High-strength cemented carbide material and method for producing the same

Abstract

This invention relates to the field of cemented carbide materials technology, specifically disclosing a high-strength cemented carbide material and its preparation method, comprising the following raw materials in parts by weight: 5-8 parts cobalt powder, 86-90 parts tungsten carbide powder, 2.4-2.8 parts reinforcing components, and 0.5-0.7 parts modifiers. The preparation method of the high-strength cemented carbide material includes the following steps: step S1, preparation of premix; step S2, spray granulation; step S3, compaction; and step S4, spark plasma sintering. This invention incorporates reinforcing components and modifiers. The reinforcing components contain aluminum dihydrogen phosphate, silica sol, cerium oxide, zirconium oxide, tantalum carbide, molybdenum carbide, and titanium dioxide gel, which not only possess excellent physical properties themselves but also form hydrogen bonds with the modifiers, synergistically improving the overall performance of the cemented carbide material.

Description

Technical Field

[0001] This invention relates to the field of cemented carbide materials technology, and more specifically, to a high-strength cemented carbide material and its preparation method. Background Technology

[0002] WC-Co cemented carbide is a composite material made using powder metallurgy with WC (a refractory hard metal compound) as the base and Co (a transition metal element) as the binder phase. It possesses high hardness, high strength, and high wear resistance, and is widely used in wear-resistant, corrosion-resistant, and high-temperature-resistant tools. Among these, nano-WC-Co cemented carbide, due to its superior machinability and ability to meet higher industrial requirements, has become a hot research topic.

[0003] However, nanocrystals tend to grow rapidly during the sintering process, leading to a decrease in the properties of the prepared cemented carbide. To prevent grain growth, existing techniques often add nano-sized vanadium carbide; however, nano-sized vanadium carbide reduces the ability of the cobalt phase to wet tungsten carbide, resulting in a decrease in the mechanical properties of the prepared nano-WC-Co cemented carbide. Summary of the Invention

[0004] To address the problems mentioned in the background section, this invention provides a high-strength cemented carbide material and its preparation method, the specific technical solution of which is as follows: A high-strength cemented carbide material comprises the following raw materials in parts by weight: 5-8 parts cobalt powder, 86-90 parts tungsten carbide powder, 2.4-2.8 parts reinforcing components, and 0.5-0.7 parts modifier and refiner; A method for preparing a high-strength cemented carbide material includes the following steps: Step S1: Preparation of premix: Cobalt powder, tungsten carbide powder, reinforcing components, and modifier / refining agent are added to anhydrous ethanol according to weight parts, ball-milled, dried, and sieved to obtain the premix. The ball-milling conditions are: ball-to-material ratio of 5-7:1, rotation speed of 70-80 rpm, and ball-milling time of 14-20 h; the drying conditions are: drying at 84-90℃ for 5.4-6 h; and the sieve mesh size is 260-300 mesh. Step S2, spray granulation: The premix prepared in step S1 is spray dried and granulated to obtain granulated premix; Step S3, pressing: The granulated premix obtained in step S2 is pressed into a green body. Step S4, Spark Plasma Sintering: The green blank prepared in step S3 is subjected to plasma sintering to obtain a high-strength cemented carbide material.

[0005] Furthermore, in step S1, the mass ratio of tungsten carbide powder to deionized water is 1.6-2:1.

[0006] Furthermore, in step S3, the pressing pressure is 270-280 MPa.

[0007] Furthermore, in step S4, the discharge plasma sintering process specifically involves: heating to 1350-1380°C at a rate of 125°C / min under argon protection and a sintering pressure of 50-60 MPa, and holding at that temperature for 8-12 minutes.

[0008] Furthermore, the reinforcing component is prepared by the following steps: Step A1: Add cerium oxide to sulfuric acid solution, stir evenly, add thickening component, heat to 56-60℃, stir and react for 3.6-4.4h, filter, wash and dry to obtain pretreated cerium oxide, wherein the mass ratio of cerium oxide, sulfuric acid solution and thickening component is 2.2-3.4:46-52:4-6; Step A2: Add pretreated cerium oxide, zirconium oxide, tantalum carbide, and molybdenum carbide to the mixed acid, stir evenly, adjust the pH to 8-9, stir for 28-34 min, heat to 92-108℃, stir and react for 2-3 h, cool to room temperature to obtain modified cerium oxide. The mass ratio of pretreated cerium oxide, zirconium oxide, tantalum carbide, molybdenum carbide, and mixed acid is 1-3:0.04-0.06:0.01-0.03:0.022-0.034:45-55. Step A3: Mix the modified cerium oxide and crosslinking agent evenly, add tetrabutyl titanate and anhydrous ethanol, heat to 50-60℃, stir and react for 3.6-4.2h, wash and dry to obtain the reinforcing component, wherein the mass ratio of modified cerium oxide, crosslinking agent, tetrabutyl titanate and anhydrous ethanol is 3.6-4.8:2.2-2.6:0.44-0.52:20-30.

