Solid sweating bionic tool, dry cutting cooling method and manufacturing process

Abstract

The present invention relates to the field of cutting tool technology, and in particular to a solid sweating bionic tool, a dry cutting cooling method and a manufacturing process. The tool body has a cutting edge area, and the tool body is a matrix phase material. A bag-shaped solid phase material is added to the matrix phase material of the cutting edge area. The melting point of the solid phase material is lower than the melting point of the matrix phase material. Part of the solid phase is exposed on the surface of the matrix phase, and part is embedded in the surface of the matrix phase. The solid phase can be heated to form an air film covering the surface of the tool. The air film can block the cutting heat from being transferred to the tool, and can form phase change heat dissipation when the air film ruptures. The present invention designs a sweating structure in the tool edge area, and uses the low-melting-point material to absorb heat through vaporization phase change to form a dynamic air film, thereby achieving precise cooling of the core cutting area, extending the tool life, and avoiding the use of cutting fluid.

Description

Technical Field

[0001] The present invention relates to the technical field of cutting tools, and in particular to a solid sweating bionic tool, a dry cutting cooling method and a manufacturing process. Background Art

[0002] During the cutting process, the tool's edge zone load-bearing environment is characterized by small area, high force and high temperature. The load gradient in the tool edge zone varies greatly. Thermal load is the primary factor that accelerates tool failure and inhibits tool speed and efficiency improvement. Therefore, the design and development of high-performance tools must focus on cooling technology to achieve efficient cooling effects, improve tool life, and at the same time reduce the pollution of traditional cutting fluids to the environment and the impact of cutting heat on machine tool errors.

[0003] Traditional cutting cooling methods typically involve pouring or spraying liquid media such as cutting oil or emulsions onto the cutting area, using these media to cool and lubricate the area. Based on the concept of "green cutting," cooling technologies such as high-speed dry cutting, cryogenic cooling, minimal lubrication, and biodegradable cutting fluids have emerged. High-speed dry cutting refers to a process that uses no or minimal cutting fluid during high-speed cutting; cryogenic cooling uses cryogenic media such as liquid nitrogen to cool the cutting area; minimal lubrication uses compressed air to atomize a very small amount of lubricant and spray it onto the cutting area; and biodegradable cutting fluids use biodegradable, environmentally friendly cutting fluids to minimize environmental impact.

[0004] The existing technology has the following technical problems:

[0005] First, when the traditional cutting cooling method sprays cutting fluid into the cutting work area, due to the existence of cutting contact pressure, the coolant mostly forms a boundary lubrication film around the tool-chip and tool-work contact areas, making it difficult to enter the core high-temperature cutting area and effectively reduce the cutting temperature. Excessive cutting fluid will cause harm to the environment and human body.

[0006] Secondly, although cooling technologies such as high-speed dry cutting, low-temperature cooling, minimal lubrication and biodegradable cutting fluids can improve tool life to a certain extent, during efficient cutting, the air turbulence generated by the high-speed rotating tool or workpiece will interfere with the flow of coolant. A large amount of coolant will disperse before reaching the cutting edge and cannot accurately reach the cutting core area, making it difficult to effectively flush and cool the tool surface, and thus cannot achieve the best cooling effect.

[0007] In addition, from the perspective of cutting fluid supply methods, the current cooling methods all supply cutting fluid from the outside of the tool-workpiece and tool-chip contact areas to the inside (even with the internal cooling method, the coolant is supplied from the near-cutting area of ​​the tool shank or insert), and the coolant cannot directly act on the core cutting heat area; from the perspective of heat absorption properties, except for the liquid nitrogen low-temperature cooling method, most of the current cooling methods use material convection heat transfer, and rarely can form an efficient heat absorption effect of medium phase change. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the present invention aims to provide a solid biomimetic cutting tool. By designing a biomimetic cutting tool with a biomimetic structure in the cutting edge, the tool utilizes the heat absorption from the vaporization phase transition of a low-melting-point material to form a dynamic air film. This allows for precise cooling of the core cutting zone, extending tool life while eliminating the need for cutting fluids. This invention significantly improves tool life and machined surface quality, reduces core cutting zone temperature, and reduces environmental pollution associated with the use of traditional emulsions and oil-based cutting fluids.

