Hard alloy cutter and preparation method and application thereof

Abstract

The invention relates to the technical field of alloy cutters, and particularly discloses a hard alloy cutter and a preparation method and application thereof. Tungsten carbide powder is used as a main component, HEA alloy powder and cobalt powder are jointly used as a binding phase, and vanadium carbide powder, silicon nitride powder, a reinforcing phase and a modified additive are added as auxiliary components. Under the synergistic effect of the nickel-plated carbon nanotubes, the HEA, the vanadium carbide, the silicon nitride and the modified additive, the grain growth process of silicon carbide can be fully inhibited, a fine grain structure can be kept finally, high strength and hardness and good wear resistance are achieved finally, the strength does not need to be improved by sacrificing the hardness and the wear resistance, and the service life is prolonged. And the defects in the related technology can be effectively overcome.

Description

Technical Field

[0001] The present application relates to the technical field of alloy cutting tools, and more specifically, to a cemented carbide cutting tool and a preparation method and application thereof. Background Art

[0002] Cutting refers to the use of cutting tools to remove excess material from a blank or semi-finished product to create chips, achieving a specified geometric shape, dimensional accuracy, and surface finish. It is the most basic, commonly used, and reliable machining method in machining. Cutting tools are the most critical components of cutting equipment. The properties of the tool material itself, as well as its mechanical and machining properties, are the primary factors influencing actual performance, including cutting efficiency, machining accuracy, workpiece surface finish, and tool life. Carbide tool material is the most promising and competitive tool material in the modern cutting industry. Its excellent overall performance has enabled it to replace most high-speed steel and some superhard material tools in the high-speed cutting field.

[0003] The matrix of cemented carbide is generally one or more hard and refractory metal carbides with a high elastic modulus (usually mainly WC), and the binding phase is a transition metal or other alloy (usually mainly Co or Ni). It is a composite tool prepared by powder metallurgy through molding and sintering. During cutting, the cutting speed of cemented carbide tools can reach 100-300m / min, which is several times the allowable cutting speed of high-speed steel tools, and the service life is several times or even dozens of times longer than that of high-speed steel tools. At present, cemented carbide tools with a series of excellent properties are prepared by adding metal binding phases (such as Co, Ni, etc.) to the WC matrix. They are mainly used in metal cutting, automotive industry, and electronic industry applications.

[0004] Regarding the above-mentioned related technologies, the inventors believe that although tungsten carbide-based cemented carbide tools have better hardness and wear resistance than traditional tools, as more and more new materials are applied to the manufacturing industry, the shortcomings of tungsten carbide tools in strength have gradually become apparent. The improvement of strength often requires sacrificing hardness and wear resistance, which has caused certain limitations on the application of tungsten carbide-based cemented carbide tools. Summary of the Invention

[0005] In the related art, the contradiction between the strength, toughness and wear resistance of tungsten carbide cutting tools is difficult to eliminate, which has caused certain limitations on their application. In order to improve this defect, the present application provides a cemented carbide cutting tool and its preparation method and application.

[0006] In a first aspect, the present application provides a cemented carbide tool, which adopts the following technical solution: A cemented carbide cutting tool comprises the following raw materials in parts by weight: 65-75 parts of tungsten carbide powder, 8-10 parts of HEA alloy powder, 3-5 parts of vanadium carbide powder, 2-4 parts of silicon nitride powder, 0.35-1.15 parts of a reinforcing phase, and 1.5-8 parts of a modifying additive; the reinforcing phase comprises nickel-plated carbon nanotubes, and the modifying additive comprises tungsten-cobalt-titanium alloy particles and zirconium boride.

