A high-damping, vibration-reducing superhard cutting tool and its preparation method

Abstract

This invention provides a high-damping, vibration-reducing superhard cutting tool and its preparation method. The high-damping, vibration-reducing cutting tool includes: a tool tip, which is made of polycrystalline cubic boron nitride; a substrate layer, which is made of cemented carbide; and an alloy layer, which is a titanium alloy, disposed between the tool tip and the substrate layer. The titanium alloy comprises: titanium, 65%-75%; niobium, 12%-20%; molybdenum, 5%-7%; vanadium, 5%-15%; iron, 2.5%-5%; chromium, 4.5%-8.5%; and aluminum, 1%-2%. By placing the alloy layer between the tool tip and the substrate layer, this invention improves the damping performance of the high-damping, vibration-reducing superhard cutting tool, which not only improves the quality of the machined surface and the efficiency of hard turning, but also reduces the vibration generated during cutting. The combination of the tool tip, substrate layer, and alloy layer reduces chatter generated by the high-damping, vibration-reducing superhard cutting tool during cutting operations, thereby increasing the tool's service life.

Description

Technical Field

[0001] This invention relates to the field of superhard materials technology, and more specifically, to a high-damping, vibration-reducing superhard cutting tool and its preparation method. Background Technology

[0002] Cubic boron nitride (cBN) is the second type of superhard material obtained using ultra-high pressure and high temperature technology after synthetic diamond. Polycrystalline cubic boron nitride (PcBN) can be produced by high-temperature and high-pressure sintering of cubic boron nitride and binder under high temperature and high pressure conditions. Its mechanical and thermal properties are affected by the type and content of binder. The higher the content of cubic boron nitride, the higher the hardness of polycrystalline cubic boron nitride, but the corresponding toughness is generally worse.

[0003] Superhard cutting tools, as the most advantageous tool material for machining high-hardness and difficult-to-machine ferrous metals, are essential tools for precision and ultra-precision turning. Brazed cutting tools are made by brazing polycrystalline cubic boron nitride (cBN) and a cemented carbide matrix. In existing technologies, PcBN tools with lower cBN content are often used when cutting materials with uneven hardness or containing high-hardness phases, as well as in interrupted machining, to improve the tool's toughness and impact resistance. However, when the cBN content is low, the tool's hardness and wear resistance decrease, thus affecting its lifespan.

[0004] Therefore, how to improve the toughness of cutting tools while ensuring their hardness is an urgent problem to be solved. Summary of the Invention

[0005] The present invention aims to provide a high-damping superhard cutting tool and its preparation method. By adding a high-damping alloy layer between the cutting tip and the substrate layer, the damping performance of the high-damping superhard cutting tool is improved, the vibration of the high-damping superhard cutting tool is reduced, and the service life of the high-damping superhard cutting tool is guaranteed.

[0006] To achieve the above objectives, the present invention provides a high-damping, vibration-reducing superhard cutting tool, comprising: a cutting tip, the cutting tip being polycrystalline cubic boron nitride; a substrate layer, the substrate layer being cemented carbide; and an alloy layer, the alloy layer being a titanium alloy, the alloy layer being disposed between the cutting tip and the substrate layer; wherein the titanium alloy comprises: titanium, 65%-75%; niobium, 12%-20%; molybdenum, 5%-7%; vanadium, 5%-15%; iron, 2.5%-5%; chromium, 4.5%-8.5%; and aluminum, 1%-2%.

[0007] This invention provides a high-damping, vibration-reducing superhard cutting tool. By placing an alloy layer between the tool tip and the substrate layer, the damping performance of the high-damping, vibration-reducing superhard cutting tool is improved. This not only enhances the quality of the machined surface and the efficiency of hard turning but also reduces vibrations generated during cutting. Using polycrystalline cubic boron nitride as the tool tip material ensures that the high-damping, vibration-reducing superhard cutting tool possesses characteristics such as high hardness, high thermal stability, good chemical stability, and good weldability, guaranteeing the overall performance of the high-damping, vibration-reducing superhard cutting tool. Using cemented carbide as the substrate layer material ensures that the high-damping, vibration-reducing superhard cutting tool has high hardness, toughness, and thermal conductivity.