[0009] Furthermore, in step A1, the mass fraction of the sulfuric acid solution is 36-40%.

[0010] Furthermore, in step A2, the mixed acid is prepared by mixing hydrofluoric acid and concentrated nitric acid in a mass ratio of 2-4:3.

[0011] Furthermore, in step A3, the crosslinking agent is propylene oxide butyl ether.

[0012] Furthermore, the thickening component is prepared by the following steps: Aluminum dihydrogen phosphate was added to water to prepare a 50% aluminum dihydrogen phosphate solution, which was then transferred to a high-speed disperser. Silica sol and chromium oxide were added and stirred until homogeneous to obtain a thickening component. The mass ratio of aluminum dihydrogen phosphate solution, silica sol and chromium oxide was 36-40:3.6-4.2:0.02-0.04.

[0013] Furthermore, the refining agent is prepared by the following steps: Step B1: Sodium chromate aqueous solution, sodium acetate solution and polypyrrolidone aqueous solution are ultrasonically dispersed evenly. Under nitrogen protection, the temperature is raised to 210-220℃ and the reaction is stirred for 18-22 hours. After centrifugation, the precipitate is washed and dried to obtain hydroxylated chromium oxide. The mass ratio of sodium chromate aqueous solution, sodium acetate aqueous solution and polypyrrolidone aqueous solution is 1:1.2-1.4:62-66. Step B2: Hydroxylated chromium oxide is ultrasonically dispersed in Tris-HCl buffer, dopamine hydrochloride and vanadium nitrate are added, the temperature is raised to 60-70℃, and the reaction is stirred for 4-6 hours to obtain the modified refining agent. The mass ratio of hydroxylated chromium oxide, Tris-HCl buffer, dopamine hydrochloride and vanadium nitrate is 2.6-3.4:120-160:1.4-1.6:0.4-0.6.

[0014] Furthermore, in step B1, the mass fraction of the sodium chromate aqueous solution is 16-18%.

[0015] Furthermore, in step B1, the mass fraction of the sodium acetate solution is 12-14%.

[0016] Furthermore, in step B1, the mass fraction of the polypyrrolidone aqueous solution is 3.2-3.6%.

[0017] Furthermore, in step B2, the pH of the Tris-HCl buffer solution is 7-9.

[0018] Compared with the prior art, the present invention has the following beneficial effects: (1) In the technical solution of the present invention, aluminum dihydrogen phosphate and silica sol can not only be adsorbed on the surface of cerium oxide by electrostatic adsorption or chemical bonding to form a steric hindrance layer, but also adsorb zirconium oxide, tantalum carbide and molybdenum carbide onto the surface of pretreated cerium oxide as synthesis sites for zirconium oxide, tantalum carbide and molybdenum carbide. Among them, nano-cerium oxide can significantly reduce the grain size in the sintered cemented carbide and avoid the formation of pores caused by grain coarsening. Zirconia can not only strengthen through grain refinement and toughen through phase transformation, but also delay crack propagation through crack deflection and bridging mechanisms. Tantalum carbide can not only promote crack bifurcation and grain boundary slip, but also refine tungsten carbide grains. Molybdenum carbide can not only improve the comprehensive performance of cemented carbide materials through mechanisms such as inhibiting WC grain growth and solid solution strengthening, but also serve as a stable carbide reinforcing phase. Through the effects of the above substances, the hardness, toughness, impact resistance and wear resistance of cemented carbide materials can be improved.

[0019] (2) In the technical solution of the present invention, modified cerium oxide is embedded into the titanium dioxide gel network structure to fix the modified cerium oxide, thereby improving the dispersion and compatibility of modified cerium oxide in the ultra-coarse-grained WC-Co cemented carbide. At the same time, the titanium dioxide gel can not only improve the strength and hardness of the cemented carbide by refining and pinning WC grains, but also the titanium dioxide in the titanium dioxide gel can react with tungsten carbide to generate titanium carbide with high hardness. They are dispersed in the matrix and can jointly bear the external load, further improving the hardness and toughness of the cemented carbide.

