High-corrosion-resistance and wear-resistance tungsten-based hard alloy and preparation method thereof

Abstract

The application discloses a high-corrosion-resistance and wear-resistance tungsten-based hard alloy and a preparation method thereof, and relates to the technical field of hard alloys; the high-corrosion-resistance and wear-resistance tungsten-based hard alloy is composed of tungsten-based composite oxide@molybdenum disulfide-boron nitride hybrid nanofibers and graphene-coated core-shell composite powder; the tungsten-based composite oxide@molybdenum disulfide-boron nitride hybrid nanofibers and the graphene-coated core-shell composite powder are subjected to high-temperature sintering, the interface combination of the two is enhanced in a physical anchoring and chemical bonding mode, defects are reduced, external stress is effectively transmitted, the barrier protection effect is strengthened, the penetration of corrosion media is fully isolated, a multi-scale lubrication system is constructed, the wear of tungsten carbide and cobalt and the like is reduced, and therefore the bending strength, corrosion resistance and wear resistance are significantly enhanced, the service performance of the tungsten-based hard alloy is optimized, and the service cycle of the tungsten-based hard alloy is prolonged.

Description

Technical Field

[0001] This invention belongs to the field of cemented carbide technology, specifically referring to a high corrosion-resistant and wear-resistant tungsten-based cemented carbide and its preparation method. Background Technology

[0002] Cemented carbide is a composite material made by sintering high-hardness metal carbides (such as tungsten carbide and titanium carbide) with a metal binder phase (such as cobalt and nickel) through powder metallurgy. Among them, tungsten carbide-cobalt cemented carbide is the most typical and widely used cemented carbide system. Tungsten carbide-cobalt cemented carbide has high hardness, high heat resistance, high toughness, high strength and good wear resistance. It is widely used in the production of cutting tools, precision molds and wear-resistant parts, and has become an irreplaceable material in the fields of cutting tools, mining equipment and military equipment.

[0003] The existing technology currently has the following main problems: Tungsten carbide-cobalt cemented carbide, especially the cobalt binder phase, is susceptible to corrosion and wear, which leads to a decline in material performance and a shortened lifespan. Summary of the Invention

[0004] In view of the above situation and to overcome the defects of the prior art, the present invention proposes a high corrosion-resistant and wear-resistant tungsten-based cemented carbide, comprising the following components in parts by weight: 20-30 parts of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers, and 80-90 parts of graphene-coated core-shell composite powder.

[0005] The tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers are made from the following components in parts by weight: 4-6 parts copper-nickel bimetallic MOF nanoparticles, 10-20 parts ammonium metatungstate, 8-10 parts polyvinylpyrrolidone, 3-5 parts sodium molybdate dihydrate, 6-8 parts thiourea, 0.8-1 parts boron nitride, and 4-5 parts Dow Corning Z-6020 silane coupling agent.

[0006] The graphene-coated core-shell composite powder is a core-shell structure powder obtained by first ball milling and plasma activation treatment of tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder, and then growing a graphene coating layer on the surface in situ.

[0007] The preparation method of the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers specifically includes the following steps: (1) Dissolve 1.0-1.2g of copper nitrate trihydrate and 0.4-0.6g of nickel nitrate hexahydrate in 15mL of deionized water and stir for 0.5-1h to form solution I for later use. Then dissolve 0.8-1.0g of trimesic acid in 25mL of anhydrous ethanol and stir for 0.5-1h to form solution II for later use. Then mix solution I and solution II and add 0.2-0.4g of polyvinylpyrrolidone. Stir evenly and place in a reaction vessel at 110-120℃ for 10-12h of hydrothermal reaction. Wash the product with anhydrous ethanol 3-5 times and vacuum dry at 60℃. Copper ions, nickel ions and trimesic acid are combined through coordinate bonds to form a bimetallic three-dimensional porous framework structure. Its porous structure and high specific surface area help to uniformly disperse tungsten species in the subsequent process and avoid particle agglomeration during calcination to obtain copper-nickel bimetallic MOF nanoparticles. (2) Disperse the copper-nickel bimetallic MOF nanoparticles obtained in step (1) in 6 mL of N,N-dimethylformamide solvent, sonicate for 30-50 min, then add ammonium metatungstate and polyvinylpyrrolidone, stir for 20-30 min to obtain the precursor spinning solution. Use electrospinning technology, set the voltage to 10-18 kV, and the feed rate to 0.03-0.05 mm / s. Place the collected fibers in a crucible, dry them at 50-60℃ for 1-2 h, and then calcine them in air at 500-550℃ with a heating rate of 1℃ / min for 1- After 2 hours, the precursor spinning solution is stretched into fibers under a high-voltage electric field. After calcination, a continuous, uniform, and porous nanofiber network structure is formed. Among them, copper oxide and nickel oxide generated by the pyrolysis of copper-nickel bimetallic MOF nanoparticles react with some tungsten trioxide to form CuWO4 / NiWO4 composite oxide, which has high hardness and chemical inertness, enhancing wear resistance and corrosion resistance. At the same time, CuWO4 / NiWO4 composite oxide and unreacted tungsten trioxide together form the rigid structure of the fiber, which effectively resists deformation and loss during wear and corrosion, thus obtaining tungsten-based composite oxide nanofibers. (3) Dissolve sodium molybdate dihydrate and thiourea in 30 mL of deionized water, then add the tungsten-based composite oxide nanofibers described in step (2), ultrasonically disperse for 10-20 min, adjust the pH to 4.0, and then react at 180-200℃ for 10-12 h. Wash the product 3-5 times with 80% ethanol solution, vacuum dry at 60℃, and then anneal at 350-400℃ for 1-2 h in an atmosphere of 2% hydrogen and 98% argon. A molybdenum disulfide coating layer is generated on the surface of the tungsten-based composite oxide nanofibers through hydrothermal sulfidation reaction, giving the surface toughness and forming a combination of rigidity and flexibility. The fibrous structure involves the formation of Mo-OW covalent bonds on the surface of molybdenum disulfide and tungsten-based composite oxide nanofibers, where oxygen vacancies enhance interfacial bonding and reduce stress concentration. The layered structure of molybdenum disulfide allows for slippage under stress, absorbing some mechanical energy and preventing brittle fiber fracture, thus enhancing bending strength. The low interlaminar shear strength of molybdenum disulfide reduces the coefficient of friction and surface wear. Simultaneously, a protective film forms on the material surface during friction, preventing direct contact with the fiber core. Furthermore, molybdenum disulfide can form a passivation layer in humid environments, blocking the penetration of corrosive media, resulting in tungsten-based composite oxide@molybdenum disulfide nanofibers. (4) Disperse 0.08-0.1g of boron nitride in 20mL of 90% ethanol solution, add 0.4-0.5mL of Dow Corning Z-6020 silane coupling agent, and sonicate for 40-50min to obtain a boron nitride suspension for later use. Then, immerse the tungsten-based composite oxide@molybdenum disulfide nanofibers described in step (3) into the boron nitride suspension, stir at 50-60℃ for 1-2h, vacuum dry at 80℃, and finally anneal at 300-320℃ for 0.5-1h. The boron nitride is anchored to the surface of molybdenum disulfide by Dow Corning Z-6020 silane coupling agent, thus enhancing the tungsten-based composite oxide@molybdenum disulfide nanofibers. The oxide nanofibers form a coating and modification layer. The diamino functional groups form Si-OW / Mo covalent bonds and hydrogen bonds with oxygen vacancies and sulfur vacancies on the fiber surface, which significantly enhances the interfacial bonding strength, fills fiber surface defects, reduces stress concentration and improves bending strength. The lubricating properties of molybdenum disulfide and the hard properties of boron nitride work synergistically to protect the fiber core from wear. Furthermore, the dense barrier formed by molybdenum disulfide and boron nitride effectively reduces the penetration of corrosive media. Among them, the hydrophobicity and chemical inertness of boron nitride can block the contact between corrosive media and fiber matrix, resulting in tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers. Preferably, in step (2), the amount of ammonium metatungstate added is 1.0-2.0g, and the amount of polyvinylpyrrolidone added is 0.8-1.0g. The ammonium metatungstate is calcined and decomposed to generate tungsten trioxide as the main phase material, which provides a rigid skeleton for the fiber and resists deformation by external force. Polyvinylpyrrolidone, as a polymer template, forms a uniform precursor with ammonium metatungstate and copper-nickel bimetallic MOF nanoparticles, ensuring that the fiber is continuous and uniform during electrospinning. The thermal decomposition and pore-forming effect of polyvinylpyrrolidone improves the toughness of the fiber, relieves stress concentration, and thus enhances the bending strength. Preferably, in step (3), the amounts of sodium molybdate dihydrate and thiourea added are 0.3-0.5g and 0.6-0.8g, respectively. Sodium molybdate dihydrate and thiourea provide molybdenum source and sulfur source, respectively, which can form a molybdenum disulfide coating layer. Sufficient thiourea can reduce sulfur vacancies in molybdenum disulfide, prevent defects from becoming corrosion initiation points, and also enhance the interfacial bonding between molybdenum disulfide and fibers, thereby improving wear resistance. Preferably, in step (4), the brand name of Dow Corning Z-6020 silane coupling agent is OFS-6020. Dow Corning Z-6020 silane coupling agent contains a double amino functional group, which can form stronger hydrogen bonds and covalent bonds with molybdenum disulfide and boron nitride, reducing interface defects and thus reducing the risk of wear and shedding.