[0008] The titanium alloy comprises: titanium (65%-75%), niobium (12%-20%), molybdenum (5%-7%), vanadium (5%-15%), iron (2.5%-5%), chromium (4.5%-8.5%), and aluminum (1%-2%). The titanium alloy contains a significant amount of β-stabilizing elements, such as niobium, molybdenum, vanadium, iron, and chromium. During rapid cooling after welding, these elements ensure that the β phase in the titanium alloy does not transform into the α phase, or only a small amount transforms, thus guaranteeing the damping performance of the titanium alloy. Furthermore, aluminum serves as a strengthening element. The proportions of each component in the titanium alloy ensure its good damping properties, thereby guaranteeing the vibration reduction performance of the high-damping, vibration-damping superhard cutting tool. The combination of the tool tip, the substrate layer, and the alloy layer reduces chatter generated by the high-damping, vibration-damping superhard cutting tool during cutting operations and also reduces the surface roughness of the workpiece after machining.

[0009] In any of the above technical solutions, the thickness of the titanium alloy accounts for 30%-40% of the thickness of the high-damping, vibration-reducing superhard cutting tool.

[0010] By placing and connecting the titanium alloy between the cutting head and the substrate layer, the resulting high-damping superhard cutting tool exhibits high damping performance. Excessive titanium alloy thickness compromises the overall performance of the high-damping superhard cutting tool, while insufficient thickness results in poor vibration damping. By setting the titanium alloy thickness to 30%-40% of the total cutting tool thickness, this ratio ensures both high hardness and high toughness while maintaining optimal high damping performance, thus improving the vibration damping capacity of the high-damping superhard cutting tool.

[0011] In any of the above technical solutions, the surface roughness of the titanium alloy is 3μm-12μm.

[0012] The titanium alloy has a certain surface roughness to ensure high stability of the connection between the tool tip and the base layer and the alloy layer, thus preventing the high-damping, vibration-reducing superhard tool from splitting during cutting operations. The surface roughness of the titanium alloy is 3μm-12μm.

[0013] In any of the above technical solutions, silver powder and copper powder are provided between the cutting head and the alloy layer; and / or copper powder is provided between the alloy layer and the substrate layer.

[0014] By placing silver and copper powder between the cutting tip and the alloy layer, a strong connection is achieved. During the welding process, silver, with its low melting point, melts first. Therefore, under the same heating conditions, silver increases the diffusion efficiency of the active element titanium in the alloy layer between the alloy layer and the cutting tip. The cutting tip, being relatively stable, combines with the active titanium in the alloy layer to form a high-strength joint. Similarly, by placing copper powder between the alloy layer and the substrate layer, a strong connection is achieved. Because copper has a high melting point, and both the alloy layer and the substrate layer are alloy materials, a high-strength joint can be obtained without the need for titanium in the alloy layer to diffuse into the substrate layer.

[0015] In any of the above technical solutions, the particle size of the silver powder is less than 200 mesh; and / or the particle size of the copper powder is less than 200 mesh.

[0016] If the particle size of the metal powder is too small, it can easily cause excessive solder extrusion and uneven weld gap when applied to the weld, which will adversely affect the wear and service life of the high-damping and vibration-damping superhard tool. If the particle size of the metal powder is too large, it will cause problems such as insufficient alloying between powders and reduced welding strength. Therefore, the particle size range of the metal powder is selected to be less than 200 mesh to ensure the welding quality of the high-damping and vibration-damping superhard tool.

[0017] In any of the above technical solutions, the mass ratio of silver powder to copper powder between the cutting head and the alloy layer is 1:3-1:2.

[0018] Silver powder and copper powder are placed between the cutter head and the alloy layer, and the content of copper powder is controlled to be greater than that of silver powder. On the one hand, silver powder melts first due to its lower melting point, thereby improving the diffusion efficiency of the active element titanium in the alloy layer between the cutter head and the alloy layer. On the other hand, copper powder has the advantage of lower cost.