[0009] In order to achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0010] A solid sweating bionic tool, the tool body having a cutting edge area, the tool body being a matrix phase material, a bag-shaped solid-sweating phase material being added to the matrix phase material of the cutting edge area, the melting point of the solid-sweating phase material being lower than that of the matrix phase material, part of the solid-sweating phase being exposed on the surface of the matrix phase and part of the solid-sweating phase being embedded in the surface of the matrix phase; the solid-sweating phase being able to form an air film covering the tool surface when heated, the air film being able to block the cutting heat from being transferred to the tool and forming phase change heat dissipation when the air film is ruptured.

[0011] Optionally, the melting point of the solid phase is lower than the temperature of the core region during cutting by the tool.

[0012] Optionally, the solid phase is distributed in at least one area of ​​the rake face, flank face, chip breaker groove and table surface of the cutting edge area.

[0013] Optionally, the area of ​​the hair-solidifying phase exposed on the surface of the matrix phase is smaller than the area of ​​the portion embedded in the surface.

[0014] Optionally, the diameter of the exposed portion of the hair-fixing phase ranges from 0.1 to 1.0 mm, the maximum diameter of the pouch ranges from 2.0 to 3.0 mm, and the depth of the pouch ranges from 0.5 to 1.0 mm.

[0015] Optionally, the volume of the solid phase accounts for 5%-15% of the total volume of the tool material.

[0016] Optionally, the matrix phase is cemented carbide or ceramic, and the solid phase is lead, zinc or copper.

[0017] Optionally, the shape of the tool is circular, triangular, square, diamond or irregular.

[0018] An embodiment of the present invention also provides a dry cutting cooling method using the solid sweating bionic tool as described above. During the cutting process, the solid phase in the cutting edge area of ​​the tool is vaporized by the cutting heat to form an air film covering the surface of the tool; the air film is tightly attached to the tool surface through intermolecular forces, blocking the cutting heat from being transferred to the tool; when the air film ruptures, a phase change heat dissipation method is formed in which the solid turns into gas, and the solid phase in the sub-surface layer continues to vaporize to replenish the air film, forming a cyclic cooling process.

[0019] An embodiment of the present invention also provides a manufacturing process for a solid sweating bionic tool as described above: the tool is made by additive manufacturing; during the additive manufacturing process, the interface between the matrix phase and the solid phase is regulated by adjusting the laser power, scanning path, scanning rate and powder supply of the matrix phase and the solid phase deposition, while ensuring the area of ​​the solid phase exposed on the outer surface and the capacity of the solid phase embedded in the sub-surface; the formed tool is sintered and densified to finally obtain a solid sweating bionic tool with a composite structure.

[0020] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

[0021] 1. The solid sweating bionic tool of the present invention comprises a matrix phase and a solid phase, wherein the matrix phase is the main material of the tool and the solid phase is a low melting point alloy. The solid phase is distributed in the surface and sub-surface of the cutting edge area in a sac-like structure. The sac-like structure allows the solid phase to have a larger area in the sub-surface, ensuring sufficient sweating. The small area of ​​the exposed part can reduce the impact on the overall mechanical properties of the tool. The two work together to achieve efficient cooling while maintaining the hardness and strength of the tool as much as possible. When the cutting heat is conducted to the solid phase, it vaporizes to form an air film, covering the surface of the tool to block heat transfer; after the air film ruptures, phase change heat dissipation is formed, and the solid phase in the sub-surface continues to vaporize and replenish, forming dynamic cycle cooling. By designing a sweating bionic structure at the tool end, efficient heat insulation and heat dissipation effects are achieved, thereby achieving the cooling purpose in dry cutting. In addition, the toughness of the solid phase can be used to improve the ability of the tool matrix phase to resist fracture.

[0022] 2. After adopting the solid sweating bionic tool of the present invention, there is no need to use traditional oily cutting fluid or emulsified cutting fluid, and efficient cooling of dry cutting is achieved. The cooling effect is improved by 3 to 4 times, achieving the effect of traditional water cooling and oil cooling, and greatly realizing environmentally friendly processing.