[0008] This invention also provides a method for preparing a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, specifically including the following steps: S1. Tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder are loaded into a ball mill jar in a mass ratio of 10:3:1-2, with a ball-to-powder ratio of 5:1. Stearic acid is then added at 0.8-1.0% of the total powder mass. The mixture is first ball-milled at 180-200 rpm for 8-10 hours, then the speed is adjusted to 280-310 rpm for intermittent ball milling for 1-2 hours. During intermittent ball milling, the mixture is milled for 30 minutes, paused for 10 minutes, and then dry-mixed at 300 rpm for 3-4 hours under a high-purity argon atmosphere. The resulting mixed powder is then... Hydrogen plasma treatment is performed at a power of 80-120W for 10-30 minutes. The plasma-treated mixed powder is then placed in a ceramic boat, pushed into a tube furnace, sealed, evacuated, and purged with nitrogen. This process is repeated three times to complete gas replacement. The temperature is then raised to 750-800℃ at a rate of 5℃ / min, and a mixed carbon source of methanol and ethanol is introduced. The furnace is held at this temperature for 30-35 minutes, then cooled to room temperature, and the product is removed. This process first synthesizes a composite phase of tungsten carbide, cobalt, and nano-cerium dioxide. The nano-defects on its surface, created by plasma etching, provide a suitable environment for graphene nucleation. The growth site is then coated with graphene sheets synthesized from a carbon source, forming a core-shell structure with an outer layer of wrinkles. The core-shell composite phase provides basic hardness, while the graphene shell prevents crack propagation through crack deflection and bridging effects. The graphene shell can also form a transfer film during friction, reducing the coefficient of friction and reducing direct wear by encapsulating the composite phase. The chemical inertness and dense structure of graphene also help to hinder the penetration of corrosive media. Therefore, its application in tungsten-based cemented carbides can significantly improve bending strength, wear resistance, and corrosion resistance. Cerium dioxide nanoparticles are used for pinning... In the tungsten carbide grain boundaries and cobalt binder phase, not only are semi-coherent interfaces formed, increasing the interfacial bonding energy and requiring additional energy for crack propagation, but grain growth at high temperatures is also inhibited, resulting in grain refinement and composite phase strengthening. Furthermore, cerium dioxide nanoparticles effectively fill the pores of the tungsten carbide-cobalt pair, blocking corrosion channels. Moreover, the oxygen vacancies in cerium dioxide promote carbon source decomposition, making the graphene coverage more uniform. Cerium dioxide nanoparticles can also prevent the graphene shell from slipping during sintering, improving the stability of the coating layer, thus obtaining graphene-coated core-shell composite powder. S2. The tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and the graphene-coated core-shell composite powder described in step S1 are mixed uniformly by wet ball milling. During ball milling, the material-to-ball ratio is 5:1, the rotation speed is 200-250 rpm, and the time is 3-4 hours. The mixture is then vacuum dried at 60℃. The mixture is placed in a mold and pressed into a green body under 300 MPa. The green body is then placed in a pyrophyllite mold and sintered under high temperature and high pressure using a six-sided press, with argon gas introduced for protection. The temperature is first raised to 800℃ for 1-2 minutes, then raised to 1100-1200℃. The sintering pressure is fixed at 3-5 GPa, and the holding time is 4-8 minutes. The sample is then removed, polished, and the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers are further mixed. The molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder form a physical anchoring effect through mechanical interlocking. Furthermore, the dangling bonds such as C=O and C-OH at the edges of graphene can react with tungsten carbide or cobalt to form WC or Co-C bonds, enhancing interfacial bonding. External stress is effectively transferred through the interface, avoiding local stress concentration and improving bending strength. At the same time, it further enhances the chemical inert barrier protection, effectively isolating corrosive media and enhancing corrosion resistance. Moreover, the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder synergistically construct a multi-scale lubrication system, reducing material wear and obtaining a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide. Preferably, in step S1, the volume ratio of methanol to ethanol in the mixed carbon source is 3-4:1. By adjusting the carbon source flow rate, 2-5 layers of graphene are generated, which is beneficial to interfacial bonding.

[0009] The beneficial effects achieved by this invention are as follows: This invention enhances the interfacial bonding between tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder through high-temperature sintering. This physical anchoring and chemical bonding reduces defects, effectively transferring external stress and strengthening the barrier protection, fully isolating the penetration of corrosive media. It also constructs a multi-scale lubrication system, reducing wear from substances such as tungsten carbide and cobalt. This significantly enhances bending strength, corrosion resistance, and wear resistance, optimizing the performance of tungsten-based cemented carbide and extending its service life. In a tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofiber, copper-nickel bimetallic MOF nanoparticles, ammonium metatungstate, and polyvinylpyrrolidone were used as precursor spinning solutions to first prepare tungsten-based composite oxide nanofibers. Then, a molybdenum disulfide coating layer was formed on the surface of the tungsten-based composite oxide nanofibers through a hydrothermal vulcanization reaction, imparting surface toughness and forming a fiber structure that combines rigidity and flexibility. Finally, boron nitride was anchored to the molybdenum disulfide surface using Dow Corning Z-6020 silane coupling agent. The diamino functional groups interact with the oxygen and sulfur vacancies on the fiber surface to form a hybrid structure. The graphene-coated core-shell composite powder forms Si-OW / Mo covalent and hydrogen bonds, enhancing interfacial bonding strength, filling fiber surface defects, reducing stress concentration and improving flexural strength. The lubricating properties of molybdenum disulfide and the hardening properties of boron nitride work synergistically to protect the fiber core from wear. Simultaneously, the dense barrier formed by molybdenum disulfide and boron nitride effectively reduces the penetration of corrosive media. In the graphene-coated core-shell composite powder, a composite phase of tungsten carbide, cobalt, and nano-cerium dioxide forms the core, with in-situ grown graphene sheets on its surface forming the shell, creating a wrinkled core-shell structure. The graphene shell provides basic hardness, and its effect of crack deflection and bridging prevents crack propagation. The graphene shell can also form a transfer film during friction, reducing the coefficient of friction, and encapsulates the composite phase to reduce direct wear. The chemical inertness and dense structure of graphene also help to hinder the penetration of corrosive media. This invention uses tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder to create a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, effectively enhancing bending strength, corrosion resistance, and wear resistance, and optimizing the material's performance. Attached Figure Description

[0010] Figure 1 This is a scanning electron microscope image of the bending fracture surface of the high corrosion and wear resistant tungsten-based cemented carbide prepared in Example 1 of the present invention; Figure 2 The graphs show the bending strength results of Examples 1-4 and Comparative Examples 1-3 of the present invention. Figure 3 The figures show the volume wear rate results for Examples 1-4 and Comparative Examples 1-3 of the present invention. Figure 4 The graph shows the mass loss rate results of Examples 1-4 and Comparative Examples 1-3 of the present invention. Detailed Implementation

[0011] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0012] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those familiar to those skilled in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to this invention. The preferred embodiments and materials described herein are for illustrative purposes only and do not limit the scope of this application.

[0013] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods; unless otherwise specified, the experimental materials used in the following embodiments are all purchased from commercial channels. Example

[0014] This embodiment proposes a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, comprising the following components in parts by weight: 30 parts of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers, and 90 parts of graphene-coated core-shell composite powder.

[0015] Tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers are made from the following components in parts by weight: 6 parts copper-nickel bimetallic MOF nanoparticles, 20 parts ammonium metatungstate, 10 parts polyvinylpyrrolidone, 5 parts sodium molybdate dihydrate, 8 parts thiourea, 1 part boron nitride, and 5 parts Dow Corning Z-6020 silane coupling agent.

[0016] Graphene-coated core-shell composite powder is a core-shell structure powder obtained by first ball milling and plasma activation treatment of tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder, and then growing a graphene coating layer on the surface in situ.