[0019] This invention provides a method for preparing a high-damping, vibration-damping superhard cutting tool. The method, used to prepare the high-damping, vibration-damping superhard cutting tool as described above, includes the following steps: sequentially assembling a cutting head, an alloy layer, and a substrate layer to obtain an assembly; heating the assembly at a rate of 8°C / min-10°C / min to 900°C-1000°C and holding it at that temperature for 30-60 minutes to obtain a cutting tool assembly; cooling the cutting tool assembly by first cooling it at a rate of 5°C / min-10°C / min to 750°C-800°C, then cooling it at a rate of 40°C / min-60°C / min to 200°C-250°C and holding it at that temperature for 30 minutes, and finally cooling it at a rate of 5°C / min-10°C / min to room temperature to obtain the high-damping, vibration-damping superhard cutting tool.

[0020] The present invention provides a method for preparing a high-damping, vibration-reducing superhard cutting tool. The tool tip, alloy layer, and substrate layer are assembled sequentially to obtain an assembly. The alloy layer is positioned in the middle layer, giving the high-damping, vibration-reducing superhard cutting tool high damping performance, thereby reducing chatter. The assembly is then heated to weld its components together. First, the temperature is increased to 900℃-1000℃ at a rate of 8℃ / min-10℃ / min and held for 30min-60min. Under these conditions, the tool tip and... The alloy layers are interconnected with each other and with the substrate layer to form a tool assembly. The high-temperature tool assembly is then cooled at a low speed, then a high speed, and finally a low speed. Specifically, it is first cooled to 750°C-800°C at a rate of 5°C / min-10°C / min, then cooled to 200°C-250°C at a rate of 40°C / min-60°C / min, held at that temperature for 30 minutes, and finally cooled to room temperature at a rate of 5°C / min-10°C / min. This process yields the high-damping, vibration-reducing superhard tool of this embodiment.

[0021] For welding, the slower the cooling rate, the lower the residual stress. By cooling at a slow rate, the high-damping superhard tool will not generate residual stress due to rapid cooling, thus avoiding cracks or fractures and ensuring its high hardness and toughness. However, titanium alloys contain a large number of β-phase stabilizing elements. To prevent the β-phase from transforming into the α-phase, the cooling rate needs to be as fast as possible. Therefore, when the temperature drops to 750℃-800℃ during welding, rapid cooling is required to ensure that the β-phase in the titanium alloy does not transform into the α-phase or only transforms into a small amount of the α-phase, thereby ensuring the damping performance of the titanium alloy.

[0022] In any of the above technical solutions, the high-damping, vibration-reducing superhard cutting tool is welded using vacuum diffusion welding, with a vacuum degree of 4×10⁻⁶. -3 Pa-7×10-3 Pa.

[0023] Since the tool tip and alloy layer, as well as the alloy layer and substrate layer, are connected by metal powder, vacuum diffusion welding can melt the metal powder and form a solid solution with the desired properties at the joint. This enables the assembly and bonding of high-damping, vibration-reducing superhard tools. This method requires a lower welding temperature, thus having less impact on material properties. It can be used to join materials unsuitable for fusion welding, and is simple to operate, producing welds free of various fusion welding defects. The vacuum degree of vacuum diffusion welding is 4 × 10⁻⁶. -3 Pa-7×10 -3 Pa.

[0024] In any of the above technical solutions, during the heating process of the assembly, when the temperature rises to 800°C, pressure is applied and maintained at 15MPa.

[0025] The cutting head, alloy layer and substrate layer are assembled in sequence to obtain an assembly. The assembly is then heated. When the temperature rises to 800℃, the pressure is maintained at about 15MPa. The pressurization operation is beneficial to the stability of the joint connection and has a certain effect on reducing or preventing diffusion pores.

[0026] In any of the above technical solutions, during the cooling process of the tool assembly, the pressure is gradually released when the cooling rate is 40℃ / min-60℃ / min, and when the temperature of the tool assembly drops to 600℃, the pressure drops to 0MPa.

[0027] The manufacturing process requires cooling the high-temperature tool assembly. Since pressure was applied during the initial heating phase, gradual depressurization is necessary during cooling. Depressurization can begin when the tool assembly is cooled at a rate of 40°C / min to 60°C / min, as this higher cooling rate facilitates depressurization. When the tool assembly temperature drops from 800°C to 600°C, the pressure decreases to 0 MPa.