[0023] 3. Because the low-melting-point phase in solid-sweating bionic cutting tools is distributed in the surface and subsurface layers of a small area of ​​the tool's cutting edge, its volume content is small compared to the overall blade (sweating does not require a large amount of sweat to achieve a cooling effect). Therefore, it does not significantly affect the mechanical properties of the surface layer of the matrix phase. This is significantly different from the use of sweating materials in aerospace (the sweating structure of cutting tools must achieve efficient local cooling in a very small area while avoiding negative impacts on the overall mechanical properties of the tool, while aerospace sweating materials focus more on long-term stability in large-scale high-temperature environments). At the same time, compared to the brittleness of traditional ceramic tools, the low-melting-point phase in solid-sweating tools has better toughness, which can improve the tool's cutting edge area's ability to resist crack growth.

[0024] 4. The solid sweating phase of the solid sweating bionic tool is embedded in the surface and sub-surface of the tool (the depth exceeds the crater wear depth of traditional tools), thus providing a stable phase change source for the formation and gasification of the air film, ensuring that the tool still has a cooling effect after the edge area is worn.

[0025] 5. The cooling medium is directly sent into the core heating area of ​​the cutting. By using a small amount of cooling medium, an efficient cooling effect is achieved, the heating of high-end equipment is reduced, the impact of cutting heat on thermal machine tool errors is reduced, and the manufacturing efficiency and manufacturing accuracy of high-end equipment are improved.

[0026] 6. Solid-state sweating: After the low-melting-point solid phase in a bionic tool sweats, a gas film first forms on the tool face. This film possesses a certain rigidity (after the low-melting-point material vaporizes, the gas molecules form a dense layer on the tool surface. Due to intermolecular forces and dynamic airflow pressure, the film exhibits solid-like properties and is not easily dispersed by cutting forces. This film, in turn, resists external pressures such as chip impact and cutting forces during the cutting process). It is also relatively thin. Due to its short contact distance with the tool face, the molecular van der Waals forces keep it tightly attached to the cutting edge, isolating the workpiece from the cutting zone and protecting the tool from high temperatures. When the film reaches a certain thickness, it ruptures and vaporizes, forming a solid-to-gas phase transition. This phase transition absorbs significant cutting heat, reducing the temperature in the cutting zone. This cooling method can increase the tool's cutting life by 1.5-2 times, improve surface quality by 1 / 3-1 / 2 times, and maintain a stable temperature of 400-500°C in the cutting core.

[0027] 7. The formation of complex-shaped structures is achieved through additive manufacturing technology, which provides a preparation method for the creation of a pore skeleton structure of a high-melting-point matrix in the sweating material and the incorporation of a low-melting-point solid phase; through additive manufacturing technology, a new type of solid sweating bionic tool is developed to achieve efficient cutting cooling, effectively solving the problem of large cutting heat control caused by the increase in cutting speed.

[0028] Additional advantages of the present invention will be given in the description which follows, and in part will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] To more clearly illustrate the embodiments of this application or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are only some of the embodiments described in this application. For those skilled in the art, other drawings can be derived from these drawings without inventive effort. In addition, the spacing or size between components is exaggerated to show the position of each component, and the schematic diagrams are for illustrative purposes only.

[0030] Figure 1 Schematic diagram of the tool structure and the solid phase layout provided by an embodiment of the present invention, wherein the right side is a cross-sectional view at position AA in the left side diagram;

[0031] Figure 2 Schematic diagram of the distribution of the hair-solidifying phase in the matrix phase provided by an embodiment of the present invention;

[0032] Figure 3 is a schematic diagram of the shape of a tool provided by an embodiment of the present invention, wherein Figure 3 (a) is a circular tool, Figure 3 (b) is a triangular tool, Figure 3 (c) is a square tool, Figure 3 (d) is a diamond-shaped tool;

[0033] Figure 4 Schematic diagram of a tool sweating cooling method provided by an embodiment of the present invention;

[0034] Figure 5 Schematic diagram of a tool additive manufacturing method provided by an embodiment of the present invention; DETAILED DESCRIPTION

[0035] It should be noted that the following detailed description is illustrative and is intended to further illustrate the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0036] Explanation of terms:

[0037] Sweating cooling: It is proposed based on the principle that the body controls its body temperature by evaporating sweat. In engineering, by designing and manufacturing a sweating structure, the material can reduce its surface temperature by "sweating" in a high-temperature environment, thereby achieving the purpose of cooling. Among them, the sweating material is usually made of a porous matrix made of a high-melting-point metal, and then a low-melting-point metal is infiltrated into the porous matrix. Under high temperature, the low-melting-point metal evaporates and absorbs heat to cool the surface of the material. The application of this technology requires external conditions that can "sweate", that is, first, there must be a high external temperature condition to promote the vaporization of the low-melting-point body, second, there must be technology that can achieve the mutual doping of the high-melting-point matrix and the low-melting-point component, and third, the material itself has certain mechanical properties before and after "sweating", and the mechanical properties cannot be excessively reduced due to the "sweating" structure.

[0038] Example 1

[0039] like Figure 1 As shown, this embodiment proposes a solid sweating bionic tool, thereby achieving the following effects: (1) a sweating bionic structure is designed at the tool end, and the structure is realized by additive manufacturing. The area of ​​the structure should be small to avoid affecting the overall mechanical properties of the tool; (2) the solid low-melting-point material in the micro-region of the tool cutting edge is vaporized by the cutting heat and becomes an air film attached to the tool surface, forming a high-efficiency heat insulation and thermal insulation effect; (3) no cutting fluid is used in the cutting process, cooling is achieved in dry cutting, and low-carbon green manufacturing is achieved.

[0040] like Figure 1 、 Figure 2 As shown, the solid sweating bionic tool includes a matrix phase and a solid phase (solid sweating phase), the melting point of the solid phase is lower than the melting point of the matrix phase; the solid phase is a sac-like structure, and the solid phase is distributed in the cutting edge area of ​​the tool, the cutting edge area has a surface layer and a sub-surface layer, part of the solid phase is exposed in the surface layer, and part is embedded in the sub-surface layer; the solid phase is heated to form an air film covering the surface of the tool, the air film blocks the cutting heat from being transferred to the tool, and when the air film ruptures, phase change heat dissipation is formed.

[0041] The main function of the solid phase is to vaporize under the action of cutting heat to form an insulating gas film on the blade surface, thereby protecting the tool edge area through evaporation and insulation. In addition, the toughness of the solid phase can be used to improve the ability of the tool matrix phase to resist fracture.

[0042] By distributing the solid phase over the cutting edge, cooling is directed to the core heat-generating area, achieving efficient cooling and extending tool life. This eliminates the need for traditional cutting fluids and reduces environmental pollution. Furthermore, the sac-like structure allows the solid phase to occupy a larger subsurface area, ensuring sufficient heat release. The reduced exposed area minimizes the impact on the tool's overall mechanical properties. These two factors work synergistically to achieve efficient cooling while maintaining the tool's hardness and strength.

[0043] The melting point of the solid phase is lower than the temperature of the tool's core during cutting. Specifically, it is below 500°C. This temperature range matches the core temperature of common metal cutting (400-500°C). During the cutting process, the temperature of the tool's cutting edge typically rises. Setting the melting point of the solid phase below 500°C ensures that the solid phase melts promptly under the influence of cutting heat and forms an air film, thereby achieving effective cooling.

[0044] The solid phase is distributed in at least one area of ​​the rake face, flank face, chip breaker groove and table surface of the cutting edge area. During the cutting process, the rake face mainly bears the cutting force and cutting heat, the flank face generates frictional heat in contact with the workpiece, and the chip breaker groove and table surface play the role of chip breaking and supporting during the cutting process. Distributing the solid phase in these key areas can more effectively utilize the cooling function of the solid phase, cool the heat sources in different parts of the cutting process, and improve the cooling effect of the entire cutting area. For example, when the solid phase on the rake face is heated to form an air film, it can reduce the impact of the cutting force on the tool and lower the cutting temperature; the air film formed by the solid phase on the flank face can reduce the frictional heat transfer with the workpiece. Compared with traditional cooling methods, this targeted distribution method can more accurately solve the problem of heat generation in the cutting process, and avoid introducing low-melting-point materials in non-critical areas to affect the tool strength, thereby improving the cooling efficiency and service life of the tool.