[0020] (3) In the technical solution of the present invention, the prepared hydroxylated chromium oxide is mixed evenly with dopamine hydrochloride and vanadium nitrate to obtain a modifier and refiner. The nano-sized chromium carbide generated by the calcination and reduction of hydroxylated chromium oxide can precipitate at the grain boundaries of tungsten carbide, which plays a role in pinning the grain boundaries, inhibiting the grain boundary diffusion and surface diffusion of tungsten carbide grains, and improving the hardness, toughness, impact resistance and wear resistance of cemented carbide materials. In addition, hydroxylated chromium oxide can also form hydrogen bond interaction with the hydroxyl groups on the surface of the reinforcing component, which improves the compatibility and the hardness, toughness, impact resistance and wear resistance of cemented carbide materials. Dopamine hydrochloride can form a three-dimensional network structure of polydopamine under the catalysis of vanadium nitrate, which then encapsulates the hydroxylated chromium oxide particles to prevent them from agglomerating, thereby improving the dispersion performance. At the same time, vanadium carbide generated by the high-temperature calcination and carbonization of vanadium nitrate can work synergistically with chromium carbide generated by the calcination and carbonization of hydroxylated chromium oxide as a refiner. When introduced into cemented carbide materials, it can work synergistically with the reinforcing component to jointly improve the hardness, toughness, impact resistance and wear resistance of cemented carbide materials. Detailed Implementation

[0021] To make the implementation methods of this application easier to understand, the application will be described in detail below with reference to specific embodiments. These embodiments are for illustrative purposes only and are not limited to the application scope of this application.

[0022] Where specific techniques or conditions are not specified in the examples, they shall be performed in accordance with the techniques or conditions described in the literature in this field, or in accordance with the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased through legitimate channels.

[0023] The tungsten carbide powder is nano-tungsten carbide powder commercially available from Shijiazhuang Jinghuang Technology Co., Ltd., CAS number 12070-12-1; the cobalt powder is commercially available from Hubei Langbowan Biomedical Co., Ltd., CAS number [missing information]. 7440-48-4; Cerium oxide powder is nano-cerium oxide powder commercially available from Ganzhou Tejing New Material Technology Co., Ltd., CAS number 1306-38-3; Zirconia is nano-zirconia powder with an average particle size of 30nm commercially available from Qinghe County Chaotai Metal Material Co., Ltd.; Tantalum carbide is nano-tantalum carbide powder commercially available from Hebei Yinbai Alloy Welding Material Co., Ltd., grade TaC-1; Molybdenum carbide is nano-molybdenum carbide powder commercially available from Nangong City Xingjiu New Material Technology Co., Ltd.; Yttrium oxide is nano-yttrium oxide powder with a particle size of 50nm commercially available from Hebei Guangtuo Welding Material Co., Ltd.; Silica sol is industrial silica sol with an effective content of 40% commercially available from Shandong Xiangzhao New Material Co., Ltd.

[0024] The present invention will be further described in detail below with reference to embodiments and comparative examples.

[0025] Example 1 This embodiment provides a high-strength cemented carbide material, comprising the following raw materials in parts by weight: 5 parts cobalt powder, 86 parts tungsten carbide powder, 2.4 parts reinforcing component, and 0.5 parts modifier and refiner; A method for preparing a high-strength cemented carbide material includes the following steps: Step S1, Preparation of premix: Cobalt powder, tungsten carbide powder, reinforcing components and modifiers are added to anhydrous ethanol according to the weight ratio, ball milling is carried out at 80 rpm for 20 h, and then dried at 84℃ for 6 h. The mixture is then passed through a 260 mesh sieve to obtain the premix, wherein the mass ratio of tungsten carbide powder to deionized water is 1.6:1. Step S2, spray granulation: The premix prepared in step S1 is spray dried and granulated to obtain granulated premix; Step S3, pressing: The granulated premix obtained in step S2 is pressed into a green body at 270 MPa. Step S4, Spark Plasma Sintering: The green blank prepared in step S3 is subjected to plasma sintering to obtain a high-strength cemented carbide material. Specifically, the spark plasma sintering process is as follows: under argon protection and a sintering pressure of 50 MPa, the temperature is raised to 1350℃ at a rate of 125℃ / min and held for 12 min. The reinforcing component is prepared by the following steps: Step A1: Add cerium oxide to a 36% sulfuric acid solution and stir at 540 rpm for 40 minutes until homogeneous. Add the thickening agent, heat to 56°C, and stir for 4.4 hours. After filtration, wash three times each with anhydrous ethanol and deionized water, and dry at 58°C to constant weight to obtain pretreated cerium oxide. The mass ratio of cerium oxide, sulfuric acid solution, and thickening agent is 2.2:46:4. Step A2: Add pretreated cerium oxide, zirconium oxide, tantalum carbide, and molybdenum carbide to the mixed acid, stir at 600 rpm for 28 min until homogeneous, adjust the pH to 8 with 0.2M ammonia solution, maintain the stirring speed, continue stirring for 34 min, raise the temperature to 92℃, stir and react for 3 h, cool to room temperature to obtain modified cerium oxide. The mass ratio of pretreated cerium oxide, zirconium oxide, tantalum carbide, molybdenum carbide, and mixed acid is 1:0.04:0.01:0.022:45, and the mixed acid is composed of hydrofluoric acid and concentrated nitric acid mixed at a mass ratio of 2:3. Step A3: Modified cerium oxide and propylene oxide butyl ether are stirred at 640 rpm for 18 min until homogeneous. Tetrabutyl titanate and anhydrous ethanol are added, the temperature is raised to 50℃, and the mixture is stirred for 4.2 h. The mixture is washed three times with deionized water and dried at 58℃ to constant weight to obtain the reinforcing component. The mass ratio of modified cerium oxide, propylene oxide butyl ether, tetrabutyl titanate, and anhydrous ethanol is 3.6:2.2:0.44:20. The thickening component is prepared by the following steps: Aluminum dihydrogen phosphate was added to water to prepare a 50% (w / w) aluminum dihydrogen phosphate solution, which was then transferred to a high-speed disperser. Silica sol and chromium oxide were added, and the mixture was stirred at 1100 rpm for 36 minutes until homogeneous to obtain the thickening component. The mass ratio of aluminum dihydrogen phosphate solution, silica sol, and chromium oxide was 36:3.6:0.02. The refining agent is prepared by the following steps: Step B1: A 16% sodium chromate aqueous solution, a 12% sodium acetate solution, and a 3.2% polypyrrolidone aqueous solution were ultrasonically dispersed at a frequency of 30 kHz and a power of 500 W for 36 min. Under nitrogen protection, the mixture was heated to 210 °C and stirred for 22 h. After centrifugation, the precipitate was washed with deionized water until neutral and dried at 66 °C to constant weight to obtain hydroxylated chromium oxide. The mass ratio of the sodium chromate aqueous solution, the sodium acetate aqueous solution, and the polypyrrolidone aqueous solution was 1:1.2:62. Step B2: Hydroxylated chromium oxide was ultrasonically dispersed in a Tris-HCl buffer solution at pH 7. The ultrasonic frequency was controlled at 25 kHz and the ultrasonic power at 450 W. The mixture was ultrasonicated for 40 min until it was uniformly dispersed. Dopamine hydrochloride and vanadium nitrate were added, and the temperature was raised to 60 °C. The mixture was stirred at 630 rpm for 6 h to obtain the modified refining agent. The mass ratio of hydroxylated chromium oxide, Tris-HCl buffer solution, dopamine hydrochloride and vanadium nitrate was 2.6:120:1.4:0.4.