[0028] By adopting the technical solution of the present invention, the following technical effects can be achieved:

[0029] This invention provides a high-damping, vibration-reducing superhard cutting tool. By placing an alloy layer between the tool tip and the substrate layer, the damping performance of the high-damping, vibration-reducing superhard cutting tool is improved. This not only enhances the quality of the machined surface and the efficiency of hard turning but also reduces vibrations generated during cutting. Using polycrystalline cubic boron nitride as the tool tip material ensures that the high-damping, vibration-reducing superhard cutting tool possesses high hardness, high thermal stability, good chemical stability, and good weldability, guaranteeing the overall performance of the tool. Using cemented carbide as the substrate layer material ensures that the high-damping, vibration-reducing superhard cutting tool has high hardness, toughness, and thermal conductivity. The proportions of each component in the titanium alloy ensure that the titanium alloy has good damping properties, thereby guaranteeing the vibration reduction performance of the high-damping, vibration-reducing superhard cutting tool. The combination of the tool tip, substrate layer, and alloy layer reduces chatter generated by the high-damping, vibration-reducing superhard cutting tool during cutting operations and also reduces the surface roughness of the workpiece after machining. Attached Figure Description

[0030] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0031] Figure 1 This is a schematic diagram of the structure of a high-damping, vibration-reducing superhard cutting tool provided in an embodiment of the present invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1-Cutter head; 2-Base layer; 3-Alloy layer. Detailed Implementation

[0034] To make the above-mentioned objectives, features, and advantages of the present invention more apparent and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] An embodiment of the present invention provides a high-damping, vibration-reducing superhard cutting tool, comprising: a cutting head 1, which is polycrystalline cubic boron nitride; a substrate layer 2, which is cemented carbide; and an alloy layer 3, which is a titanium alloy, disposed between the cutting head 1 and the substrate layer 2; wherein the titanium alloy comprises: titanium, 65%-75%; niobium, 12%-20%; molybdenum, 5%-7%; vanadium, 5%-15%; iron, 2.5%-5%; chromium, 4.5%-8.5%; and aluminum, 1%-2%.

[0036] like Figure 1As shown, the present invention provides a high-damping, vibration-reducing superhard cutting tool. By placing an alloy layer 3 between the tool tip 1 and the substrate layer 2, the damping performance of the high-damping, vibration-reducing superhard cutting tool is improved. This not only enhances the quality of the machined surface and the efficiency of hard turning, but also reduces the vibration generated during cutting. Using polycrystalline cubic boron nitride as the material of the tool tip 1 ensures that the high-damping, vibration-reducing superhard cutting tool has high hardness, high thermal stability, good chemical stability, and good weldability, thus guaranteeing the overall performance of the high-damping, vibration-reducing superhard cutting tool. Using cemented carbide as the material of the substrate layer 2 ensures that the high-damping, vibration-reducing superhard cutting tool has high hardness, toughness, and thermal conductivity.

[0037] The titanium alloy comprises: titanium (65%-75%), niobium (12%-20%), molybdenum (5%-7%), vanadium (5%-15%), iron (2.5%-5%), chromium (4.5%-8.5%), and aluminum (1%-2%). The titanium alloy contains a significant amount of β-stabilizing elements, such as niobium, molybdenum, vanadium, iron, and chromium. During rapid cooling after welding, these elements ensure that the β phase in the titanium alloy does not transform into the α phase, or only a small amount transforms into the α phase, thus guaranteeing the damping performance of the titanium alloy. Furthermore, aluminum serves as a strengthening element. The proportions of each component in the titanium alloy ensure its good damping performance, thereby guaranteeing the vibration reduction performance of high-damping, vibration-damping superhard cutting tools. More preferably, the titanium alloy comprises: titanium, 68%-72%; niobium, 14%-18%; molybdenum, 5.5%-6.5%; vanadium, 8%-12%; iron, 3%-4%; chromium, 5%-8%; and aluminum, 1.2%-1.8%. For example, the substrate layer 2 can be made of tungsten-cobalt cemented carbide, specifically YG8 or YG6, which possesses excellent bending, compressive, and wear resistance properties. The combination of the tool tip 1, substrate layer 2, and alloy layer 3 reduces chatter generated by high-damping, vibration-reducing superhard tools during cutting operations, and also reduces the surface roughness of the workpiece after machining.

[0038] In some embodiments of this application, the thickness of the titanium alloy accounts for 30%-40% of the thickness of the high-damping, vibration-reducing, superhard cutting tool.