[0045] The area of ​​the solid hair phase exposed to the surface of the matrix phase is smaller than the area of ​​the embedded sub-surface portion. Such a design helps to reduce the impact of the solid hair phase on the mechanical properties of the matrix phase surface while ensuring sufficient sweating. Because if the exposed area is too large, the solid hair phase will wear out or fall off prematurely during the cutting process, affecting the service life and cooling effect of the tool; while the embedded sub-surface portion has a larger area, it can store more solid hair phase materials, ensuring a continuous supply of substances required for the air film for a longer period of time. The setting of this area relationship is adapted to the force and heat distribution of the tool during the cutting process, so that the cooling function of the solid hair phase can be fully utilized while ensuring the structural strength of the tool. For example, during the cutting process, the surface of the matrix phase is mainly subjected to the cutting force and cutting heat, while the sub-surface is relatively less stressed. Therefore, distributing more solid hair phase in the sub-surface can achieve efficient cooling without affecting the surface performance of the matrix phase.

[0046] The exposed portion of the hair-fixing phase has a diameter range of 0.1-1.0 mm, a maximum diameter range of the sac bag of 2.0-3.0 mm, and a depth not exceeding 5-10 times the wear depth of the tool crater (≤2.0 mm). Preferably, the sac bag has a depth range of 0.5-1.0 mm.

[0047] The smaller diameter of the exposed portion facilitates the formation of a uniform and stable gas film on the surface of the matrix phase, while also reducing direct loss of the solid phase during cutting. The maximum diameter and depth of the sac ensure sufficient storage space for the solid phase in the subsurface layer, allowing for timely replenishment of vaporized material in the event of a rupture in the gas film, maintaining its continuity and stability. This reduces stress concentration while avoiding cooling interruptions caused by insufficient sweating. For tools of varying sizes, skilled artisans can adjust the exposed portion diameter and sac size to suit varying cutting conditions.

[0048] The volume of the solid phase accounts for 5%-15% of the total volume of the tool material. This volume ratio is set to ensure sufficient cooling effect while avoiding excessive solid phase affecting the overall performance of the tool. If the volume of the solid phase is too small, it cannot provide enough vaporized material to form an effective air film, resulting in poor cooling effect; while too large a volume may reduce the hardness and strength of the tool, affecting the cutting performance of the tool. By precisely controlling the volume ratio of the solid phase, a balance can be achieved between the cooling effect and the tool performance. In actual applications, according to factors such as the purpose of the tool, cutting parameters and materials, a suitable solid phase volume ratio can be selected to meet different cutting requirements.

[0049] The matrix phase is a cemented carbide (such as tungsten carbide) or a ceramic (such as aluminum oxide or silicon nitride). Cemented carbide and ceramics are common cutting tool materials with high hardness and good wear resistance, making them suitable for various cutting processes. The solid phase is made of metals with low melting points, such as lead, zinc, and copper, which melt quickly under the influence of cutting heat and form an air film. This material combination is selected based on the material properties and the actual requirements of the cutting process. The cemented carbide or ceramic matrix phase provides the basic cutting performance of the tool, while the solid phase provides cooling during the cutting process.

[0050] like Figure 3 As shown, the tool shape can be circular, triangular, square, diamond or irregular, and different tool shapes are suitable for different cutting processing requirements. By designing tools of different shapes, the scope of application of the present invention can be broadened, enabling it to play a role in cooling and improving tool life in various cutting processes.

[0051] Although sweating technology has applications in other fields, sweating cooling has not been used in cutting processing for a long time because it cannot meet the dual requirements of "high-precision sweating structure" and "stable mechanical properties" in the tool edge area. Specifically: ① Structural complexity: The sweating function requires the design of complex pores or pocket structures (such as micron-level pores) in the tool edge area. Traditional manufacturing methods (such as casting and machining) are difficult to accurately control the porous or composite structure of the surface / subsurface of the matrix phase. ② Conflict of mechanical properties: The tool needs to have both high hardness and toughness. If low-melting-point materials (such as copper and zinc) are added to the blade area through traditional processes, it is easy to cause interface cracks due to material incompatibility, thereby reducing the strength of the tool. ③ Process limitations: Traditional sintering or coating technologies cannot achieve gradient composites of low-melting-point materials and high-melting-point matrices (such as ceramics and cemented carbides).