[0026] Example 2 This embodiment provides a high-strength cemented carbide material, comprising the following raw materials in parts by weight: 6.5 parts cobalt powder, 88 parts tungsten carbide powder, 2.6 parts reinforcing component, and 0.6 parts modifier and refiner; A method for preparing a high-strength cemented carbide material includes the following steps: Step S1, Preparation of premix: Cobalt powder, tungsten carbide powder, reinforcing components and modifiers are added to anhydrous ethanol according to the weight ratio, ball milling is performed at 75 rpm for 17 h, and then dried at 87℃ for 5.6 h; the mixture is then passed through a 280-mesh sieve to obtain the premix, wherein the mass ratio of tungsten carbide powder to deionized water is 1.8:1; Step S2, spray granulation: The premix prepared in step S1 is spray dried and granulated to obtain granulated premix; Step S3, pressing: The granulated premix obtained in step S2 is pressed into a green body at 275 MPa. Step S4, Spark Plasma Sintering: The green blank prepared in step S3 is subjected to plasma sintering to obtain a high-strength cemented carbide material. Specifically, the spark plasma sintering process is as follows: under argon protection and a sintering pressure of 55 MPa, the temperature is raised to 1365°C at a rate of 125°C / min and held for 10 min. The reinforcing component is prepared by the following steps: Step A1: Add cerium oxide to a 38% sulfuric acid solution and stir at 560 rpm for 36 minutes until homogeneous. Add the thickening agent, heat to 58°C, maintain the stirring speed, and continue stirring for 4 hours. After filtration, wash with anhydrous ethanol and deionized water four times each, and dry at 62°C to constant weight to obtain pretreated cerium oxide. The mass ratio of cerium oxide, sulfuric acid solution, and thickening agent is 2.8:49:5. Step A2: Add pretreated cerium oxide, zirconium oxide, tantalum carbide, and molybdenum carbide to the mixed acid, stir at 640 rpm for 24 min until homogeneous, adjust the pH to 8.5 with 0.4M ammonia solution, maintain the stirring speed, continue stirring for 31 min, heat to 100℃, stir and react for 2.5 h, cool to room temperature to obtain modified cerium oxide. The mass ratio of pretreated cerium oxide, zirconium oxide, tantalum carbide, molybdenum carbide, and mixed acid is 2:0.05:0.02:0.028:50. The mixed acid is composed of hydrofluoric acid and concentrated nitric acid mixed in a mass ratio of 1:1. Step A3: Modified cerium oxide and propylene oxide butyl ether were stirred at 660 rpm for 16 min until homogeneous. Tetrabutyl titanate and anhydrous ethanol were added, the temperature was raised to 55℃, and the mixture was stirred for 3.9 h. The mixture was washed four times with deionized water and dried at 60℃ to constant weight to obtain the reinforcing component. The mass ratio of modified cerium oxide, propylene oxide butyl ether, tetrabutyl titanate, and anhydrous ethanol was 4.2:2.4:0.48:25. The thickening component is prepared by the following steps: Aluminum dihydrogen phosphate was added to water to prepare a 50% (w / w) aluminum dihydrogen phosphate solution, which was then transferred to a high-speed disperser. Silica sol and chromium oxide were added, and the mixture was stirred at 1200 rpm for 30 minutes until homogeneous to obtain the thickening component. The mass ratio of aluminum dihydrogen phosphate solution, silica sol, and chromium oxide was 38:3.9:0.03. The refining agent is prepared by the following steps: Step B1: A 17% sodium chromate aqueous solution, a 13% sodium acetate solution, and a 3.4% polypyrrolidone aqueous solution were ultrasonically dissolved at a frequency of 25 kHz and a power of 450 W for 42 min until uniformly dispersed. Under nitrogen protection, the mixture was heated to 215 °C and stirred for 20 h. After centrifugation, the precipitate was washed with deionized water until neutral and dried at 70 °C to constant weight to obtain hydroxylated chromium oxide. The mass ratio of the sodium chromate aqueous solution, the sodium acetate aqueous solution, and the polypyrrolidone aqueous solution was 1:1.3:64. Step B2: Hydroxylated chromium oxide was ultrasonically dispersed in a Tris-HCl buffer solution at pH 8. The ultrasonic frequency was controlled at 30 kHz and the ultrasonic power at 500 W. The mixture was ultrasonicated for 36 min until it was uniformly dispersed. Dopamine hydrochloride and vanadium nitrate were added, and the temperature was raised to 65 °C. The mixture was stirred at 660 rpm for 5 h to obtain the modified refining agent. The mass ratio of hydroxylated chromium oxide, Tris-HCl buffer solution, dopamine hydrochloride and vanadium nitrate was 3:140:1.5:0.5.