[0039] By placing and connecting the titanium alloy between the cutting head 1 and the substrate layer 2, the resulting high-damping superhard cutting tool exhibits high damping performance. Excessive titanium alloy thickness compromises the overall performance of the high-damping superhard cutting tool, while insufficient thickness results in poor vibration damping. Setting the titanium alloy thickness to 30%-40% of the total thickness of the high-damping superhard cutting tool ensures both high hardness and high toughness, while also maintaining optimal high damping performance, thereby improving its vibration damping capabilities. More preferably, the titanium alloy thickness accounts for 33%-37% of the total thickness of the high-damping superhard cutting tool.

[0040] In some embodiments of this application, the surface roughness of the titanium alloy is 3μm-12μm.

[0041] The titanium alloy has a certain surface roughness, which ensures high stability of the connection between the cutting head 1 and the base layer 2 and the alloy layer 3, thereby preventing the high-damping, vibration-reducing superhard tool from splitting during cutting operations. Specifically, the surface roughness of the titanium alloy is 3μm-12μm, and more preferably, it is 5μm-10μm.

[0042] In some embodiments of this application, silver powder and copper powder are provided between the cutter head 1 and the alloy layer 3; and / or copper powder is provided between the alloy layer 3 and the substrate layer 2.

[0043] like Figure 1 As shown, by placing silver powder and copper powder between the cutting head 1 and the alloy layer 3, the cutting head 1 and the alloy layer 3 are firmly connected. During the welding process, silver, due to its low melting point, melts first. Therefore, under the same heating conditions, silver increases the diffusion efficiency of the active element titanium in the alloy layer 3 between the alloy layer 3 and the cutting head 1. The cutting head 1, being relatively stable, combines with the active element titanium in the alloy layer 3 to form a high-strength joint. By placing copper powder between the alloy layer 3 and the base layer 2, the alloy layer 3 and the base layer 2 are firmly connected. Because copper has a high melting point, and both the alloy layer 3 and the base layer 2 are alloy materials, a high-strength joint can be obtained without the titanium element in the alloy layer 3 diffusing to the base layer 2. Since the surface of the titanium alloy has a certain roughness, the metal powder easily adheres to the surface of the titanium alloy, requiring a small amount of metal powder. The combination and combined action of the titanium alloy and the metal powder can act as solder, achieving the connection between the alloy layer 3 and the cutting head 1 or the base layer 2.

[0044] In some embodiments of this application, the silver powder has a particle size of less than 200 mesh; and / or the copper powder has a particle size of less than 200 mesh.

[0045] If the particle size of the metal powder is too small, it can easily cause excessive solder extrusion and uneven weld gaps when applied to the weld, thus adversely affecting the wear and service life of the high-damping, vibration-damping, superhard cutting tools. If the particle size of the metal powder is too large, it can cause insufficient alloying between powder particles and reduced weld strength. Therefore, a particle size range of less than 200 mesh is selected for the metal powder to ensure the welding quality of the high-damping, vibration-damping, superhard cutting tools. More preferably, the particle size of the silver powder is less than 150 mesh, and the particle size of the copper powder is less than 150 mesh.

[0046] In some embodiments of this application, the mass ratio of silver powder to copper powder between the cutter head 1 and the alloy layer 3 is 1:3 to 1:2.

[0047] Silver powder and copper powder are provided between the cutter head 1 and the alloy layer 3, and the content of copper powder is controlled to be greater than that of silver powder. On the one hand, silver powder melts first due to its lower melting point, thereby improving the diffusion efficiency of the active element titanium in the alloy layer 3 between the cutter head 1 and the alloy layer 3. On the other hand, copper powder has the advantage of lower cost.

[0048] The present invention provides a method for preparing a high-damping, vibration-damping superhard cutting tool. The method is used to prepare the high-damping, vibration-damping superhard cutting tool as described above, and includes the following steps: assembling the cutting head, alloy layer, and substrate layer sequentially to obtain an assembly; heating the assembly at a rate of 8°C / min-10°C / min to 900°C-1000°C and holding it at that temperature for 30-60 minutes to obtain a cutting tool assembly; cooling the cutting tool assembly, first cooling it at a rate of 5°C / min-10°C / min to 750°C-800°C, then cooling it at a rate of 40°C / min-60°C / min to 200°C-250°C and holding it at that temperature for 30 minutes, and finally cooling it at a rate of 5°C / min-10°C / min to room temperature to obtain the high-damping, vibration-damping superhard cutting tool.