[0007] By adopting the above-mentioned technical solution, the present application uses tungsten carbide powder as the main component, HEA alloy powder and cobalt powder as a binder phase, and adds vanadium carbide powder, silicon nitride powder, reinforcing phase and modifying additives as auxiliary components. In the raw material system of the present application, the role of tungsten carbide is to provide the main hardness and wear resistance, and HEA serves as a binder phase. Zirconium boride and tungsten-cobalt-titanium alloy particles together serve as hard reinforcing particles and can play a good self-reinforcement role. In addition, zirconium boride can also promote the transformation of boron nitride from α phase to β phase, achieving phase transformation toughening, thereby improving the bending strength of cemented carbide tools. In addition to serving as a binder phase, HEA can also delay the nucleation and growth of new phases through slow diffusion effects and lattice distortion effects; vanadium carbide, as a heterogeneous carbide phase with good ductility, can be deposited at the activation growth site of tungsten carbide grains; silicon nitride, as a ceramic phase, can hinder the growth of tungsten carbide grains through a pinning mechanism; nickel-plated carbon nanotubes can inhibit the movement of new crystal planes of tungsten carbide. Under the synergistic effect of nickel-plated carbon nanotubes, HEA, vanadium carbide, silicon nitride and modified additives, the grain growth process of silicon carbide can be fully suppressed, and ultimately a fine grain structure can be maintained, ultimately achieving higher strength, hardness and better wear resistance without sacrificing hardness and wear resistance to improve strength, which can effectively overcome the defects in related technologies.

[0008] Preferably, the nickel-plated carbon nanotubes are prepared according to the following method: (1) adding carbon nanotubes to a nitric acid solution for oxidation treatment, then washing with deionized water to obtain sensitized carbon nanotubes, mixing the sensitized carbon nanotubes with a tin chloride solution and reacting to obtain surface-deposited carbon nanotubes, and treating the surface-deposited carbon nanotubes with a palladium chloride solution and a boric acid solution to obtain pretreated carbon nanotubes; (2) adding the pretreated carbon nanotubes to a chemical nickel plating solution, washing with deionized water after nickel plating, separating by centrifugation and filtration, and drying the obtained solid to obtain nickel-plated carbon nanotubes.

[0009] By adopting the above technical solution, the present application first uses nitric acid to oxidize carbon nanotubes, causing polar groups such as carboxyl groups to form on the surface of the carbon nanotubes, thereby obtaining sensitized carbon nanotubes. After the sensitized carbon nanotubes are mixed with a tin chloride solution, the tin chloride hydrolyzes on the surface of the sensitized carbon nanotubes, producing basic tin chloride nanoprecipitates. These precipitates are loosely adsorbed on the surface of the sensitized carbon nanotubes. The divalent palladium is then reduced to nanoscale palladium in a palladium chloride solution, resulting in pretreated carbon nanotubes with palladium atoms on the surface. In an electroless nickel plating solution, the monovalent nickel can be reduced to a single substance under the catalysis of palladium, thereby forming a nickel coating on the surface of the carbon nanotubes, thereby obtaining nickel-plated carbon nanotubes.

[0010] Preferably, in step (2) of preparing the nickel-plated carbon nanotubes, the nickel plating treatment is carried out at 20-25°C.

[0011] By adopting the above technical solution, the present application optimizes the temperature range of nickel plating treatment. Within this range, the nickel plating reaction can proceed smoothly, the obtained coating is denser, and the grain growth of tungsten carbide can be more effectively hindered through synergistic effects.

[0012] Preferably, in the step (2) of preparing the nickel-plated carbon nanotubes, the nickel plating treatment time is 70-90 minutes.

[0013] By adopting the above technical solution, the present application optimizes the time range of nickel plating treatment. Within this range, the nickel plating reaction can be fully carried out, the obtained coating is denser, and the grain growth of tungsten carbide can be more effectively hindered through synergistic effects.

[0014] Preferably, the reinforcement phase further includes silicon carbide whiskers.

[0015] By adopting the above technical solution, silicon carbide whiskers can improve the strength of carbide tools through two mechanisms: whisker bridging and whisker extraction, and can slow down the wear of the tools, helping to extend the service life of the alloy tools.

[0016] Preferably, the modifying additive further includes at least one of chromium carbide and tantalum carbide.

[0017] By adopting the above technical solution, chromium carbide can block contact between tungsten carbide grains at the tungsten carbide grain boundaries, while tantalum carbide can be adsorbed on the surface of tungsten carbide, reducing its surface energy. At the same time, both can also reduce the solubility of tungsten carbide in the binder phase. Because the binder phase of this application already has a certain effect of hindering grain growth, the addition of chromium carbide and tantalum carbide can produce a synergistic effect, thereby fully inhibiting grain growth and helping to improve the strength, hardness and wear resistance of alloy tools.

[0018] Preferably, the modifying additive further includes at least one of rhenium and ruthenium.