[0027] Example 3 This embodiment provides a high-strength cemented carbide material, comprising the following raw materials in parts by weight: 8 parts cobalt powder, 90 parts tungsten carbide powder, 2.8 parts reinforcing component, and 0.7 parts modifier and refiner; A method for preparing a high-strength cemented carbide material includes the following steps: Step S1, Preparation of premix: Cobalt powder, tungsten carbide powder, reinforcing components and modifiers are added to anhydrous ethanol according to the weight ratio, ball milling is performed at 70 rpm for 14 h, and then dried at 90℃ for 5.4 h. The mixture is then passed through a 300-mesh sieve to obtain the premix, wherein the mass ratio of tungsten carbide powder to deionized water is 2:1. Step S2, spray granulation: The premix prepared in step S1 is spray dried and granulated to obtain granulated premix; Step S3, pressing: The granulated premix obtained in step S2 is pressed into a green body at 280 MPa. Step S4, Spark Plasma Sintering: The green blank prepared in step S3 is subjected to plasma sintering to obtain a high-strength cemented carbide material. Specifically, the spark plasma sintering process is as follows: under argon protection and a sintering pressure of 60 MPa, the temperature is raised to 1380°C at a rate of 125°C / min and held for 8 min. The reinforcing component is prepared by the following steps: Step A1: Add cerium oxide to a 40% sulfuric acid solution and stir at 580 rpm for 32 minutes until homogeneous. Add the thickening component, heat to 60°C, and stir for 3.6 hours. After filtration, wash with anhydrous ethanol and deionized water five times each, and dry at 66°C to constant weight to obtain pretreated cerium oxide. The mass ratio of cerium oxide, sulfuric acid solution, and thickening component is 3.4:52:6. Step A2: Add pretreated cerium oxide, zirconium oxide, tantalum carbide, and molybdenum carbide to the mixed acid, stir at 680 rpm for 20 min until homogeneous, adjust the pH to 9 with 0.6M ammonia solution, maintain the stirring speed, continue stirring for 28 min, raise the temperature to 108℃, stir and react for 2 h, cool to room temperature to obtain modified cerium oxide. The mass ratio of pretreated cerium oxide, zirconium oxide, tantalum carbide, molybdenum carbide, and mixed acid is 3:0.06:0.03:0.034:55. The mixed acid is composed of hydrofluoric acid and concentrated nitric acid mixed at a mass ratio of 4:3. Step A3: Modified cerium oxide and propylene oxide butyl ether are stirred at 680 rpm for 14 min until uniformly mixed. Tetrabutyl titanate and anhydrous ethanol are added, the temperature is raised to 60℃, and the mixture is stirred for 3.6 h. The mixture is washed 5 times with deionized water and dried at 62℃ to constant weight to obtain the reinforcing component. The mass ratio of modified cerium oxide, propylene oxide butyl ether, tetrabutyl titanate and anhydrous ethanol is 4.8:2.6:0.52:30. The thickening component is prepared by the following steps: Aluminum dihydrogen phosphate was added to water to prepare a 50% (w / w) aluminum dihydrogen phosphate solution, which was then transferred to a high-speed disperser. Silica sol and chromium oxide were added, and the mixture was stirred at 1300 rpm for 24 minutes until homogeneous to obtain the thickening component. The mass ratio of aluminum dihydrogen phosphate solution, silica sol, and chromium oxide was 40:4.2:0.04. The refining agent is prepared by the following steps: Step B1: An 18% sodium chromate aqueous solution, a 13% sodium acetate solution, and a 3.6% polypyrrolidone aqueous solution were ultrasonicated at a frequency of 35 kHz and a power of 550 W for 30 min until uniformly dispersed. Under nitrogen protection, the mixture was heated to 220°C and stirred for 18 h. After centrifugation, the precipitate was washed with deionized water until neutral and dried at 74°C to constant weight to obtain hydroxylated chromium oxide. The mass ratio of the sodium chromate aqueous solution, the sodium acetate aqueous solution, and the polypyrrolidone aqueous solution was 1:1.4:66. Step B2: Hydroxylated chromium oxide was ultrasonically dispersed in a Tris-HCl buffer solution at pH 9. The ultrasonic frequency was controlled at 35 kHz and the ultrasonic power at 550 W. The mixture was ultrasonicated for 32 min until it was uniformly dispersed. Dopamine hydrochloride and vanadium nitrate were added, and the temperature was raised to 70 °C. The mixture was stirred at 690 rpm for 4 h to obtain the modified refining agent. The mass ratio of hydroxylated chromium oxide, Tris-HCl buffer solution, dopamine hydrochloride and vanadium nitrate was 3.4:160:1.6:0.6.

