, 50.5 wt% aluminum dihydrogen phosphate, and 47.5 wt% aluminum oxide.

[0050] (2) Zinc oxide and alumina were mixed and ground using a ball mill. The ball milling speed was 250 r / min. -1 The total ball milling time is 1 hour, the ratio of balls to material is 1.2:1, and agate balls are used.

[0051] (3) Add aluminum dihydrogen phosphate binder to the ball-milled powder and mix it thoroughly and evenly by magnetic stirring for 1 hour.

[0052] (4) Roughening and cleaning pretreatment of the metal substrate surface. First, use coarse sandpaper to remove rust and oxides from the metal surface; then use deionized water to rinse the surface debris; then use an ultrasonic cleaner to clean the surface with alcohol as the cleaning solution for 30 minutes; finally, use a hair dryer to dry the metal substrate surface.

[0053] (5) The uniformly mixed slurry is coated onto the surface of the treated metal substrate by scraping.

[0054] (6) The coating is cured by the following process: first, it is cured at room temperature for 8 hours, then cured at 50℃, 100℃ and 150℃ for 1 hour each, and finally heated at 200℃ and 270℃ for 2 hours each. After cooling in the furnace, the inorganic phosphate ceramic coating is obtained.

[0055] Comparative Example 2

[0056] The difference between Comparative Example 2 and Example 1 is that in step (8), "curing at room temperature for 8 hours in a weak magnetic field environment" is changed to "curing at room temperature for 8 hours". The rest is the same as in Example 1.

[0057] Comparative Example 3

[0058] The difference between Comparative Example 3 and Example 2 is that in step (8), "curing at room temperature for 8 hours in a weak magnetic field environment" is changed to "curing at room temperature for 8 hours". The rest is the same as in Example 2.

[0059] Comparative Example 4

[0060] The difference between Comparative Example 4 and Example 1 is that steps (1)-(2) are omitted, and step (3) is changed to: weighing raw materials according to the following mass ratio: 3wt% silicon carbide whiskers, 2wt% zinc oxide, 44.5wt% aluminum oxide, and 50.5wt% aluminum dihydrogen phosphate, and the rest is the same as in Example 1.

[0061] Comparative Example 5

[0062] The difference between Comparative Example 5 and Example 2 is that steps (1)-(2) are omitted, and step (3) is changed to: weighing raw materials according to the following mass ratio: 5wt% silicon carbide whiskers, 2wt% zinc oxide, 50.5wt% aluminum dihydrogen phosphate, and 42.5wt% aluminum oxide, and the rest is the same as in Example 2.

[0063] The wear resistance behavior of silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coatings was evaluated by room temperature and high temperature friction and wear tests. The test results are shown in Table 1.

[0064] Table 1 Performance index of coating samples from Examples 1-2 and Comparative Examples 1-5

[0065]

[0066] The room temperature friction coefficients of each coated sample are as follows: Figure 3 As shown, the wear rate at room temperature is as follows: Figure 4As shown in the figure, the addition of magnetic silicon carbide whiskers significantly reduces the coefficient of friction and wear rate of the coating, and the coefficient of friction decreases with increasing magnetic silicon carbide whisker content. Without magnetic field orientation, the coating with a magnetic silicon carbide whisker content of 5 wt% (Comparative Example 3) exhibits better wear resistance and friction reduction performance. Compared to the coating without magnetic silicon carbide whiskers (Comparative Example 1), the room temperature coefficient of friction is reduced by 38.4%, and the room temperature wear rate is reduced by 26.7%. However, when the magnetic silicon carbide whisker content exceeds 5%, the coating exhibits a more pronounced grainy texture, excessively high viscosity making it difficult to stir evenly, and hindering coating operations.

[0067] The oriented alignment of magnetic silicon carbide whiskers in the coating under the influence of a magnetic field can further reduce the coefficient of friction and wear rate of the material, with the best effect achieved when the content of magnetic silicon carbide whiskers is 5 wt%. Compared with the coating without magnetic silicon carbide whiskers (Comparative Example 1) and the coating with 5 wt% unoriented magnetic silicon carbide whiskers (Comparative Example 3), the coating containing 5 wt% oriented magnetic silicon carbide whiskers (Example 2) showed a 51.9% and 21.9% reduction in the coefficient of friction at room temperature, respectively, and a 63.1% and 49.6% reduction in the wear rate at room temperature, respectively. This is because the magnetic silicon carbide whiskers are more uniformly distributed after being oriented by the magnetic field, resulting in better load transfer under stress.