[0019] By adopting the above technical solution, the addition of rhenium and ruthenium can enhance the isotropy of tungsten carbide grains and reduce the average particle size of tungsten carbide, thereby achieving a fine grain strengthening effect. In addition, the components of the present application can synergistically hinder the growth of the replaced grains, thereby effectively improving the strength, hardness and wear resistance of the alloy tool.

[0020] Preferably, the modifying additive further includes at least one of indium and cerium.

[0021] By adopting the above technical solution, indium and cerium can synergistically promote grain refinement with rhenium, ruthenium, chromium carbide and tantalum carbide, which helps to fully improve the strength, hardness and wear resistance of alloy tools.

[0022] In a second aspect, the present application provides a method for preparing a cemented carbide tool, which adopts the following technical solution.

[0023] A method for preparing a cemented carbide tool comprises the following steps: (1) Weigh tungsten carbide powder, HEA alloy powder, cobalt powder, molybdenum carbide powder, vanadium carbide powder, silicon nitride powder, reinforcing phase and modifying additives and set aside; (2) mixing tungsten carbide powder, HEA alloy powder, cobalt powder, molybdenum carbide powder, vanadium carbide powder and silicon nitride powder, ball milling and drying, pressing and molding in a mold to obtain a green body, sintering the green body under nitrogen, grinding and sieving to obtain an intermediate product; (3) The intermediate product is mixed with the reinforcing phase and the improved additive, dried, pressed into a mold, and microwave sintered under argon to obtain a cemented carbide tool.

[0024] By adopting the above technical solution, the present application first mixes the raw materials except the reinforcing phase and the improved additives and then performs compression sintering, and then adds the reinforcing phase and the improved additives. After compression molding and microwave sintering, a cemented carbide tool with good strength, hardness and wear resistance is obtained.

[0025] In a third aspect, the present application provides an application of a cemented carbide tool, which adopts the following technical solution.

[0026] An application of a cemented carbide tool comprises applying the cemented carbide tool to cutting processing of metal materials.

[0027] By adopting the above technical solution, the cemented carbide tool of the present application has good hardness, strength and wear resistance. It is not only suitable for cutting processing of ordinary metal materials, but also can adapt to the stringent requirements of high-end manufacturing industry for cutting tools.

[0028] In summary, this application has the following beneficial effects: 1. This application utilizes tungsten carbide powder as the primary component, HEA alloy powder and cobalt powder as a binder phase, and adds vanadium carbide powder, silicon nitride powder, a reinforcing phase, and a modifying additive as auxiliary components. The synergistic effects of nickel-plated carbon nanotubes, HEA, vanadium carbide, silicon nitride, and the modifying additives effectively suppress the grain growth of silicon carbide, ultimately maintaining a fine grain structure. Ultimately, this invention simultaneously achieves high strength, hardness, and good wear resistance without sacrificing hardness and wear resistance to improve strength, effectively overcoming the shortcomings of related technologies.

[0029] 2. In this application, chromium carbide and tantalum carbide are preferred as modifying additives. Chromium carbide can block contact between tungsten carbide grains at the tungsten carbide grain boundaries, while tantalum carbide can be adsorbed on the surface of tungsten carbide, reducing its surface energy. Both can also reduce the solubility of tungsten carbide in the binder phase. Since the binder phase of this application already has a certain effect of hindering grain growth, the addition of chromium carbide and tantalum carbide can produce a synergistic effect, thereby fully inhibiting grain growth and helping to improve the strength, hardness, and wear resistance of the alloy tool. DETAILED DESCRIPTION

[0030] The present application is further described in detail below with reference to the Examples, Preparation Examples and Comparative Examples. The raw materials involved in the present application can all be obtained commercially.

[0031] Preparation example of nickel-plated carbon nanotubes The following is an explanation using Preparation Example 1.

[0032] Preparation Example 1 In this preparation example, the average diameter of the carbon nanotubes is 40 nm and the average length is 6.5 μm; the concentrations of the components in the chemical nickel plating solution are as follows: 0.11 mol / L nickel sulfate, 0.17 mol / L sodium citrate, 0.2 mol / L ammonium sulfate, 0.36 mol / L sodium dihydrogen phosphate, and 0.1 g / L sodium octadecylbenzenesulfonate.