[0017] The preparation method of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers specifically includes the following steps: (1) Dissolve 1.2g of copper nitrate trihydrate and 0.6g of nickel nitrate hexahydrate in 15mL of deionized water and stir for 1h to form solution I for later use. Then dissolve 1.0g of trimesic acid in 25mL of anhydrous ethanol and stir for 1h to form solution II for later use. Then mix solution I and solution II and add 0.4g of polyvinylpyrrolidone. Stir evenly and place in a reaction vessel at 120℃ for 12h of hydrothermal reaction. Wash the product with anhydrous ethanol 5 times and vacuum dry at 60℃. Copper ions, nickel ions and trimesic acid are combined through coordinate bonds to form a bimetallic three-dimensional porous framework structure. Its porous structure and high specific surface area help to uniformly disperse tungsten species in the subsequent process and avoid particle agglomeration during calcination to obtain copper-nickel bimetallic MOF nanoparticles. (2) The copper-nickel bimetallic MOF nanoparticles described in step (1) were dispersed in 6 mL of N,N-dimethylformamide solvent and sonicated for 50 min. Then, ammonium metatungstate and polyvinylpyrrolidone were added. The amount of ammonium metatungstate added was 2.0 g and the amount of polyvinylpyrrolidone added was 1.0 g. The ammonium metatungstate was calcined and decomposed to generate tungsten trioxide as the main phase, which provided a rigid skeleton for the fiber and resisted deformation by external force. Polyvinylpyrrolidone, as a polymer template, formed a uniform precursor with ammonium metatungstate and copper-nickel bimetallic MOF nanoparticles, ensuring that the fiber was continuous and uniform during electrospinning. The thermal decomposition of polyvinylpyrrolidone created pores, which improved the toughness of the fiber and relieved stress concentration, thereby enhancing the bending strength. After stirring for 30 min, the precursor spinning solution was obtained. Electrospinning technology was used, and the electric current was set to... The collected fibers were placed in a crucible under a high voltage of 18kV and a propulsion rate of 0.05mm / s. They were first dried at 60℃ for 2 hours, and then calcined in air at 550℃ with a heating rate of 1℃ / min for 2 hours. The precursor spinning solution was stretched into fibers under a high voltage electric field. After calcination, a continuous, uniform, and porous nanofiber network structure was formed. The copper oxide and nickel oxide generated by the pyrolysis of copper-nickel bimetallic MOF nanoparticles reacted with some tungsten trioxide to form CuWO4 / NiWO4 composite oxide, which has high hardness and chemical inertness, enhancing wear resistance and corrosion resistance. At the same time, CuWO4 / NiWO4 composite oxide and unreacted tungsten trioxide together formed the rigid structure of the fiber, which effectively resisted deformation and loss during wear and corrosion. Tungsten-based composite oxide nanofibers were obtained. (3) Dissolve sodium molybdate dihydrate and thiourea in 30 mL of deionized water. The amounts of sodium molybdate dihydrate and thiourea added are 0.5 g and 0.8 g, respectively. Sodium molybdate dihydrate and thiourea provide molybdenum source and sulfur source, respectively, which can form a molybdenum disulfide coating layer. Sufficient thiourea can reduce sulfur vacancies in molybdenum disulfide, avoid defects becoming corrosion initiation points, and also enhance the interfacial bonding between molybdenum disulfide and fibers, improving wear resistance. Then add the tungsten-based composite oxide nanofibers described in step (2), ultrasonically disperse for 20 min, adjust the pH to 4.0, and then react at 200 °C for 12 h. The product is washed 5 times with 80% ethanol solution, vacuum dried at 60 °C, and then annealed at 400 °C for 2 h in an atmosphere of 2% hydrogen and 98% argon. Hydrothermal sulfidation generates a molybdenum disulfide coating on the surface of tungsten-based composite oxide nanofibers, imparting surface toughness and forming a fiber structure that combines rigidity and flexibility. Molybdenum disulfide forms Mo-OW covalent bonds with oxygen vacancies on the surface of tungsten-based composite oxide nanofibers, enhancing interfacial bonding and reducing stress concentration. The layered structure of molybdenum disulfide can slip under stress, absorbing some mechanical energy, preventing brittle fiber fracture, and enhancing bending strength. The low interlaminar shear strength of molybdenum disulfide can reduce the coefficient of friction and reduce surface wear. At the same time, a protective film is formed on the material surface during friction, preventing direct contact with the fiber core. Furthermore, molybdenum disulfide can form a passivation layer in humid environments, blocking the penetration of corrosive media, thus obtaining tungsten-based composite oxide@molybdenum disulfide nanofibers. (4) Disperse 0.1g of boron nitride in 20mL of 90% ethanol solution, add 0.5mL of Dow Corning Z-6020 silane coupling agent. The brand name of Dow Corning Z-6020 silane coupling agent is OFS-6020. Dow Corning Z-6020 silane coupling agent contains a diamino functional group, which can form stronger hydrogen bonds and covalent bonds with molybdenum disulfide and boron nitride, reduce interface defects, and thus reduce the risk of wear and shedding. Ultrasonic treatment for 50min is used to obtain boron nitride suspension. Then, the tungsten-based composite oxide@molybdenum disulfide nanofibers described in step (3) are immersed in the boron nitride suspension, stirred at 60℃ for 2h, vacuum dried at 80℃, and finally annealed at 320℃ for 1h to nitride. Boron is anchored to the surface of molybdenum disulfide using Dow Corning Z-6020 silane coupling agent, forming a coating layer on tungsten-based composite oxide nanofibers. The diamino functional groups form Si-OW / Mo covalent bonds and hydrogen bonds with oxygen and sulfur vacancies on the fiber surface, significantly enhancing interfacial bonding strength, filling fiber surface defects, reducing stress concentration and improving flexural strength. The lubricating properties of molybdenum disulfide and the hard properties of boron nitride work synergistically to protect the fiber core from wear. Furthermore, the dense barrier formed by molybdenum disulfide and boron nitride effectively reduces the penetration of corrosive media. The hydrophobicity and chemical inertness of boron nitride can block the contact between corrosive media and the fiber matrix, resulting in tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers.

[0018] This embodiment provides a method for preparing a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, specifically including the following steps: S1. Tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder are loaded into a ball mill jar in a mass ratio of 10:3:2 (ball-to-powder ratio 5:1). Stearic acid is then added at 1.0% of the total powder mass. The mixture is first ball-milled at 200 rpm for 10 hours, then the speed is adjusted to 310 rpm for intermittent ball milling for 2 hours. During intermittent ball milling, the milling is paused for 10 minutes after every 30 minutes of milling. Then, the mixture is dry-mixed at 300 rpm for 4 hours under a protective atmosphere of high-purity argon. The resulting mixed powder is then subjected to hydrogen plasma treatment at 120W for 30 minutes. The plasma-treated mixed powder was then placed in a ceramic boat, pushed into a tube furnace, sealed, evacuated, and purged with nitrogen. This process was repeated three times to complete the gas replacement. The temperature was then raised to 800°C at a rate of 5°C / min. A mixed carbon source of methanol and ethanol was introduced, with a volume ratio of methanol to ethanol of 4:1. By adjusting the carbon source flow rate, 2-5 layers of graphene were ensured to be formed, which is beneficial for interfacial bonding. The mixture was held at this temperature for 35 minutes, then cooled to room temperature, and the product was removed. This process first synthesizes a composite phase of tungsten carbide, cobalt, and nano-cerium dioxide, the surface of which is formed by nano-scale etching. Defects provide growth sites for graphene nucleation. Graphene sheets synthesized with a carbon source then coat the composite phase, forming a core-shell structure with outer wrinkles. The core-shell composite phase provides basic hardness, while the graphene shell prevents crack propagation through crack deflection and bridging effects. The graphene shell can also form a transfer film during friction, reducing the coefficient of friction and reducing direct wear by encapsulating the composite phase. The chemical inertness and dense structure of graphene also help to hinder the penetration of corrosive media. Therefore, its use in tungsten-based cemented carbides can significantly improve bending strength, wear resistance, and corrosion resistance. Among these, cerium dioxide sodium... The cerium dioxide nanoparticles, anchored within the tungsten carbide grain boundaries and cobalt binder phase, not only form a semi-coherent interface, increasing the interfacial bonding energy and requiring additional energy for crack propagation, but also inhibit grain growth at high temperatures, thus refining the grains and strengthening the composite phase. Furthermore, the cerium dioxide nanoparticles effectively fill the pores of the tungsten carbide-cobalt pair, blocking corrosion channels. Moreover, the oxygen vacancies in cerium dioxide promote the decomposition of the carbon source, resulting in a more uniform graphene coverage. The cerium dioxide nanoparticles can also prevent the graphene shell from slipping during sintering, improving the stability of the coating layer, thus yielding a graphene-coated core-shell composite powder. S2. The tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and the graphene-coated core-shell composite powder described in step S1 are mixed uniformly by wet ball milling. During ball milling, the material-to-ball ratio is 5:1, the rotation speed is 250 rpm, the time is 4 hours, and the mixture is vacuum dried at 60℃. The mixture is then placed in a mold and pressed into a green body at 300 MPa. The green body is placed in a pyrophyllite mold and sintered under high temperature and high pressure using a six-sided press, with argon gas introduced for protection. The temperature is first raised to 800℃ for 2 minutes, then raised to 1200℃, the sintering pressure is fixed at 5 GPa, and the holding time is 8 minutes. The sample is then removed, polished, and the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers are further processed. The nanofibers and graphene-coated core-shell composite powder form a physical anchoring effect through mechanical interlocking. Furthermore, the dangling bonds such as C=O and C-OH at the edges of the graphene can react with tungsten carbide or cobalt to form WC or Co-C bonds, enhancing interfacial bonding. External stress is effectively transferred through the interface, avoiding local stress concentration and improving bending strength. At the same time, it further enhances the chemical inert barrier protection, effectively isolating corrosive media and enhancing corrosion resistance. Moreover, the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder synergistically construct a multi-scale lubrication system, reducing material wear and obtaining a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide.

[0019] In this embodiment, the bending fracture surface of the prepared high corrosion-resistant and wear-resistant tungsten-based cemented carbide was observed using scanning electron microscopy to examine its microstructure. Figure 1 This is a 2000x magnified SEM image of the bending fracture surface of the highly corrosion-resistant and wear-resistant tungsten-based cemented carbide prepared in Example 1, as shown below. Figure 1 The high corrosion and wear resistant tungsten-based cemented carbide prepared in this embodiment exhibits a relatively regular shape and tight bonding in its bending fracture surface. Example

[0020] This embodiment proposes a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, comprising the following components in parts by weight: 20 parts of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers, and 80 parts of graphene-coated core-shell composite powder.