[0028] Comparative Example 1 The difference between this comparative example and Example 1 is that, in the preparation of the thickening component, chromium oxide is replaced by zirconium oxide by mass, while the remaining steps and raw materials are the same as in Example 1. The thickening component is prepared by the following steps: Aluminum dihydrogen phosphate was added to water to prepare a 50% (w / w) aluminum dihydrogen phosphate solution, which was then transferred to a high-speed disperser. Silica sol and zirconium oxide were added, and the mixture was stirred at 1100 rpm for 36 minutes until homogeneous to obtain the thickening component. The mass ratio of aluminum dihydrogen phosphate solution, silica sol, and zirconium oxide was 36:3.6:0.02.

[0029] Comparative Example 2 The difference between this comparative example and Example 1 is that, in the preparation of the reinforcing component, cerium oxide is replaced by yttrium oxide by mass, while the remaining steps and raw materials are the same as in Example 1. The reinforcing component is prepared by the following steps: Step A1: Add yttrium oxide to a 36% sulfuric acid solution and stir at 540 rpm for 40 minutes until homogeneous. Add the thickening agent, heat to 56°C, and stir for 4.4 hours. After filtration, wash three times each with anhydrous ethanol and deionized water, and dry at 58°C to constant weight to obtain pretreated yttrium oxide. The mass ratio of yttrium oxide, sulfuric acid solution, and thickening agent is 2.2:46:4. Step A2: Add pretreated yttrium oxide, zirconium oxide, tantalum carbide, and molybdenum carbide to the mixed acid, stir at 600 rpm for 28 min until homogeneous, adjust the pH to 8 with 0.2M ammonia solution, maintain the stirring speed, continue stirring for 34 min, raise the temperature to 92℃, stir and react for 3 h, cool to room temperature to obtain modified yttrium oxide. The mass ratio of pretreated yttrium oxide, zirconium oxide, tantalum carbide, molybdenum carbide, and mixed acid is 1:0.04:0.01:0.022:45, and the mixed acid is composed of hydrofluoric acid and concentrated nitric acid mixed at a mass ratio of 2:3. Step A3: Modified yttrium oxide and propylene oxide butyl ether were stirred at 640 rpm for 18 min until homogeneous. Tetrabutyl titanate and anhydrous ethanol were added, the temperature was raised to 50°C, and the mixture was stirred for 4.2 h. The mixture was washed three times with deionized water and dried at 58°C to constant weight to obtain the reinforcing component. The mass ratio of modified yttrium oxide, propylene oxide butyl ether, tetrabutyl titanate, and anhydrous ethanol was 3.6:2.2:0.44:20.