[0033] In this preparation example, nickel-plated carbon nanotubes were prepared according to the following method: (1) adding carbon nanotubes to a 68 wt % nitric acid solution at a weight ratio of 1:100 for oxidation treatment, first ultrasonically dispersing for 45 min, then heating in an oil bath at 140° C. for 2.5 h, and finally washing with deionized water to obtain sensitized carbon nanotubes, mixing the sensitized carbon nanotubes with a 10 g / L tin chloride solution at a weight ratio of 1:50 and reacting to obtain surface-deposited carbon nanotubes, using a 0.5 g / L palladium chloride solution and a 10 g / L boric acid solution to treat the surface-deposited carbon nanotubes, and then taking out and drying to obtain pretreated carbon nanotubes; (2) Pretreated carbon nanotubes were added to a chemical nickel plating solution at a dosage of 2 g / L, and after nickel plating at 35° C. for 45 min, the pretreated carbon nanotubes were washed with deionized water, separated by centrifugation and filtration, and the obtained solid was dried to obtain nickel-plated carbon nanotubes.

[0034] As shown in Table 1, the difference between Preparation Examples 1-7 is that the temperature and time of the nickel plating treatment are different.

[0035] Table 1 Parameters of nickel plating treatment sample Nickel plating temperature / ℃ Nickel plating time Preparation Example 1 35 45 Preparation Example 2 25 45 Preparation Example 3 22 45 Preparation Example 4 20 45 Preparation Example 5 20 70 Preparation Example 6 20 80 Preparation Example 7 20 90 Example

[0036] Examples 1-3 The following description will be made using Example 1 as an example.

[0037] Example 1 In this embodiment, the average particle size of the tungsten carbide powder is 2.5 μm, and the HEA alloy powder is AlCo alloy with an average particle size of 25 μm. 0.4 CrFeNi 2.7 The average particle size of the vanadium carbide powder is 8 μm, and the average particle size of the silicon nitride powder is 0.8 μm; the reinforcing phase is the nickel-plated carbon nanotubes of Preparation Example 1, and the modified additives are composed of 1.2 kg of tungsten-cobalt-titanium alloy particles and 0.3 kg of zirconium boride. The tungsten-cobalt-titanium alloy particles contain 6.5 wt% of cobalt and 22 wt% of titanium carbide, and the remainder is tungsten carbide. The average particle size of the tungsten-cobalt-titanium alloy particles is 0.6 mm, and the average particle size of the zirconium boride is 0.2 μm.

[0038] This embodiment provides a cemented carbide tool, including the following raw materials: 65 kg of tungsten carbide powder, 8 kg of HEA alloy powder, 3 kg of vanadium carbide powder, 2 kg of silicon nitride powder, 0.35 kg of reinforcing phase, and 1.5 kg of modifying additives.

[0039] This embodiment provides a method for preparing a cemented carbide tool, comprising the following steps: (1) Weigh tungsten carbide powder, HEA alloy powder, cobalt powder, molybdenum carbide powder, vanadium carbide powder, silicon nitride powder, reinforcing phase and modifying additives and set aside; (2) Tungsten carbide powder, HEA alloy powder, cobalt powder, molybdenum carbide powder, vanadium carbide powder and silicon nitride powder were mixed, stirred at a rate of 300 rpm for 20 min, and then ball-milled at a rate of 200 rpm for 16 h. During ball milling, the ball-to-liquid mass ratio was controlled to be 10:2:1. Zirconia balls were selected and anhydrous ethanol was selected as the dispersion medium. After ball milling, the mixture was dried at 70 ° C for 3 h, pressed in a mold, and the molding pressure was controlled to be 10 MPa to obtain a green body. The green body was sintered under nitrogen, heated to 500 ° C at a heating rate of 8 ° C / min, and kept warm for 45 min; then heated to 800 ° C at a heating rate of 5 ° C / min, and kept warm for 2 h; then heated to 1000 ° C at a heating rate of 3 ° C / min, and kept warm for 1 h. Then, the mixture was cooled to room temperature at a rate of 2 ° C / min, and ground through a 3000 mesh sieve to obtain an intermediate product. (3) The intermediate product was mixed with the reinforcing phase and the improved additive, stirred at a rate of 600 rpm for 15 min, dried at 70 °C for 3 h, and then pressed into shape in a mold at a pressure of 10 MPa. Microwave sintering was performed under argon, and the temperature was increased to 800 °C at a heating rate of 50 °C / min, and kept at this temperature for 30 min, with the microwave power controlled at 3 kW and the frequency controlled at 2.45 GHz; the temperature was increased to 1350 °C at a heating rate of 10 °C / min, and kept at this temperature for 40 min, with the microwave power controlled at 1 kW and the frequency controlled at 2.45 GHz; and finally cooled in the furnace to obtain a cemented carbide tool.