[0049] The present invention provides a method for preparing a high-damping, vibration-reducing superhard cutting tool. The tool tip, alloy layer, and substrate layer are assembled sequentially to obtain an assembly. The alloy layer is positioned in the middle layer, giving the high-damping, vibration-reducing superhard cutting tool high damping performance, thereby reducing chatter. The assembly is then heated to weld its components together. First, the temperature is increased to 900℃-1000℃ at a rate of 8℃ / min-10℃ / min and held for 30min-60min. Under these conditions, the tool tip and... The alloy layers are interconnected with each other and with the substrate layer to form a tool assembly. The high-temperature tool assembly is then cooled at a rate of low speed followed by high speed and finally low speed. Specifically, it is first cooled to 750°C-800°C at a rate of 5°C / min-10°C / min, then cooled to 200°C-250°C at a rate of 40°C / min-60°C / min, held at that temperature for 30 minutes, and finally cooled to room temperature at a rate of 5°C / min-10°C / min. This yields the high-damping, vibration-reducing superhard tool of this embodiment. More preferably, the assembly is heated at a rate of 8.5°C / min-9.5°C / min, and the tool assembly is first cooled at a rate of 6.5°C / min-8.5°C / min, then cooled at a rate of 45°C / min-55°C / min, and finally cooled to room temperature at a rate of 6.5°C / min-8.5°C / min.

[0050] It should be noted that for welding, the slower the cooling rate, the lower the residual stress. Slow cooling prevents high-damping superhard tools from developing residual stress due to rapid cooling, thus avoiding cracks or fractures and ensuring their high hardness and toughness. However, titanium alloys contain a large number of β-phase stabilizing elements. To prevent the β-phase from transforming into the α-phase, a faster cooling rate is preferable. Therefore, during the welding cooling process, when the temperature drops to 750℃-800℃, rapid cooling is necessary to ensure that the β-phase does not transform into the α-phase or only partially transforms, thereby guaranteeing the damping performance of the titanium alloy. In the staged cooling process, slow cooling aims to reduce residual stress, while rapid cooling aims to prevent phase transformation.

[0051] In some embodiments of this application, the high-damping, vibration-reducing superhard cutting tool is welded using vacuum diffusion welding, with a vacuum level of 4×10⁻⁶. -3 Pa-7×10 -3 Pa.

[0052] Since the tool tip and alloy layer, as well as the alloy layer and substrate layer, are connected by metal powder, vacuum diffusion welding can melt the metal powder and form a solid solution with the desired properties at the joint. This enables the assembly and bonding of high-damping, vibration-reducing superhard tools. This method requires a lower welding temperature, thus having less impact on material properties. It can be used to join materials unsuitable for fusion welding, and is simple to operate, producing welds free of various fusion welding defects. The vacuum degree of vacuum diffusion welding is 4 × 10⁻⁶. -3 Pa-7×10 -3 Pa, more preferably, the vacuum degree of vacuum diffusion welding is 5 × 10 Pa. -3 Pa-6×10 -3 Pa.

[0053] In some embodiments of this application, during the heating process of the assembly, when the temperature rises to 800°C, pressure is applied and maintained at 15 MPa.

[0054] The cutting head, alloy layer, and substrate layer are assembled sequentially to obtain an assembly. The assembly is then heated, and when the temperature reaches 800°C, the pressure is maintained at approximately 15 MPa. This pressurization improves the stability of the joint connection and has a certain effect on reducing or preventing diffusion porosity. It should be noted that pressurization is not limited to a temperature of 800°C; a range around 800°C and a pressure around 15 MPa can also be selected to improve the stability of the joint connection. Those skilled in the art can choose the appropriate setting based on the specific circumstances.

[0055] In some embodiments of this application, during the cooling process of the tool assembly, the pressure is gradually released when cooling at a rate of 40°C / min to 60°C / min, and when the temperature of the tool assembly drops to 600°C, the pressure drops to 0 MPa.