[0021] Tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers are made from the following components in parts by weight: 4 parts copper-nickel bimetallic MOF nanoparticles, 10 parts ammonium metatungstate, 8 parts polyvinylpyrrolidone, 3 parts sodium molybdate dihydrate, 6 parts thiourea, 0.8 parts boron nitride, and 4 parts Dow Corning Z-6020 silane coupling agent.

[0022] Graphene-coated core-shell composite powder is a core-shell structure powder obtained by first ball milling and plasma activation treatment of tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder, and then growing a graphene coating layer on the surface in situ.

[0023] The preparation method of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers specifically includes the following steps: (1) Dissolve 1.0g of copper nitrate trihydrate and 0.4g of nickel nitrate hexahydrate in 15mL of deionized water and stir for 0.5h to form solution I for later use. Then dissolve 0.8g of trimesic acid in 25mL of anhydrous ethanol and stir for 0.5h to form solution II for later use. Then mix solution I and solution II and add 0.2g of polyvinylpyrrolidone. Stir evenly and place in a reaction vessel at 110℃ for 10h of hydrothermal reaction. Wash the product three times with anhydrous ethanol and vacuum dry at 60℃. Copper ions, nickel ions and trimesic acid are combined through coordinate bonds to form a bimetallic three-dimensional porous framework structure. Its porous structure and high specific surface area help to uniformly disperse tungsten species in the subsequent process and avoid particle agglomeration during calcination to obtain copper-nickel bimetallic MOF nanoparticles. (2) The copper-nickel bimetallic MOF nanoparticles described in step (1) were dispersed in 6 mL of N,N-dimethylformamide solvent and sonicated for 30 min. Then, ammonium metatungstate and polyvinylpyrrolidone were added. The amount of ammonium metatungstate added was 1.0 g, and the amount of polyvinylpyrrolidone added was 0.8 g. The ammonium metatungstate was calcined and decomposed to generate tungsten trioxide as the main phase, which provided a rigid skeleton for the fiber and resisted deformation by external force. Polyvinylpyrrolidone, as a polymer template, formed a uniform precursor with ammonium metatungstate and copper-nickel bimetallic MOF nanoparticles, ensuring that the fiber was continuous and uniform during electrospinning. The thermal decomposition of polyvinylpyrrolidone created pores, which improved the toughness of the fiber and relieved stress concentration, thereby enhancing the bending strength. After stirring for 20 min, the precursor spinning solution was obtained. Electrospinning technology was used, and the electric current was set to... The collected fibers were placed in a crucible under a high voltage of 10 kV and a propulsion rate of 0.03 mm / s. They were first dried at 50 °C for 1 h, and then calcined in air at 500 °C with a heating rate of 1 °C / min for 1 h. The precursor spinning solution was stretched into fibers under a high voltage electric field. After calcination, a continuous, uniform, and porous nanofiber network structure was formed. The copper oxide and nickel oxide generated by the pyrolysis of copper-nickel bimetallic MOF nanoparticles reacted with some tungsten trioxide to form CuWO4 / NiWO4 composite oxide, which has high hardness and chemical inertness, enhancing wear resistance and corrosion resistance. At the same time, CuWO4 / NiWO4 composite oxide and unreacted tungsten trioxide together formed the rigid structure of the fiber, which effectively resisted deformation and loss during wear and corrosion, thus obtaining tungsten-based composite oxide nanofibers. (3) Dissolve sodium molybdate dihydrate and thiourea in 30 mL of deionized water. The amounts of sodium molybdate dihydrate and thiourea added are 0.3 g and 0.6 g, respectively. Sodium molybdate dihydrate and thiourea provide molybdenum source and sulfur source, respectively, which can form a molybdenum disulfide coating layer. Sufficient thiourea can reduce sulfur vacancies in molybdenum disulfide, avoid defects becoming corrosion initiation points, and also enhance the interfacial bonding between molybdenum disulfide and fibers, improving wear resistance. Then add the tungsten-based composite oxide nanofibers described in step (2), ultrasonically disperse for 10 min, adjust the pH to 4.0, and then react at 180 °C for 10 h. The product is washed three times with 80% ethanol solution, vacuum dried at 60 °C, and then annealed at 350 °C for 1 h in an atmosphere of 2% hydrogen and 98% argon. Hydrothermal sulfidation generates a molybdenum disulfide coating on the surface of tungsten-based composite oxide nanofibers, imparting surface toughness and forming a fiber structure that combines rigidity and flexibility. Molybdenum disulfide forms Mo-OW covalent bonds with oxygen vacancies on the surface of tungsten-based composite oxide nanofibers, enhancing interfacial bonding and reducing stress concentration. The layered structure of molybdenum disulfide can slip under stress, absorbing some mechanical energy, preventing brittle fiber fracture, and enhancing bending strength. The low interlaminar shear strength of molybdenum disulfide can reduce the coefficient of friction and reduce surface wear. At the same time, a protective film is formed on the material surface during friction, preventing direct contact with the fiber core. Furthermore, molybdenum disulfide can form a passivation layer in humid environments, blocking the penetration of corrosive media, thus obtaining tungsten-based composite oxide@molybdenum disulfide nanofibers. (4) Disperse 0.08g of boron nitride in 20mL of 90% ethanol solution, add 0.4mL of Dow Corning Z-6020 silane coupling agent. The brand name of Dow Corning Z-6020 silane coupling agent is OFS-6020. Dow Corning Z-6020 silane coupling agent contains diamino functional groups, which can form stronger hydrogen bonds and covalent bonds with molybdenum disulfide and boron nitride, reduce interface defects, and thus reduce the risk of wear and shedding. Ultrasonic treatment for 40min is used to obtain boron nitride suspension. Then, the tungsten-based composite oxide@molybdenum disulfide nanofibers described in step (3) are immersed in the boron nitride suspension, stirred at 50℃ for 1h, vacuum dried at 80℃, and finally annealed at 300℃ for 0.5h. Boron nitride is anchored to the surface of molybdenum disulfide using Dow Corning Z-6020 silane coupling agent, forming a coating layer on tungsten-based composite oxide nanofibers. The diamino functional groups form Si-OW / Mo covalent bonds and hydrogen bonds with oxygen and sulfur vacancies on the fiber surface, significantly enhancing interfacial bonding strength, filling fiber surface defects, reducing stress concentration and improving flexural strength. The lubricating properties of molybdenum disulfide and the hard properties of boron nitride work synergistically to protect the fiber core from wear. Furthermore, the dense barrier formed by molybdenum disulfide and boron nitride effectively reduces the penetration of corrosive media. The hydrophobicity and chemical inertness of boron nitride can block the contact between corrosive media and the fiber matrix, resulting in tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers.

[0024] This embodiment provides a method for preparing a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, specifically including the following steps: S1. Tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder are loaded into a ball mill jar in a mass ratio of 10:3:1 (ball-to-powder ratio 5:1). Stearic acid is then added at 0.8% of the total powder mass. The mixture is first ball-milled at 180 rpm for 8 hours, then the speed is adjusted to 280 rpm for intermittent ball milling for 1 hour. During intermittent ball milling, the milling is paused for 10 minutes after a 30-minute pause. Then, the mixture is dry-mixed at 300 rpm for 3 hours under a high-purity argon atmosphere. The resulting mixed powder is then subjected to hydrogen plasma treatment at 80W for 10 minutes. Finally, the... The plasma-treated mixed powder was placed in a ceramic boat, pushed into a tube furnace, sealed, evacuated, and purged with nitrogen. This process was repeated three times to complete the gas replacement. The temperature was then raised to 750°C at a rate of 5°C / min. A mixed carbon source of methanol and ethanol (volume ratio of methanol to ethanol:1) was introduced. By adjusting the carbon source flow rate, 2-5 layers of graphene were ensured to be formed, which is beneficial for interfacial bonding. The mixture was held at this temperature for 30 minutes, then cooled to room temperature, and the product was removed. This process first synthesizes a composite phase of tungsten carbide, cobalt, and nano-cerium dioxide, the surface of which has nano-defects due to plasma etching. The pit provides growth sites for graphene nucleation. Graphene sheets synthesized with a carbon source then coat the composite phase, forming a core-shell structure with outer wrinkles. The core-shell composite phase provides basic hardness, while the graphene shell prevents crack propagation through crack deflection and bridging effects. The graphene shell can also form a transfer film during friction, reducing the coefficient of friction and reducing direct wear by encapsulating the composite phase. The chemical inertness and dense structure of graphene also help to hinder the penetration of corrosive media. Therefore, its use in tungsten-based cemented carbides can significantly improve bending strength, wear resistance, and corrosion resistance. Among these, cerium dioxide sodium... The cerium dioxide nanoparticles, anchored within the tungsten carbide grain boundaries and cobalt binder phase, not only form a semi-coherent interface, increasing the interfacial bonding energy and requiring additional energy for crack propagation, but also inhibit grain growth at high temperatures, thus refining the grains and strengthening the composite phase. Furthermore, the cerium dioxide nanoparticles effectively fill the pores of the tungsten carbide-cobalt pair, blocking corrosion channels. Moreover, the oxygen vacancies in cerium dioxide promote the decomposition of the carbon source, resulting in a more uniform graphene coverage. The cerium dioxide nanoparticles can also prevent the graphene shell from slipping during sintering, improving the stability of the coating layer, thus yielding a graphene-coated core-shell composite powder. S2. The tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and the graphene-coated core-shell composite powder described in step S1 are mixed uniformly by wet ball milling. During ball milling, the material-to-ball ratio is 5:1, the rotation speed is 200 rpm, the time is 3 hours, and the mixture is vacuum dried at 60℃. The mixture is then placed in a mold and pressed into a green body under 300 MPa. The green body is placed in a pyrophyllite mold and sintered under high temperature and high pressure using a six-sided press, with argon gas introduced for protection. The temperature is first raised to 800℃ for 1 minute, then raised to 1100℃, the sintering pressure is fixed at 3 GPa, and the holding time is 4 minutes. The sample is then removed, polished, and the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers are further processed. The nanofibers and graphene-coated core-shell composite powder form a physical anchoring effect through mechanical interlocking. Furthermore, the dangling bonds such as C=O and C-OH at the edges of the graphene can react with tungsten carbide or cobalt to form WC or Co-C bonds, enhancing interfacial bonding. External stress is effectively transferred through the interface, avoiding local stress concentration and improving bending strength. At the same time, it further enhances the chemical inert barrier protection, effectively isolating corrosive media and enhancing corrosion resistance. Moreover, the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder synergistically construct a multi-scale lubrication system, reducing material wear and obtaining a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide. Example