[0030] Comparative Example 3 The difference between this comparative example and Example 1 is that when preparing the reinforcing component, tetrabutyl titanate is replaced by ethyl silicate by mass, while the remaining steps and raw materials are the same as in Example 1. The reinforcing component is prepared by the following steps: Step A1: Add cerium oxide to a 36% sulfuric acid solution and stir at 540 rpm for 40 minutes until homogeneous. Add the thickening agent, heat to 56°C, and stir for 4.4 hours. After filtration, wash three times each with anhydrous ethanol and deionized water, and dry at 58°C to constant weight to obtain pretreated cerium oxide. The mass ratio of cerium oxide, sulfuric acid solution, and thickening agent is 2.2:46:4. Step A2: Add pretreated cerium oxide, zirconium oxide, tantalum carbide, and molybdenum carbide to the mixed acid, stir at 600 rpm for 28 min until homogeneous, adjust the pH to 8 with 0.2M ammonia solution, maintain the stirring speed, continue stirring for 34 min, raise the temperature to 92℃, stir and react for 3 h, cool to room temperature to obtain modified cerium oxide. The mass ratio of pretreated cerium oxide, zirconium oxide, tantalum carbide, molybdenum carbide, and mixed acid is 1:0.04:0.01:0.022:45, and the mixed acid is composed of hydrofluoric acid and concentrated nitric acid mixed at a mass ratio of 2:3. Step A3: Modified cerium oxide and propylene oxide butyl ether are stirred at 640 rpm for 18 min until uniformly mixed. The mixture is then heated to 50°C, and ethyl silicate and anhydrous ethanol are added. The mixture is stirred for 4.2 h, washed three times with deionized water, and dried at 58°C to constant weight to obtain the reinforcing component. The mass ratio of modified cerium oxide, propylene oxide butyl ether, ethyl silicate, and anhydrous ethanol is 3.6:2.2:0.44:20.

[0031] Comparative Example 4 The difference between this comparative example and Example 1 is that, in the preparation of the modifier, vanadium nitrate and other materials were replaced with chromium nitrate, while the remaining steps and raw materials were the same as in Example 1. The refining agent is prepared by the following steps: Step B1: A 16% sodium chromate aqueous solution, a 12% sodium acetate solution, and a 3.2% polypyrrolidone aqueous solution were ultrasonically dispersed at a frequency of 30 kHz and a power of 500 W for 36 min. Under nitrogen protection, the mixture was heated to 210 °C and stirred for 22 h. After centrifugation, the precipitate was washed with deionized water until neutral and dried at 66 °C to constant weight to obtain hydroxylated chromium oxide. The mass ratio of the sodium chromate aqueous solution, the sodium acetate aqueous solution, and the polypyrrolidone aqueous solution was 1:1.2:62. Step B2: Hydroxylated chromium oxide was ultrasonically dispersed in a Tris-HCl buffer solution at pH 7. The ultrasonic frequency was controlled at 25 kHz and the ultrasonic power at 450 W. The mixture was ultrasonicated for 40 min until it was uniformly dispersed. Dopamine hydrochloride and chromium nitrate were added, and the temperature was raised to 60 °C. The mixture was stirred at 630 rpm for 6 h to obtain the modified refining agent. The mass ratio of hydroxylated chromium oxide, Tris-HCl buffer solution, dopamine hydrochloride and chromium nitrate was 2.6:120:1.4:0.4.

[0032] Performance testing The high-strength cemented carbide materials prepared in Examples 1-3 and Comparative Examples 1-4 were subjected to the following performance tests: Preparation of test samples: The high-strength cemented carbide materials prepared in Examples 1-3 and Comparative Examples 1-4 were wire cut and ground to prepare test samples with dimensions of 5.5mm × 6.5mm × 20mm. Bending strength: The bending strength of each test sample was tested according to GB / T 232-2024 using the three-point bending method. Vickers hardness: The room temperature hardness (HV) of each test sample was tested on a Vickers hardness tester under a load of 30 kg; the fracture toughness (KIC) was calculated from the radial crack length generated by the Vickers hardness indentation according to the Nihara formula, in MPa•m. 1 / 2 ; Wear resistance test: The cemented carbide samples prepared in Examples 1-3 and Comparative Examples 1-4 were wire-cut and ground into sample strips with dimensions of 8mm × 12mm × 20mm. The wear rate of each sample strip was measured using a wear testing machine. The test load was 50N, the friction ring speed was 200rpm, and the test time was 2h. The formula for calculating the wear rate is: Wear rate = Volume loss / Test load × Sliding distance Impact resistance: The cemented carbide materials prepared in Examples 1-3 and Comparative Examples 1-4 were wire-cut and ground into specimen strips with dimensions of 5mm×5mm×50mm. The impact strength of each specimen strip was determined by a pendulum impact testing machine in accordance with GB / T 1817-2017. The specific test results are shown in Table 1. Table 1. Performance test results of the cemented carbide materials prepared in Examples 1-3 and Comparative Examples 1-4

[0033] As shown in the table above, compared with Comparative Examples 1-4, the cemented carbide materials prepared in Examples 1-3 have superior hardness, wear resistance and toughness.