[0056] The manufacturing process requires cooling the high-temperature tool assembly. Since pressure was applied during the initial heating phase, gradual depressurization is necessary during cooling. Preferably, depressurization can be initiated when the tool assembly is cooled at a rate of 40°C / min to 60°C / min, as this higher cooling rate facilitates depressurization. When the temperature of the tool assembly drops from 800°C to 600°C, the pressure decreases to 0 MPa.

[0057] Example 1

[0058] An embodiment of the present invention provides a high-damping, vibration-damping, superhard cutting tool, comprising: a cutting head 1, which is polycrystalline cubic boron nitride; a substrate layer 2, which is cemented carbide; and an alloy layer 3, which is a titanium alloy, disposed between the cutting head 1 and the substrate layer 2. The titanium alloy comprises: titanium, 66%; niobium, 13.3%; molybdenum, 5.5%; vanadium, 7%; iron, 3%; chromium, 4%; and aluminum, 1.2%. The thickness of the titanium alloy accounts for 33% of the total thickness of the high-damping, vibration-damping, superhard cutting tool; the surface roughness of the titanium alloy is 5 μm. Silver powder and copper powder are disposed between the cutting head 1 and the alloy layer 3; copper powder is disposed between the alloy layer 3 and the substrate layer 2. The silver powder has a particle size of 200 mesh, and the copper powder has a particle size of 200 mesh; the mass ratio of silver powder to copper powder between the cutting head 1 and the alloy layer 3 is 1:3.

[0059] Example 2

[0060] An embodiment of the present invention provides a high-damping, vibration-damping, superhard cutting tool, comprising: a cutting head 1, which is polycrystalline cubic boron nitride; a substrate layer 2, which is cemented carbide; and an alloy layer 3, which is a titanium alloy, disposed between the cutting head 1 and the substrate layer 2. The titanium alloy comprises: titanium, 65%; niobium, 14%; molybdenum, 5%; vanadium, 7%; iron, 2.5%; chromium, 4.5%; and aluminum, 2%. The thickness of the titanium alloy accounts for 35% of the total thickness of the high-damping, vibration-damping, superhard cutting tool; the surface roughness of the titanium alloy is 7 μm. Silver powder and copper powder are disposed between the cutting head 1 and the alloy layer 3; copper powder is disposed between the alloy layer 3 and the substrate layer 2. The silver powder has a particle size of 200 mesh, and the copper powder has a particle size of 200 mesh; the mass ratio of silver powder to copper powder between the cutting head 1 and the alloy layer 3 is 1:3.

[0061] Example 3

[0062] An embodiment of the present invention provides a high-damping, vibration-damping, superhard cutting tool, comprising: a cutting head 1, which is polycrystalline cubic boron nitride; a substrate layer 2, which is cemented carbide; and an alloy layer 3, which is a titanium alloy, disposed between the cutting head 1 and the substrate layer 2. The titanium alloy comprises: titanium, 70%; niobium, 12%; molybdenum, 5.3%; vanadium, 5%; iron, 2.5%; chromium, 4%; and aluminum, 1.2%. The thickness of the titanium alloy accounts for 37% of the total thickness of the high-damping, vibration-damping, superhard cutting tool; the surface roughness of the titanium alloy is 10 μm. Silver powder and copper powder are disposed between the cutting head 1 and the alloy layer 3; copper powder is disposed between the alloy layer 3 and the substrate layer 2. The silver powder has a particle size of 150 mesh, and the copper powder has a particle size of 150 mesh; the mass ratio of silver powder to copper powder between the cutting head 1 and the alloy layer 3 is 1:2.

[0063] Example 4

[0064] An embodiment of the present invention provides a method for preparing a high-damping, vibration-damping superhard cutting tool, comprising the following steps: sequentially assembling a cutting head, an alloy layer, and a substrate layer to obtain an assembly; heating the assembly to 900°C at a rate of 8°C / min and holding it at that temperature for 30 min to obtain a cutting tool assembly; cooling the cutting tool assembly by first cooling it to 750°C at a rate of 5°C / min, then cooling it to 200°C at a rate of 40°C / min and holding it at that temperature for 30 min, and finally cooling it to room temperature at a rate of 5°C / min to obtain the high-damping, vibration-damping superhard cutting tool.