[0040] This embodiment also provides an application of a cemented carbide tool, including applying the cemented carbide tool to cutting processing of metal materials.

[0041] As shown in Table 2, the main difference between Examples 1-3 is that the raw material ratios of the cemented carbide cutting tools are different.

[0042] Table 2 Raw material ratio of cemented carbide tools As shown in Table 3, the difference between Example 1 and Examples 4-9 is that the preparation examples of nickel-plated carbon nanotubes are different.

[0043] Table 3 Preparation example of nickel-plated carbon nanotubes Example 10 The difference between this embodiment and embodiment 9 is that the reinforcement phase further includes silicon carbide whiskers, the average diameter of the silicon carbide whiskers is 0.5 μm, the average length is 20 μm, and the amount of silicon carbide whiskers used is 0.80 kg.

[0044] Example 11 The difference between this embodiment and embodiment 10 is that the modifying additive further includes 2.5 kg of chromium carbide.

[0045] Example 12 The difference between this embodiment and embodiment 11 is that the modifying additive further includes 2 kg of tantalum carbide.

[0046] Example 13 The difference between this embodiment and embodiment 12 is that the modifying additive further includes 0.3 kg of rhenium powder.

[0047] Example 14 The difference between this embodiment and embodiment 13 is that the modifying additive further includes 0.7 kg of ruthenium powder.

[0048] Example 15 The difference between this embodiment and embodiment 14 is that the modifying additive further includes 0.8 kg of indium powder.

[0049] Example 16 The difference between this embodiment and embodiment 15 is that the modifying additive further includes 0.2 kg of cerium powder.

[0050] Comparative Example Comparative Example 1 This comparative example provides a cemented carbide tool comprising the following raw materials: 60kg tungsten carbide powder, 8kg nickel powder, 5kg molybdenum carbide powder, 2kg silicon nitride powder, 6kg strengthening phase, and 4kg improved additives.

[0051] The reinforcement phase was prepared by the following method: Cobalt nitrate and yttrium nitrate are dispersed in deionized water, stirred at 200 rpm for 10 minutes, a complexing agent is added, heated to 60°C, stirred at 100 rpm for 30 minutes, citric acid is added, heated to 80°C, stirred at 150 rpm for 5 hours, dried at 100°C for 12 hours, and then heat-treated by heating to 300°C at 2°C / min, keeping warm for 2 hours, then heating to 600°C at 5°C / min, keeping warm for 3 hours, naturally cooling, grinding, and passing through a 1000-mesh sieve to obtain a reinforcing phase; in parts by mass, the weight ratio of cobalt nitrate, yttrium nitrate, deionized water, complexing agent, and citric acid is 20:8:70:1:10.

[0052] The complexing agent used in preparing the reinforcing phase is prepared by the following method: (1) Dispersing tartaric acid in dichloromethane, stirring at 100 rpm for 15 minutes, adding copper sulfate and p-toluenesulfonyl chloride, stirring for 3 minutes, controlling the temperature to 4°C, stirring at 150 rpm for 4 hours, then heating to 25°C, stirring at 80 rpm for 10 hours, centrifuging at 3000 rpm for 5 minutes, and vacuum drying at 60°C for 12 hours to obtain sulfonylated tartaric acid; in parts by mass, the weight ratio of tartaric acid, p-toluenesulfonyl chloride, copper sulfate, and dichloromethane is 15:8:0.2:70; (2) Dispersing sulfonylated tartaric acid in deionized water, adding graphene oxide and 1-ethyl-(3-dimethylaminopropyl)carbodiimide, ultrasonically dispersing at 30 kHz for 25 minutes, adjusting the pH to 5.5, heating to 60°C, stirring at 100 rpm for 4 hours, filtering, and freeze-drying at -50°C for 12 hours to obtain a complexing agent; wherein the weight ratio of sulfonylated tartaric acid, graphene oxide, deionized water, and 1-ethyl-(3-dimethylaminopropyl)carbodiimide is 5:2:60:0.1.