[0068] The coefficients of friction of each coating sample at high temperature are as follows: Figure 5 As shown, the wear rate is as follows Figure 6 As shown in the figure, the friction coefficient and wear rate of each coating sample are higher at high temperature than at room temperature. The coating containing oriented magnetic silicon carbide whiskers (Example 2) has better high temperature friction and wear resistance than the coating without silicon carbide whiskers (Comparative Example 1), the coating containing silicon carbide whiskers (Comparative Example 5), and the coating containing 5 wt% unoriented magnetic silicon carbide whiskers (Comparative Example 3).

[0069] High-temperature oxidation test results show that the magnetic silicon carbide whisker coating exhibits good high-temperature oxidation resistance after directional alignment. The magnetic silicon carbide whiskers in the coating can act as a good bridge and promote the reaction of the binder at high temperatures, thereby forming a relatively dense network structure that protects the coating from oxide erosion, improves the high-temperature stability of the coating, and exhibits better wear resistance and friction reduction properties, thus extending the service life of the coating and protecting the substrate from damage.

[0070] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating, characterized in that, The coating is composed of the following raw materials in the following mass fraction ratios: 42.5~47.5wt% ceramic aggregate, 2wt% curing agent, 50.5wt% phosphate binder, and 1~5wt% reinforcing phase, wherein the reinforcing phase is magnetic silicon carbide whiskers; In the coating, the magnetic silicon carbide whiskers are oriented parallel to the substrate surface; The magnetic silicon carbide whiskers are prepared by sequentially coating silicon carbide whiskers with dopamine and iron oxide. The diameter of the silicon carbide whiskers is 0.1µm to 0.6µm; the curing agent is zinc oxide; the phosphate binder is aluminum dihydrogen phosphate; and the ceramic aggregate is alumina.

2. A method for preparing a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating according to claim 1, characterized in that, The process includes the following steps: Weighing magnetic silicon carbide whiskers, curing agent, ceramic aggregate, and phosphate binder; ball milling and mixing the magnetic silicon carbide whiskers, curing agent, and ceramic aggregate; mixing and stirring the mixture with the phosphate binder until homogeneous; coating the mixture onto a pretreated metal substrate; curing at room temperature for 8 hours in a weak magnetic field environment; then curing at 50℃, 100℃, and 150℃ for 1 hour each; and finally curing at 200℃ and 270℃ for 2 hours each. The mixture is then cooled in the furnace to obtain a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating.

3. The method for preparing a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating according to claim 2, characterized in that, The ball milling rotation speed is 250 r·min -1 The ball milling total time is 1 hour, and the mass ratio of ball to material is 1.2:

1.

4. The method for preparing the silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating according to claim 2, characterized in that: The magnetic field strength of the weak magnetic field environment is 0.5~1.0T.

5. The method for preparing a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating according to claim 2, characterized in that, The thickness of the silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating is 0.20~0.25mm.

6. The method for preparing a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating according to claim 2, characterized in that, The specific steps for preparing the magnetic silicon carbide whiskers are as follows: Step 1: Mix tris(hydroxymethyl)aminomethane with deionized water evenly, add an appropriate amount of hydrochloric acid to adjust the pH to 8.5, and sonicate for 30 min; then add silicon carbide whiskers, with a mass ratio of silicon carbide whiskers to tris(hydroxymethyl)aminomethane of (80~90):(10~20), mix and sonicate for 30 min, then add dopamine hydrochloride, with a mass ratio of dopamine hydrochloride to silicon carbide whiskers of 25~30:(70~75), and stir the reaction at room temperature for 8 h; after the reaction is completed, centrifuge, wash and dry to obtain dopamine-modified silicon carbide whiskers; Step 2: Dissolve ferric chloride hexahydrate in ethylene glycol at a ratio of (1~2) g to (200~300) mL. Add dopamine-modified silicon carbide whiskers and polyethylene glycol, and mix thoroughly by ultrasonication. Slowly add sodium acetate and stir vigorously at 60~80℃ for 2~3 hours. Seal the resulting mixture in a polytetrafluoroethylene reactor and heat at 100℃ for 2 hours. Then raise the temperature to 160~200℃ and continue heating for 15~20 hours. Cool to room temperature, centrifuge, wash, and dry to obtain magnetic silicon carbide whiskers. The weight percentages of each raw material are: ferric chloride hexahydrate 4~6%, polyethylene glycol 18~22%, dopamine-modified silicon carbide whiskers 4~6%, and sodium acetate 66%~74%.

7. The method for preparing a silicon carbide whisker-oriented reinforced wear-resistant and friction-reducing phosphate ceramic coating according to claim 2, characterized in that, The specific steps of the pretreatment are as follows: First, use coarse sandpaper to remove rust and oxides from the metal surface; then, use deionized water to initially rinse away surface debris; then, use an ultrasonic cleaner to clean the surface with alcohol as the cleaning solution; finally, dry the surface.

Images