[0065] Example 5

[0066] An embodiment of the present invention provides a method for preparing a high-damping, vibration-damping superhard cutting tool, comprising the following steps: assembling a cutting head, an alloy layer, and a substrate layer sequentially to obtain an assembly; heating the assembly to 950°C at a rate of 9°C / min and holding it at that temperature for 45 min to obtain a cutting tool assembly; cooling the cutting tool assembly, first cooling it to 775°C at a rate of 7°C / min, then cooling it to 225°C at a rate of 50°C / min and holding it at that temperature for 30 min, and finally cooling it to room temperature at a rate of 7°C / min to obtain the high-damping, vibration-damping superhard cutting tool.

[0067] Example 6

[0068] An embodiment of the present invention provides a method for preparing a high-damping, vibration-damping superhard cutting tool, comprising the following steps: sequentially assembling a cutting head, an alloy layer, and a substrate layer to obtain an assembly; heating the assembly to 1000°C at a rate of 10°C / min and holding it at that temperature for 60 min to obtain a cutting tool assembly; cooling the cutting tool assembly by first cooling it to 800°C at a rate of 10°C / min, then cooling it to 250°C at a rate of 60°C / min and holding it at that temperature for 30 min, and finally cooling it to room temperature at a rate of 10°C / min to obtain the high-damping, vibration-damping superhard cutting tool.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-damping, vibration-reducing superhard cutting tool, characterized in that, include: The cutting head (1) is a polycrystalline cubic boron nitride. The substrate layer (2) is a hard alloy; Alloy layer (3), wherein the alloy layer (3) is a titanium alloy, and the alloy layer (3) is disposed between the cutting head (1) and the substrate layer (2); The titanium alloy comprises: titanium, 65%-75%; niobium, 12%-20%; molybdenum, 5%-7%; vanadium, 5%-15%; iron, 2.5%-5%; chromium, 4.5%-8.5%; and aluminum, 1%-2%. The thickness of the titanium alloy accounts for 30%-40% of the thickness of the high-damping, vibration-reducing, superhard cutting tool; The surface roughness of the titanium alloy is 3μm-12μm.

2. The high-damping, vibration-reducing superhard cutting tool according to claim 1, characterized in that, Silver powder and copper powder are provided between the cutting head (1) and the alloy layer (3); and / or copper powder is provided between the alloy layer (3) and the substrate layer (2).

3. The high-damping, vibration-reducing superhard cutting tool according to claim 2, characterized in that, The silver powder has a particle size of less than 200 mesh; and / or The copper powder has a particle size of less than 200 mesh.

4. The high-damping, vibration-reducing superhard cutting tool according to claim 2, characterized in that, The mass ratio of silver powder to copper powder between the cutting head (1) and the alloy layer (3) is 1:3-1:

2.

5. A method for preparing a high-damping, vibration-damping superhard cutting tool, the method being used to prepare a high-damping, vibration-damping superhard cutting tool as described in any one of claims 1 to 4, characterized in that, Includes the following steps: The cutting head, the alloy layer, and the substrate layer are assembled sequentially to obtain an assembly; The assembly is heated to 900℃-1000℃ at a rate of 8℃ / min-10℃ / min and held at that temperature for 30min-60min to obtain the tool assembly. The tool assembly is cooled first at a rate of 5℃ / min-10℃ / min to 750℃-800℃, then at a rate of 40℃ / min-60℃ / min to 200℃-250℃, held at that temperature for 30 min, and finally cooled to room temperature at a rate of 5℃ / min-10℃ / min to obtain the high-damping, vibration-reducing superhard tool.

6. The preparation method according to claim 5, characterized in that, The high-damping, vibration-reducing, superhard cutting tool is welded using vacuum diffusion welding with a vacuum level of 4×10⁻³ Pa to 7×10⁻³ Pa.

7. The preparation method according to claim 5, characterized in that, During the heating process of the assembly, when the temperature rises to 800°C, pressure is applied and maintained at 15 MPa.

8. The preparation method according to claim 7, characterized in that, During the cooling process of the tool assembly, the pressure is gradually released when cooling at a rate of 40℃ / min-60℃ / min. When the temperature of the tool assembly drops to 600℃, the pressure drops to 0MPa.

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