[0025] This embodiment proposes a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, comprising the following components in parts by weight: 25 parts of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers, and 85 parts of graphene-coated core-shell composite powder.

[0026] Tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers are made from the following components in parts by weight: 5 parts copper-nickel bimetallic MOF nanoparticles, 15 parts ammonium metatungstate, 9 parts polyvinylpyrrolidone, 4 parts sodium molybdate dihydrate, 7 parts thiourea, 0.9 parts boron nitride, and 4.5 parts Dow Corning Z-6020 silane coupling agent.

[0027] Graphene-coated core-shell composite powder is a core-shell structure powder obtained by first ball milling and plasma activation treatment of tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder, and then growing a graphene coating layer on the surface in situ.

[0028] The preparation method of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers specifically includes the following steps: (1) Dissolve 1.1g of copper nitrate trihydrate and 0.5g of nickel nitrate hexahydrate in 15mL of deionized water and stir for 0.75h to form solution I for later use. Then dissolve 0.9g of trimesic acid in 25mL of anhydrous ethanol and stir for 0.75h to form solution II for later use. Then mix solution I and solution II and add 0.3g of polyvinylpyrrolidone. Stir evenly and place in a reaction vessel at 115℃ for 11h of hydrothermal reaction. Wash the product with anhydrous ethanol 4 times and vacuum dry at 60℃. Copper ions, nickel ions and trimesic acid are combined through coordinate bonds to form a bimetallic three-dimensional porous framework structure. Its porous structure and high specific surface area help to uniformly disperse tungsten species in the subsequent process and avoid particle agglomeration during calcination to obtain copper-nickel bimetallic MOF nanoparticles. (2) The copper-nickel bimetallic MOF nanoparticles described in step (1) were dispersed in 6 mL of N,N-dimethylformamide solvent and sonicated for 40 min. Then, ammonium metatungstate and polyvinylpyrrolidone were added. The amount of ammonium metatungstate added was 1.5 g and the amount of polyvinylpyrrolidone added was 0.9 g. The ammonium metatungstate was calcined and decomposed to generate tungsten trioxide as the main phase, which provided a rigid skeleton for the fiber and resisted deformation by external force. Polyvinylpyrrolidone, as a polymer template, formed a uniform precursor with ammonium metatungstate and copper-nickel bimetallic MOF nanoparticles, ensuring that the fiber was continuous and uniform during electrospinning. The thermal decomposition of polyvinylpyrrolidone created pores, which improved the toughness of the fiber and relieved stress concentration, thereby enhancing the bending strength. After stirring for 25 min, the precursor spinning solution was obtained. Electrospinning technology was used, and the voltage was set to 1. At 4kV and a propulsion rate of 0.04mm / s, the collected fibers were placed in a crucible and dried at 55℃ for 1.5h. Then, they were calcined in air at 525℃ with a heating rate of 1℃ / min for 1.5h. The precursor spinning solution was stretched into fibers under a high-voltage electric field. After calcination, a continuous, uniform, and porous nanofiber network structure was formed. Among them, copper oxide and nickel oxide generated by the pyrolysis of copper-nickel bimetallic MOF nanoparticles reacted with some tungsten trioxide to form CuWO4 / NiWO4 composite oxide, which has high hardness and chemical inertness, enhancing wear resistance and corrosion resistance. At the same time, CuWO4 / NiWO4 composite oxide and unreacted tungsten trioxide together formed the rigid structure of the fiber, which effectively resisted deformation and loss during wear and corrosion, thus obtaining tungsten-based composite oxide nanofibers. (3) Dissolve sodium molybdate dihydrate and thiourea in 30 mL of deionized water. The amount of sodium molybdate dihydrate and thiourea added is 0.4 g and 0.7 g, respectively. Sodium molybdate dihydrate and thiourea provide molybdenum source and sulfur source, respectively, which can form a molybdenum disulfide coating layer. Sufficient thiourea can reduce sulfur vacancies in molybdenum disulfide, avoid defects becoming corrosion initiation points, and also enhance the interfacial bonding between molybdenum disulfide and fibers, improving wear resistance. Then add the tungsten-based composite oxide nanofibers described in step (2), ultrasonically disperse for 15 min, adjust the pH to 4.0, and then react at 190 °C for 11 h. The product is washed 4 times with 80% ethanol solution, vacuum dried at 60 °C, and then annealed at 375 °C for 1.5 h in an atmosphere of 2% hydrogen and 98% argon. A hydrothermal sulfidation reaction generates a molybdenum disulfide coating layer on the surface of tungsten-based composite oxide nanofibers, imparting surface toughness and forming a fiber structure that combines rigidity and flexibility. Molybdenum disulfide forms Mo-OW covalent bonds with oxygen vacancies on the surface of tungsten-based composite oxide nanofibers, enhancing interfacial bonding and reducing stress concentration. The layered structure of molybdenum disulfide can slip under stress, absorbing some mechanical energy, preventing brittle fiber fracture, and enhancing bending strength. The low interlaminar shear strength of molybdenum disulfide can reduce the coefficient of friction and reduce surface wear. At the same time, a protective film is formed on the material surface during friction, preventing direct contact with the fiber core. Furthermore, molybdenum disulfide can form a passivation layer in a humid environment, blocking the penetration of corrosive media, thus obtaining tungsten-based composite oxide@molybdenum disulfide nanofibers. (4) Disperse 0.09 g of boron nitride in 20 mL of 90% ethanol solution, add 0.45 mL of Dow Corning Z-6020 silane coupling agent (OFS-6020), which contains diamino functional groups and can form stronger hydrogen bonds and covalent bonds with molybdenum disulfide and boron nitride, reducing interface defects and thus reducing the risk of wear and detachment. Sonicate for 45 min to obtain a boron nitride suspension for later use. Then, immerse the tungsten-based composite oxide@molybdenum disulfide nanofibers described in step (3) into the boron nitride suspension, stir at 55°C for 1.5 h, vacuum dry at 80°C, and finally anneal at 310°C for 0.75 h. Boron nitride is anchored to the surface of molybdenum disulfide using Dow Corning Z-6020 silane coupling agent, forming a coating modification layer on the tungsten-based composite oxide nanofibers. The diamino functional groups form Si-OW / Mo covalent bonds and hydrogen bonds with oxygen and sulfur vacancies on the fiber surface, significantly enhancing the interfacial bonding strength, filling fiber surface defects, reducing stress concentration and improving bending strength. The lubricating properties of molybdenum disulfide and the hard properties of boron nitride work synergistically to protect the fiber core from wear. Furthermore, the dense barrier formed by molybdenum disulfide and boron nitride effectively reduces the penetration of corrosive media. Among them, the hydrophobicity and chemical inertness of boron nitride can block the contact between corrosive media and the fiber matrix, resulting in tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers.