[0053] The improved additive is prepared by the following method: (1) adding chromium formate and aluminum nitrate to deionized water, stirring at 100 rpm for 10 min, adding ferric nitrate, stirring at 100 rpm for 15 min, then adding boric acid, adjusting the pH to 3, to obtain a mixed salt solution; wherein the weight ratio of chromium formate, aluminum nitrate, ferric nitrate, boric acid, and deionized water is 3:5:15:0.5:120; (2) Sodium alginate was dispersed in deionized water, heated to 30°C, stirred at 80 rpm for 8 minutes, and calcium chloride was added and stirred for 5 minutes to obtain a sol; wherein the weight ratio of sodium alginate, calcium chloride, and deionized water was 2:4:60; (3) adding the sol to the mixed salt solution, stirring at 100 rpm for 20 min, freeze-drying at -50 ° C for 24 h, pre-calcining, heating to 300 ° C at a heating rate of 8 ° C / min, keeping warm for 2 h, then heating to 700 ° C at a heating rate of 5 ° C / min, keeping warm for 1 h; cooling to room temperature to obtain a composite oxide; microwave sintering the composite oxide at a heating rate of 10 ° C / min, 2.45 GHz, 1200 ° C for 30 min, controlling the microwave power to 1.5 KW, cooling to room temperature to obtain an intermediate, adding the intermediate to the etching solution, soaking for 5 min, drying at 80 ° C for 4 h, grinding through a 3000 mesh sieve to obtain an improved additive; wherein the mass ratio of the sol to the mixed salt solution is 30:60; the mass ratio of the intermediate to the etching solution is 15:25; the etching solution is prepared by mixing nitric acid and hydrofluoric acid in a mass ratio of 3:0.4.

[0054] Comparative Example 2 The difference between this comparative example and Example 1 is that the HEA alloy powder is replaced with nickel powder of the same weight.

[0055] Comparative Example 3 The difference between this comparative example and Example 1 is that the raw material components of the cemented carbide cutting tool do not include vanadium carbide powder.

[0056] Comparative Example 4 The difference between this comparative example and Example 1 is that the raw material components of the cemented carbide cutting tool do not include silicon nitride powder.

[0057] Comparative Example 5 The difference between this comparative example and Example 1 is that the raw material composition of the cemented carbide tool does not include a reinforcing phase.

[0058] Comparative Example 6 This comparative example is different from Example 1 in that the modifying additive does not include tungsten-cobalt-titanium alloy particles.

[0059] Comparative Example 7 This comparative example differs from Example 1 in that the modifying additive does not include zirconium boride.

[0060] Performance testing methods The thickness of the carbide tool was controlled to be 5.5 mm, and the carbide tool was tested as follows (see Table 4 for the test results): (1) Tested according to GB / T232-2010, using the three-point bending method to test the bending strength; (2) The prepared cemented carbide tool was used as a cutting tool to cut 42CrMo steel at a cutting speed of 250 m / min, a cutting amount of 2 mm, and a feed rate of 0.1 mm / rev. The processing length completed when the cutting tool wear reached 0.1 mm was used as the evaluation standard. The unit was m. The larger the processing length value, the better the wear resistance of the cemented carbide. (3) Test the room temperature hardness (HV) on a Vickers hardness tester with a load of 30 kg and a unit of GPa.

[0061] Table 4 Test results Combining Examples 1-3 and Comparative Example 1 and Table 4, it can be seen that the bending strength, wear resistance and hardness of Example 1 are better than those of Comparative Example 1. This is because under the synergistic effect of nickel-plated carbon nanotubes, HEA, vanadium carbide, silicon nitride and modifying additives, the grain growth process of silicon carbide can be fully suppressed, and ultimately a fine grain structure can be maintained, and the strength and toughness are improved. Ultimately, it has higher strength, hardness and better wear resistance at the same time without sacrificing hardness and wear resistance to improve strength, which can effectively overcome the defects in the related art.