[0034] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A high-strength cemented carbide material, characterized in that, The raw materials include the following parts by weight: 5-8 parts cobalt powder, 86-90 parts tungsten carbide powder, 2.4-2.8 parts reinforcing components, and 0.5-0.7 parts modifier and refiner; The reinforcing component is first treated with sulfuric acid solution, then mixed with the thickening component to obtain pretreated cerium oxide, which is then treated with zirconium oxide, tantalum carbide and molybdenum carbide in a mixed acid and stirred to obtain modified cerium oxide, which is finally reacted with a crosslinking agent and tetrabutyl titanate to obtain the final product. The thickening component was prepared by stirring aluminum dihydrogen phosphate solution, silica sol and chromium oxide. The refining agent is first prepared by reacting sodium chromate and sodium acetate to obtain hydroxylated chromium oxide, and then by stirring and treating it with dopamine hydrochloride and vanadium nitrate.

2. The high-strength cemented carbide material according to claim 1, characterized in that, The reinforcing component is prepared by the following steps: Step A1: Add cerium oxide to sulfuric acid solution, stir evenly, add thickening component, heat to 56-60℃, stir reaction for 3.6-4.4h, filter, wash, dry to obtain pretreated cerium oxide; Step A2: Add the pretreated cerium oxide, zirconium oxide, tantalum carbide and molybdenum carbide to the mixed acid, stir evenly, adjust the pH to 8-9, stir for 28-34 min, heat to 92-108℃, stir and react for 2-3 h, cool to room temperature to obtain modified cerium oxide. Step A3: Mix the modified cerium oxide and crosslinking agent evenly, add tetrabutyl titanate and anhydrous ethanol, heat to 50-60℃, stir and react for 3.6-4.2h, wash and dry to obtain the reinforcing component.

3. The high-strength cemented carbide material according to claim 2, characterized in that, In step A1, the mass ratio of cerium oxide, sulfuric acid solution, and thickening component is 2.2-3.4:46-52:4-6.

4. The high-strength cemented carbide material according to claim 2, characterized in that, In step A2, the mass ratio of pretreated cerium oxide, zirconium oxide, tantalum carbide, molybdenum carbide and mixed acid is 1-3:0.04-0.06:0.01-0.03:0.022-0.034:45-55.

5. The high-strength cemented carbide material according to claim 2, characterized in that, In step A3, the mass ratio of modified cerium oxide, crosslinking agent, tetrabutyl titanate and anhydrous ethanol is 3.6-4.8: 2.2-2.6: 0.44-0.52: 20-30.

6. The high-strength cemented carbide material according to claim 1, characterized in that, The thickening component is prepared by the following steps: Aluminum dihydrogen phosphate was added to water to prepare a 50% aluminum dihydrogen phosphate solution, which was then transferred to a high-speed disperser. Silica sol and chromium oxide were added and stirred until homogeneous to obtain the thickening component.

7. The high-strength cemented carbide material according to claim 6, characterized in that, The mass ratio of the aluminum dihydrogen phosphate solution, silica sol, and chromium oxide is 36-40:3.6-4.2:0.02-0.

04.

8. The high-strength cemented carbide material according to claim 1, characterized in that, The refining agent is prepared by the following steps: Step B1: Disperse sodium chromate aqueous solution, sodium acetate solution and polypyrrolidone aqueous solution evenly by ultrasonication. Under nitrogen protection, heat to 210-220℃ and stir for 18-22 hours. Centrifuge, wash the precipitate, and dry to obtain hydroxylated chromium oxide. Step B2: Hydroxylated chromium oxide is ultrasonically dispersed in Tris-HCl buffer, dopamine hydrochloride and vanadium nitrate are added, the temperature is raised to 60-70℃, and the reaction is stirred for 4-6 hours to obtain the modified fine precipitant.

9. A high-strength cemented carbide material according to claim 8, characterized in that, In step B1, the mass ratio of sodium chromate aqueous solution, sodium acetate aqueous solution, and polypyrrolidone aqueous solution is 1:1.2-1.4:62-66. In step B2, the mass ratio of hydroxylated chromium oxide, Tris-HCl buffer, dopamine hydrochloride, and vanadium nitrate is 2.6-3.4:120-160:1.4-1.6:0.4-0.

6.

10. A method for preparing a high-strength cemented carbide material as described in any one of claims 1-9, characterized in that, Includes the following steps: Step S1, Preparation of premix: Cobalt powder, tungsten carbide powder, reinforcing components and modifiers are added to anhydrous ethanol according to the weight parts, ball-milled, dried and sieved to obtain premix; Step S2, spray granulation: The premix prepared in step S1 is spray dried and granulated to obtain granulated premix; Step S3, pressing: The granulated premix obtained in step S2 is pressed into a green body. Step S4, Spark Plasma Sintering: The green blank prepared in step S3 is subjected to plasma sintering to obtain a high-strength cemented carbide material.

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