[0029] This embodiment provides a method for preparing a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, specifically including the following steps: S1. Tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder are loaded into a ball mill jar in a mass ratio of 10:3:1.5 (ball-to-powder ratio 5:1). Stearic acid is then added at 0.9% of the total powder mass. The mixture is first ball-milled at 190 rpm for 9 hours, then the speed is adjusted to 295 rpm for intermittent ball milling for 1.5 hours. During intermittent ball milling, the milling is paused for 10 minutes after every 30 minutes of milling. Then, the mixture is dry-mixed at 300 rpm for 3.5 hours under a protective atmosphere of high-purity argon. The resulting mixed powder is then subjected to hydrogen plasma treatment at 100W for 20 minutes. Finally, the plasma-treated mixed powder was placed in a ceramic boat, pushed into a tube furnace, sealed, evacuated, and purged with nitrogen. This process was repeated three times to complete the gas replacement. The temperature was then raised to 775°C at a rate of 5°C / min. A mixed carbon source of methanol and ethanol was introduced, with a volume ratio of methanol to ethanol of 3.5:1. By adjusting the carbon source flow rate, 2-5 layers of graphene were ensured to be formed, which is beneficial for interfacial bonding. The temperature was maintained for 32.5 min, then cooled to room temperature, and the product was removed. This process first synthesizes a composite phase of tungsten carbide, cobalt, and nano-cerium dioxide, the surface of which is preserved due to plasma etching. The nanodefects provide growth sites for graphene nucleation. Graphene sheets synthesized with a carbon source then coat the composite phase, forming a core-shell structure with outer wrinkles. The core-shell composite phase provides basic hardness, while the graphene shell prevents crack propagation through crack deflection and bridging effects. The graphene shell can also form a transfer film during friction, reducing the coefficient of friction and reducing direct wear by encapsulating the composite phase. The chemical inertness and dense structure of graphene also help to hinder the penetration of corrosive media. Therefore, its use in tungsten-based cemented carbides can significantly improve bending strength, wear resistance, and corrosion resistance. Among these, carbon dioxide... Cerium nanoparticles are anchored in the tungsten carbide grain boundaries and cobalt binder phase, forming a semi-coherent interface, increasing the interfacial bonding energy, and requiring additional energy for crack propagation. They also inhibit grain growth at high temperatures, thus refining the grains and strengthening the composite phase. Furthermore, cerium dioxide nanoparticles effectively fill the pores of the tungsten carbide-cobalt pair, blocking corrosion channels. In addition, the oxygen vacancies in cerium dioxide promote the decomposition of the carbon source, making the graphene coverage more uniform. Cerium dioxide nanoparticles can also prevent the graphene shell from slipping during sintering, improving the stability of the coating layer, resulting in graphene-coated core-shell composite powder. S2. The tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and the graphene-coated core-shell composite powder described in step S1 are mixed uniformly by wet ball milling. During ball milling, the material-to-ball ratio is 5:1, the rotation speed is 225 rpm, and the time is 3.5 h. After vacuum drying at 60℃, the mixture is placed in a mold and pressed into a green body under 300 MPa. The green body is then placed in a pyrophyllite mold and sintered under high temperature and high pressure using a six-sided press, with argon gas introduced for protection. The temperature is first raised to 800℃ for 1.5 min, then raised to 1150℃, with the sintering pressure fixed at 4 GPa and the holding time at 6 min. The sample is then removed, polished, and the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers are mixed uniformly by wet ball milling. The tungsten-based composite nanofibers and graphene-coated core-shell composite powder form a physical anchoring effect through mechanical interlocking. Furthermore, the dangling bonds such as C=O and C-OH at the edges of graphene can react with tungsten carbide or cobalt to form WC or Co-C bonds, enhancing interfacial bonding. External stress is effectively transferred through the interface, avoiding local stress concentration and improving bending strength. At the same time, it further enhances the chemical inert barrier protection, fully isolating corrosive media and enhancing corrosion resistance. Moreover, the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder synergistically construct a multi-scale lubrication system, reducing material wear and obtaining a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide. Example

[0030] This embodiment proposes a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, comprising the following components in parts by weight: 30 parts of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers, and 80 parts of graphene-coated core-shell composite powder.

[0031] Tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers are made from the following components in parts by weight: 6 parts copper-nickel bimetallic MOF nanoparticles, 20 parts ammonium metatungstate, 10 parts polyvinylpyrrolidone, 3 parts sodium molybdate dihydrate, 6 parts thiourea, 0.8 parts boron nitride, and 4 parts Dow Corning Z-6020 silane coupling agent.

[0032] Graphene-coated core-shell composite powder is a core-shell structure powder obtained by first ball milling and plasma activation treatment of tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder, and then growing a graphene coating layer on the surface in situ.

[0033] The preparation method of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers specifically includes the following steps: (1) Dissolve 1.2g of copper nitrate trihydrate and 0.6g of nickel nitrate hexahydrate in 15mL of deionized water and stir for 0.5h to form solution I for later use. Then dissolve 1.0g of trimesic acid in 25mL of anhydrous ethanol and stir for 0.5h to form solution II for later use. Then mix solution I and solution II and add 0.4g of polyvinylpyrrolidone. Stir evenly and place in a reaction vessel at 120℃ for 10h of hydrothermal reaction. Wash the product with anhydrous ethanol 5 times and vacuum dry at 60℃. Copper ions, nickel ions and trimesic acid are combined through coordinate bonds to form a bimetallic three-dimensional porous framework structure. Its porous structure and high specific surface area help to uniformly disperse tungsten species in the subsequent process and avoid particle agglomeration during calcination to obtain copper-nickel bimetallic MOF nanoparticles. (2) The copper-nickel bimetallic MOF nanoparticles described in step (1) were dispersed in 6 mL of N,N-dimethylformamide solvent and sonicated for 30 min. Then, ammonium metatungstate and polyvinylpyrrolidone were added. The amount of ammonium metatungstate added was 2.0 g, and the amount of polyvinylpyrrolidone added was 1.0 g. The ammonium metatungstate was calcined and decomposed to generate tungsten trioxide as the main phase, which provided a rigid skeleton for the fiber and resisted deformation by external force. Polyvinylpyrrolidone, as a polymer template, formed a uniform precursor with ammonium metatungstate and copper-nickel bimetallic MOF nanoparticles, ensuring that the fiber was continuous and uniform during electrospinning. The thermal decomposition of polyvinylpyrrolidone created pores, which improved the toughness of the fiber and relieved stress concentration, thereby enhancing the bending strength. After stirring for 20 min, the precursor spinning solution was obtained. Electrospinning technology was used, and the electric current was set to... The collected fibers were placed in a crucible under a high voltage of 18kV and a propulsion rate of 0.05mm / s. They were first dried at 60℃ for 1h, and then calcined in air at 550℃ with a heating rate of 1℃ / min for 1h. The precursor spinning solution was stretched into fibers under a high voltage electric field. After calcination, a continuous, uniform, and porous nanofiber network structure was formed. The copper oxide and nickel oxide generated by the pyrolysis of copper-nickel bimetallic MOF nanoparticles reacted with some tungsten trioxide to form CuWO4 / NiWO4 composite oxide, which has high hardness and chemical inertness, enhancing wear resistance and corrosion resistance. At the same time, CuWO4 / NiWO4 composite oxide and unreacted tungsten trioxide together formed the rigid structure of the fiber, which effectively resisted deformation and loss during wear and corrosion. Tungsten-based composite oxide nanofibers were obtained. (3) Dissolve sodium molybdate dihydrate and thiourea in 30 mL of deionized water. The amounts of sodium molybdate dihydrate and thiourea added are 0.3 g and 0.6 g, respectively. Sodium molybdate dihydrate and thiourea provide molybdenum source and sulfur source, respectively, which can form a molybdenum disulfide coating layer. Sufficient thiourea can reduce sulfur vacancies in molybdenum disulfide, avoid defects becoming corrosion initiation points, and also enhance the interfacial bonding between molybdenum disulfide and fibers, improving wear resistance. Then add the tungsten-based composite oxide nanofibers described in step (2), ultrasonically disperse for 10 min, adjust the pH to 4.0, and then react at 200 °C for 10 h. The product is washed 5 times with 80% ethanol solution, vacuum dried at 60 °C, and then annealed at 400 °C for 1 h in an atmosphere of 2% hydrogen and 98% argon. Hydrothermal sulfidation generates a molybdenum disulfide coating on the surface of tungsten-based composite oxide nanofibers, imparting surface toughness and forming a fiber structure that combines rigidity and flexibility. Molybdenum disulfide forms Mo-OW covalent bonds with oxygen vacancies on the surface of tungsten-based composite oxide nanofibers, enhancing interfacial bonding and reducing stress concentration. The layered structure of molybdenum disulfide can slip under stress, absorbing some mechanical energy, preventing brittle fiber fracture, and enhancing bending strength. The low interlaminar shear strength of molybdenum disulfide can reduce the coefficient of friction and reduce surface wear. At the same time, a protective film is formed on the material surface during friction, preventing direct contact with the fiber core. Furthermore, molybdenum disulfide can form a passivation layer in humid environments, blocking the penetration of corrosive media, thus obtaining tungsten-based composite oxide@molybdenum disulfide nanofibers. (4) Disperse 0.08g of boron nitride in 20mL of 90% ethanol solution, add 0.4mL of Dow Corning Z-6020 silane coupling agent. The brand name of Dow Corning Z-6020 silane coupling agent is OFS-6020. Dow Corning Z-6020 silane coupling agent contains diamino functional groups, which can form stronger hydrogen bonds and covalent bonds with molybdenum disulfide and boron nitride, reduce interface defects, and thus reduce the risk of wear and shedding. Ultrasonic treatment for 40min is used to obtain boron nitride suspension. Then, the tungsten-based composite oxide@molybdenum disulfide nanofibers described in step (3) are immersed in the boron nitride suspension, stirred at 60℃ for 1h, vacuum dried at 80℃, and finally annealed at 320℃ for 0.5h. Boron nitride is anchored to the surface of molybdenum disulfide using Dow Corning Z-6020 silane coupling agent, forming a coating layer on tungsten-based composite oxide nanofibers. The diamino functional groups form Si-OW / Mo covalent bonds and hydrogen bonds with oxygen and sulfur vacancies on the fiber surface, significantly enhancing interfacial bonding strength, filling fiber surface defects, reducing stress concentration and improving flexural strength. The lubricating properties of molybdenum disulfide and the hard properties of boron nitride work synergistically to protect the fiber core from wear. Furthermore, the dense barrier formed by molybdenum disulfide and boron nitride effectively reduces the penetration of corrosive media. The hydrophobicity and chemical inertness of boron nitride can block the contact between corrosive media and the fiber matrix, resulting in tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers.