[0062] Comparing Example 1 and Comparative Example 2, as shown in Table 4, shows that Example 1 exhibits superior flexural strength, wear resistance, and hardness to Comparative Example 2. This is due to the lack of the HEA alloy as a binder phase in Comparative Example 2. In addition to serving as a binder phase, HEA also slows the nucleation and growth of new phases through slow diffusion and lattice distortion. Without this effect, Comparative Example 2 is unable to effectively suppress tungsten carbide grain growth, resulting in inferior overall performance.

[0063] Combining Example 1 with Comparative Example 3 and Table 4, it can be seen that Example 1 exhibits superior flexural strength, wear resistance, and hardness to Comparative Example 3. This is due to the lack of vanadium carbide powder in Comparative Example 3. Vanadium carbide, as a heterogeneous carbide phase with excellent ductility, can deposit at the activated growth sites of tungsten carbide grains, providing a synergistic inhibitory effect on grain growth. Without this inhibitory effect, Comparative Example 3 is unable to effectively inhibit tungsten carbide grain growth, resulting in inferior performance across all aspects.

[0064] Combining Example 1 with Comparative Example 4 and Table 4, it can be seen that Example 1 exhibits superior flexural strength, wear resistance, and hardness to Comparative Example 4. This is because Comparative Example 4 lacks silicon nitride powder. As a ceramic phase, silicon nitride can synergize with other components through a pinning mechanism, thereby inhibiting tungsten carbide grain growth. Without this mechanism, Comparative Example 3 was unable to effectively inhibit tungsten carbide grain growth, resulting in inferior performance across all aspects.

[0065] Comparing Example 1 and Comparative Example 5 with Table 4 shows that Example 1 exhibits superior flexural strength, wear resistance, and hardness to Comparative Example 5. This is due to the lack of a reinforcing phase in Comparative Example 5. The nickel-plated carbon nanotubes, acting as a reinforcing phase, inhibit the movement of newly formed tungsten carbide crystal planes, providing a synergistic inhibitory effect on grain growth. Without this reinforcement, Comparative Example 5 would be unable to effectively inhibit tungsten carbide grain growth, resulting in inferior overall performance.

[0066] Combining Example 1 with Comparative Examples 6-7 and Table 4, it can be seen that Example 1 exhibits superior flexural strength, wear resistance, and hardness to Comparative Examples 6-7. This is due to the lack of tungsten-cobalt-titanium alloy particles in Comparative Example 6 and the lack of zirconium boride in Comparative Example 7. Zirconium boride and tungsten-cobalt-titanium alloy particles, acting together as hard reinforcing particles, can exert a strong self-reinforcement effect. Furthermore, zirconium boride can promote the transformation of boron nitride from the α phase to the β phase, achieving phase transformation toughening and thus improving the flexural strength of the cemented carbide tool. In the absence of these two modifying additives, the strength, hardness, and wear resistance of Comparative Examples 6-7 are all affected, resulting in poor overall performance.

[0067] From Example 1 and Examples 4-9 and Table 4, it can be seen that in the method for preparing nickel-plated carbon nanotubes, as the nickel plating temperature decreases and the nickel plating time is extended, the nickel plating reaction can proceed more smoothly, so that the coatings obtained in Examples 4-9 are denser and can more effectively hinder the grain growth of tungsten carbide through synergistic effects, thereby improving the performance of cemented carbide tools.

[0068] Combining Example 9 and Example 10 with Table 4, it can be seen that Example 10 has better bending strength, wear resistance and hardness. This is because silicon carbide whiskers can improve the strength of cemented carbide tools through two mechanisms: whisker bridging and whisker pulling out, and can slow down the wear of the tool, thereby helping to extend the service life of the alloy tool.

[0069] Combining Example 10, Examples 11-12, and Table 4, it can be seen that the bending strength, wear resistance, and hardness of Examples 10-12 improve in sequence. This is because chromium carbide can block contact between tungsten carbide grains at the tungsten carbide grain boundaries, while tantalum carbide can adsorb on the surface of tungsten carbide, reducing its surface energy. At the same time, both can also reduce the solubility of tungsten carbide in the binder phase. Since the binder phase of this application already has a certain effect of hindering grain growth, the addition of chromium carbide and tantalum carbide can produce a synergistic effect, thereby fully inhibiting grain growth and helping to improve the strength, hardness, and wear resistance of the alloy tool.

[0070] Combining Examples 12, 13-14, and Table 4, it can be seen that the bending strength, wear resistance, and hardness of Examples 12-14 improve in this order. This is because the addition of rhenium and ruthenium can enhance the isotropy of tungsten carbide grains and reduce the average particle size of tungsten carbide, thereby playing a role in grain refinement. In addition, the components of the present application can synergistically hinder the growth of the replaced grains, thereby effectively improving the strength, hardness, and wear resistance of the alloy tool.

[0071] From Example 14, Examples 15-16 and Table 4, it can be seen that the bending strength, wear resistance and hardness of Examples 15-16 are improved in sequence. This is because indium and cerium can synergistically promote grain refinement with rhenium, ruthenium, chromium carbide and tantalum carbide, which helps to fully improve the strength, hardness and wear resistance of the alloy tool.

[0072] The above embodiments are merely explanations of the present application and are not limitations of the present application. After reading this specification, those skilled in the art may make modifications to the embodiments of the present application as needed without any creative contribution. However, as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A cemented carbide tool, characterized in that: The cutting tool comprises the following raw materials in parts by weight: 65-75 parts of tungsten carbide powder, 8-10 parts of HEA alloy powder, 3-5 parts of vanadium carbide powder, 2-4 parts of silicon nitride powder, 0.35-1.15 parts of reinforcing phase, and 1.5-8 parts of modifying additives; the reinforcing phase comprises nickel-plated carbon nanotubes, and the modifying additives comprise tungsten-cobalt-titanium alloy particles and zirconium boride.

2. The cemented carbide tool according to claim 1, characterized in that The nickel-plated carbon nanotubes are prepared according to the following method: (1) adding carbon nanotubes to a nitric acid solution for oxidation treatment, then washing with deionized water to obtain sensitized carbon nanotubes, mixing the sensitized carbon nanotubes with a tin chloride solution and reacting them to obtain surface-deposited carbon nanotubes, and treating the surface-deposited carbon nanotubes with a palladium chloride solution and a boric acid solution to obtain pretreated carbon nanotubes; (2) The pretreated carbon nanotubes are added to a chemical nickel plating solution, washed with deionized water after nickel plating, and then separated by centrifugation and filtration. The obtained solid is then dried to obtain nickel-plated carbon nanotubes.

3. The cemented carbide tool according to claim 2, characterized in that In the step (2) of preparing the nickel-plated carbon nanotubes, the nickel plating treatment is carried out at 20-25°C.

4. The cemented carbide tool according to claim 2, characterized in that In the step (2) of preparing the nickel-plated carbon nanotubes, the nickel plating treatment time is 70-90 minutes.

5. The cemented carbide tool according to claim 1, wherein The reinforcement phase also includes silicon carbide whiskers.

6. The cemented carbide tool according to claim 1, characterized in that The modifying additive further comprises at least one of chromium carbide and tantalum carbide.

7. The cemented carbide tool according to claim 6, characterized in that: The modifying additive further includes at least one of rhenium and ruthenium.

8. The cemented carbide tool according to claim 7, characterized in that: The modifying additive further comprises at least one of indium and cerium.

9. The method for preparing a cemented carbide tool according to any one of claims 1 to 8, characterized in that: The following steps are involved: (1) Weigh tungsten carbide powder, HEA alloy powder, cobalt powder, molybdenum carbide powder, vanadium carbide powder, silicon nitride powder, reinforcing phase and modifying additives and set aside; (2) Tungsten carbide powder, HEA alloy powder, cobalt powder, molybdenum carbide powder, vanadium carbide powder and silicon nitride powder are mixed and stirred, ball milled and dried, pressed in a mold to obtain a green body, sintered the green body under nitrogen, ground and sieved to obtain an intermediate product; (3) The intermediate product is mixed with the reinforcing phase and the improved additive, dried, pressed into a mold, and microwave sintered under argon to obtain a cemented carbide tool.

10. Use of the cemented carbide tool according to any one of claims 1 to 8, characterized in that: The method comprises applying the cemented carbide tool to cutting processing of metal materials.

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