[0034] This embodiment provides a method for preparing a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, specifically including the following steps: S1. Tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder are loaded into a ball mill jar in a mass ratio of 10:3:1 (ball-to-powder ratio 5:1). Stearic acid is then added at 1.0% of the total powder mass. The mixture is first ball-milled at 200 rpm for 8 hours, then the speed is adjusted to 310 rpm for intermittent ball milling for 1 hour. During intermittent ball milling, the milling is paused for 10 minutes after a 30-minute pause. Then, the mixture is dry-mixed at 300 rpm for 3 hours under a high-purity argon atmosphere. The resulting mixed powder is then subjected to hydrogen plasma treatment at 120W for 10 minutes. Finally... The plasma-treated mixed powder was placed in a ceramic boat, pushed into a tube furnace, sealed, evacuated, and purged with nitrogen. This process was repeated three times to complete the gas replacement. The temperature was then raised to 800°C at a rate of 5°C / min. A mixed carbon source of methanol and ethanol, with a volume ratio of methanol to ethanol of 4:1, was introduced. By adjusting the carbon source flow rate, 2-5 layers of graphene were ensured to be formed, which is beneficial for interfacial bonding. The mixture was held at this temperature for 30 minutes, then cooled to room temperature, and the product was removed. This process first synthesizes a composite phase of tungsten carbide, cobalt, and nano-cerium dioxide, the surface of which has nano-defects due to plasma etching. The pit provides growth sites for graphene nucleation. Graphene sheets synthesized with a carbon source then coat the composite phase, forming a core-shell structure with outer wrinkles. The core-shell composite phase provides basic hardness, while the graphene shell prevents crack propagation through crack deflection and bridging effects. The graphene shell can also form a transfer film during friction, reducing the coefficient of friction and reducing direct wear by encapsulating the composite phase. The chemical inertness and dense structure of graphene also help to hinder the penetration of corrosive media. Therefore, its use in tungsten-based cemented carbides can significantly improve bending strength, wear resistance, and corrosion resistance. Among these, cerium dioxide sodium... The cerium dioxide nanoparticles, anchored within the tungsten carbide grain boundaries and cobalt binder phase, not only form a semi-coherent interface, increasing the interfacial bonding energy and requiring additional energy for crack propagation, but also inhibit grain growth at high temperatures, thus refining the grains and strengthening the composite phase. Furthermore, the cerium dioxide nanoparticles effectively fill the pores of the tungsten carbide-cobalt pair, blocking corrosion channels. Moreover, the oxygen vacancies in cerium dioxide promote the decomposition of the carbon source, resulting in a more uniform graphene coverage. The cerium dioxide nanoparticles can also prevent the graphene shell from slipping during sintering, improving the stability of the coating layer, thus yielding a graphene-coated core-shell composite powder. S2. The tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and the graphene-coated core-shell composite powder described in step S1 are mixed uniformly by wet ball milling. During ball milling, the material-to-ball ratio is 5:1, the rotation speed is 250 rpm, the time is 3 hours, and the mixture is vacuum dried at 60℃. The mixture is then placed in a mold and pressed into a green body under 300 MPa. The green body is placed in a pyrophyllite mold and sintered under high temperature and high pressure using a six-sided press, with argon gas introduced for protection. The temperature is first raised to 800℃ for 1 minute, then raised to 1200℃, the sintering pressure is fixed at 5 GPa, and the holding time is 4 minutes. The sample is then removed, polished, and the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers are further processed. The nanofibers and graphene-coated core-shell composite powder form a physical anchoring effect through mechanical interlocking. Furthermore, the dangling bonds such as C=O and C-OH at the edges of the graphene can react with tungsten carbide or cobalt to form WC or Co-C bonds, enhancing interfacial bonding. External stress is effectively transferred through the interface, avoiding local stress concentration and improving bending strength. At the same time, it further enhances the chemical inert barrier protection, effectively isolating corrosive media and enhancing corrosion resistance. Moreover, the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder synergistically construct a multi-scale lubrication system, reducing material wear and obtaining a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide.

[0035] Comparative Example 1 This comparative example provides a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, which differs from Example 1 in that the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers do not contain sodium molybdate dihydrate or thiourea; the preparation method of the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers does not include step (3); the preparation method of the highly corrosion-resistant and wear-resistant tungsten-based cemented carbide is the same as that of Example 1.

[0036] Comparative Example 2 This comparative example provides a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, which differs from Example 1 in that the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers do not contain boron nitride or Dow Corning Z-6020 silane coupling agent; the preparation method of the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers does not include step (4); the preparation method of the highly corrosion-resistant and wear-resistant tungsten-based cemented carbide is the same as that of Example 1.

[0037] Comparative Example 3 This comparative example provides a highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, which differs from Example 1 in that the graphene-coated core-shell composite powder does not contain nano-cerium dioxide powder; the preparation method of the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers is the same as in Example 1; and nano-cerium dioxide powder is not added in step S1 of the preparation method of the highly corrosion-resistant and wear-resistant tungsten-based cemented carbide.

[0038] Experimental Example 1 Mechanical property test Test samples: High corrosion-resistant and wear-resistant tungsten-based cemented carbides prepared in Examples 1-4 and Comparative Examples 1-3.

[0039] Test method: According to the standard GB / T6569-1986, the flexural strength of the test sample was tested using a universal testing machine. The sample size was 3mm×4mm×35mm, the span was 30mm, and the loading speed was 0.5mm / min.

[0040] Figure 2 The figures show the bending strength results of Examples 1-4 and Comparative Examples 1-3. As shown, the bending strength of Examples 1-4 is 4206-4520 MPa, indicating good bending strength; the bending strength of Comparative Examples 1-3 is 2685-3257 MPa, indicating average bending strength. The tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers of Comparative Example 1 do not contain sodium molybdate dihydrate or thiourea, thus failing to form a molybdenum disulfide coating layer on the surface of the tungsten-based composite oxide nanofibers, failing to impart toughness, resulting in average bending strength; the tungsten-based composite oxide@... The molybdenum disulfide and boron nitride hybrid nanofibers do not contain boron nitride or Dow Corning Z-6020 silane coupling agent, making it impossible to anchor boron nitride to the molybdenum disulfide surface. This is not conducive to filling the defects on the fiber surface, and thus cannot reduce stress concentration, resulting in general bending strength. The graphene-coated core-shell composite powder in Comparative Example 3 does not contain nano-cerium dioxide powder, and cannot be pinned to the tungsten carbide grain boundaries and cobalt binder phase to form a semi-coherent interface. This makes cracks easy to propagate and is not conducive to preventing the slippage of the graphene layer during sintering. This limits the crack deflection and bridging effect of graphene, resulting in general bending strength.

[0041] Experiment Example 2 Abrasion resistance test Test samples: High corrosion-resistant and wear-resistant tungsten-based cemented carbides prepared in Examples 1-4 and Comparative Examples 1-3.

[0042] Test Method: The wear performance of the test samples was tested using a UMT-Tribolbab ball-and-disc friction tester. Si3N4 balls with a diameter of 6.35 mm were used as the friction pair material. The sliding test load (F) was 10 N, the rotation speed (R) was 364 r / min, the rotation radius (d) was 3.5 mm, and the test time (T) was 60 min. The total wear volume (Vm) of the sample was measured using an Alphastep P-7 probe contact profilometer, and the volumetric wear rate (mm) of the coating was calculated using the following formula. 3 / N·m): Volumetric wear rate (mm) 3 / N·m)=Vm / (3.14×F×d×R×T) Figure 3The graph shows the volumetric wear rate results for Examples 1-4 and Comparative Examples 1-3; as shown, the volumetric wear rate for Examples 1-4 is 1.9-3.0 × 10⁻⁶. -5 mm 3 / N·m indicates strong wear resistance; the volumetric wear rate of comparative examples 1-3 is 5.1-6.3×10 - 5 mm 3 / N·m indicates weak wear resistance; Comparative Example 1's tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers do not contain sodium molybdate dihydrate or thiourea, thus failing to form a lubricating molybdenum disulfide coating layer, which is detrimental to reducing the friction coefficient and surface wear, and also hinders the formation of a protective film on the material surface, increasing the risk of frictional contact with the fiber core, resulting in weak wear resistance; Comparative Example 2's tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers do not contain boron nitride or Dow Corning Z-6020 silane coupling agent, thus failing to anchor boron nitride to the molybdenum disulfide surface to exert its hardening properties, directly limiting the role of the hardening-enhancing phase, resulting in weak wear resistance; Comparative Example 3's graphene-coated core-shell composite powder does not contain nano-cerium dioxide powder, thus failing to exert the grain refinement and composite phase strengthening effects, and also hindering the coating stability of graphene, increasing the risk of direct wear of the composite phase, resulting in weak wear resistance.

[0043] Experimental Example 3 Corrosion resistance test Test samples: High corrosion-resistant and wear-resistant tungsten-based cemented carbides prepared in Examples 1-4 and Comparative Examples 1-3.

[0044] Test method: The test sample was ultrasonically cleaned sequentially with acetone and anhydrous ethanol for 10 min, vacuum dried at 80℃ for 2 h, cooled to room temperature, and the initial mass W0 (accurate to 0.01 mg) was recorded. The surface area S (cm²) of the sample was also measured. 2 Then, according to GB / T10125-2021, the test was carried out using a YWX / Q-150 salt spray test chamber. A 5% NaCl aqueous solution (adjusted to pH 7) was prepared as the corrosion solution. The test sample was completely immersed in the corrosion solution. After 500 hours, it was removed, rinsed with deionized water, ultrasonically vibrated for 5 minutes, vacuum dried at 80℃ for 2 hours, and cooled to room temperature. The final mass W1 (accurate to 0.01 mg) was recorded. The mass loss rate (mg / cm³) was calculated according to the following formula. 2 ): mass loss rate (mg / cm) 2 = (W0-W1) / S Figure 4 The graph shows the mass loss rate results for Examples 1-4 and Comparative Examples 1-3; as shown, the mass loss rate for Examples 1-4 is 0.02-0.05 mg / cm³. 2This indicates good corrosion resistance; the mass loss rate of comparative examples 1-3 was 0.12-0.18 mg / cm³. 2 The results indicate that the corrosion resistance is generally average. Comparative Example 1, containing tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers, lacks sodium molybdate dihydrate and thiourea, making it unable to form a passivation layer through molybdenum disulfide. This hinders the blocking of corrosive media penetration, resulting in generally average corrosion resistance. Comparative Example 2, also containing tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers, lacks boron nitride and Dow Corning Z-6020 silane coupling agent, preventing the anchoring of boron nitride to the molybdenum disulfide surface to form a dense barrier. This hinders the reduction of corrosive media penetration, resulting in generally average corrosion resistance. Comparative Example 3, containing graphene-coated core-shell composite powder, lacks nano-cerium dioxide powder, failing to fill the pores of the tungsten carbide-cobalt layer to block corrosion channels. This also hinders the uniformity and stability of graphene coating, limiting the barrier effect of graphene on corrosive media, resulting in generally average corrosion resistance.

[0045] The above experimental results show that the mechanical properties, wear resistance, and corrosion resistance of Examples 1-4 of the present invention are significantly better than those of Comparative Examples 1-3. Among them, Example 1, which uses tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder, has better bending strength, stronger wear resistance, and better corrosion resistance. High-temperature sintering of tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and graphene-coated core-shell composite powder enhances the interfacial bonding between the two through physical anchoring and chemical bonding, reduces defects, effectively transfers external stress, strengthens the barrier protection effect, fully isolates the penetration of corrosive media, and constructs a multi-scale lubrication system to reduce the wear of substances such as tungsten carbide and cobalt, thereby significantly enhancing bending strength, corrosion resistance, and wear resistance.

[0046] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

[0047] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention. The actual application is not limited to this. In conclusion, if those skilled in the art are inspired by this description and design similar methods and embodiments without departing from the spirit of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A highly corrosion-resistant and wear-resistant tungsten-based cemented carbide, characterized in that: The high corrosion-resistant and wear-resistant tungsten-based cemented carbide comprises the following components in parts by weight: 20-30 parts of tungsten-based composite oxide@molybdenum disulfide and boron nitride hybrid nanofibers, and 80-90 parts of graphene-coated core-shell composite powder; the graphene-coated core-shell composite powder is a core-shell structure powder obtained by first ball milling and plasma activation treatment of tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder, and then growing a graphene coating layer in situ on the surface; The preparation method of the tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers specifically includes the following steps: (1) Dissolve 1.0-1.2g of copper nitrate trihydrate and 0.4-0.6g of nickel nitrate hexahydrate in 15mL of deionized water and stir for 0.5-1h to form solution I for later use. Then dissolve 0.8-1.0g of trimesic acid in 25mL of anhydrous ethanol and stir for 0.5-1h to form solution II for later use. Then mix solution I and solution II and add 0.2-0.4g of polyvinylpyrrolidone. Stir evenly and place in a reaction vessel at 110-120℃ for hydrothermal reaction for 10-12h. Wash the product with anhydrous ethanol 3-5 times and vacuum dry at 60℃ to obtain copper-nickel bimetallic MOF nanoparticles. (2) Disperse the copper-nickel bimetallic MOF nanoparticles described in step (1) in 6 mL of N,N-dimethylformamide solvent, sonicate for 30-50 min, then add ammonium metatungstate and polyvinylpyrrolidone, stir for 20-30 min to obtain the precursor spinning solution, use electrospinning technology, set the voltage to 10-18 kV and the feed rate to 0.03-0.05 mm / s, put the collected fibers into a crucible, dry them at 50-60℃ for 1-2 h, and then calcine them in air at 500-550℃ with a heating rate of 1℃ / min for 1-2 h to obtain tungsten-based composite oxide nanofibers; (3) Dissolve sodium molybdate dihydrate and thiourea in 30 mL of deionized water, then add the tungsten-based composite oxide nanofibers described in step (2), ultrasonically disperse for 10-20 min, adjust the pH to 4.0, and then react at 180-200 °C for 10-12 h. Wash the product with 80% ethanol solution 3-5 times, vacuum dry at 60 °C, and then anneal at 350-400 °C for 1-2 h in an atmosphere of 2% hydrogen and 98% argon to obtain tungsten-based composite oxide@molybdenum disulfide nanofibers. (4) Disperse 0.08-0.1g of boron nitride in 20mL of 90% ethanol solution, add 0.4-0.5mL of Dow Corning Z-6020 silane coupling agent, sonicate for 40-50min to obtain boron nitride suspension for later use, then immerse the tungsten-based composite oxide@molybdenum disulfide nanofibers obtained in step (3) into the boron nitride suspension, stir at 50-60℃ for 1-2h, vacuum dry at 80℃, and finally anneal at 300-320℃ for 0.5-1h to obtain tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers.

2. A method for preparing a high corrosion-resistant and wear-resistant tungsten-based cemented carbide according to claim 1, characterized in that: Specifically, the following steps are included: S1. Tungsten carbide powder, cobalt powder, and nano-cerium dioxide powder are loaded into a ball mill jar in a mass ratio of 10:3:1-2, with a ball-to-powder ratio of 5:

1. Stearic acid is then added at 0.8-1.0% of the total powder mass. The mixture is first ball-milled at 180-200 rpm for 8-10 hours, then the speed is adjusted to 280-310 rpm for intermittent ball milling for 1-2 hours. During intermittent ball milling, the mixture is milled for 30 minutes, paused for 10 minutes, and then dry-mixed at 300 rpm for 3-4 hours. The mixture is then mixed with high-purity argon. Using a protective atmosphere, the resulting mixed powder is subjected to hydrogen plasma treatment at a power of 80-120W for 10-30 minutes. Finally, the plasma-treated mixed powder is placed in a ceramic boat, pushed into a tube furnace, sealed, evacuated, and purged with nitrogen. This process is repeated three times to complete the gas replacement. The temperature is then raised to 750-800℃ at a rate of 5℃ / min. A mixed carbon source of methanol and ethanol is introduced, and the temperature is maintained for 30-35 minutes. The temperature is then lowered to room temperature, and the product is removed to obtain graphene-coated core-shell composite powder. S2. The tungsten-based composite oxide@molybdenum disulfide boron nitride hybrid nanofibers and the graphene-coated core-shell composite powder described in step S1 are mixed evenly by wet ball milling. During the ball milling process, the material-to-ball ratio is 5:1, the rotation speed is 200-250 rpm, the time is 3-4 hours, and the mixture is vacuum dried at 60℃. The mixture is then placed in a mold and pressed into a green body under 300 MPa. The green body is placed in a pyrophyllite mold and sintered at high temperature and high pressure using a six-sided press, with argon gas introduced for protection. The temperature is first raised to 800℃ for 1-2 minutes, then raised to 1100-1200℃, the sintering pressure is fixed at 3-5 GPa, and the holding time is 4-8 minutes. The sample is then removed, polished, and a high corrosion-resistant and wear-resistant tungsten-based cemented carbide is obtained.

3. The method for preparing the high corrosion-resistant and wear-resistant tungsten-based cemented carbide according to claim 2, characterized in that: In step S1, the volume ratio of methanol to ethanol in the methanol and ethanol mixed carbon source is 3-4:

1.

4. The method for preparing the high corrosion-resistant and wear-resistant tungsten-based cemented carbide according to claim 3, characterized in that: In step (2), the amount of ammonium metatungstate added is 1.0-2.0g, and the amount of polyvinylpyrrolidone added is 0.8-1.0g.

5. The method for preparing the high corrosion-resistant and wear-resistant tungsten-based cemented carbide according to claim 4, characterized in that: In step (3), the amounts of sodium molybdate dihydrate and thiourea added are 0.3-0.5g and 0.6-0.8g, respectively.

6. The method for preparing the high corrosion-resistant and wear-resistant tungsten-based cemented carbide according to claim 5, characterized in that: In step (4), the brand name of Dow Corning Z-6020 silane coupling agent is OFS-6020.

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