[0052] Example 2

[0053] This embodiment provides a dry cutting cooling method using the solid sweating bionic tool described in Example 1:

[0054] The present invention makes full use of the basic principle of heat absorption when solid evaporates and turns into gas, and forms a circulating cooling method of air film insulation and phase change heat dissipation in the cutting core area. Figure 4 As shown in the figure, during the cutting process, the solid phase in the cutting edge area of ​​the tool vaporizes due to the cutting heat, forming a gas film covering the tool surface. The gas film adheres to the tool surface through intermolecular forces, effectively blocking the transfer of heat generated by cutting friction and chip deformation to the tool. If the gas film ruptures, a phase change heat dissipation process occurs, where the solid turns to gas. At this time, the solid phase in the subsurface layer continues to vaporize to replenish the gas film, thus forming a cyclic cooling process. This cooling method solves the problem of effective cooling in traditional dry cutting, achieving efficient tool cooling without cutting fluid.

[0055] Compared to traditional cooling methods, this method eliminates the need for external coolant. Instead, it leverages the heat absorption principle of the solid phase during vaporization to create a cooling effect directly within the core cutting area, improving cooling efficiency. Furthermore, the formation and rupture of the air film continuously removes cutting heat, ensuring a stable tool temperature during cutting, extending tool life, and improving machining quality and efficiency.

[0056] Example 3

[0057] This embodiment proposes a manufacturing process of the solid sweating bionic cutting tool as described in Example 1:

[0058] The tools are made by additive manufacturing, e.g. Figure 5As shown, a combined process of photolithography and spray deposition (SLA+MJ) is used for ceramic substrates, while a directed energy deposition (DED) process is used for cemented carbide substrates. During the additive manufacturing process, by adjusting parameters such as the laser power, scanning path, scanning rate, and powder feed rate for both the matrix and solid phase deposition, the interface between the matrix and solid phases can be precisely controlled, while ensuring the surface area of ​​the solid phase exposed and the volume of the solid phase embedded in the subsurface. The formed tool is then sintered and densified, ultimately resulting in a composite solid biomimetic tool structure.

[0059] This manufacturing process overcomes the difficulty of precisely controlling the distribution and structure of the solid phase in traditional manufacturing methods, making it possible to realize complex solid biomimetic cutting tools. For example, the combined process of photocuring and spray deposition can precisely shape the fine structure of ceramic-based cutting tools, while the directed energy deposition process is suitable for the manufacture of carbide-based cutting tools. By adjusting the manufacturing process parameters, the distribution of the solid phase and its integration with the matrix phase can be optimized, improving the overall performance of the tool. Sintering densification further increases the tool's density and strength, ensuring its reliability and durability during the cutting process.

[0060] Specifically:

[0061] Option 1: Use DED laser directed energy deposition of tungsten carbide (WC) as the matrix skeleton. When the material is stacked on the surface and sub-surface of the tool body, low-melting-point copper or zinc is selectively deposited as the solid phase according to the designed sweating structure. Adjust the process parameters such as laser power, scanning path, scanning rate and powder supply of the matrix WC and sweating copper or zinc phase deposition to regulate the interface between the matrix phase and the solid phase, while ensuring the area of ​​the solid phase exposed on the outer surface and the capacity of the solid phase buried in the sub-surface.

[0062] Option 2: Use the SLA process in the composite process of photocuring and spray deposition (SLA+MJ) to add the (Al2O3 or Si3N4) matrix skeleton. When the material is stacked on the surface and sub-surface of the ceramic tool body, use the MJ process to select additive copper or zinc as the solid phase according to the designed sweating structure. Then try to use low-temperature co-firing technologies such as microwave sintering, plasma sintering, and ultrasonic vibration sintering to sinter the additively formed ceramic tool into a dense tool body. Adjust the composite process parameters such as laser power, scanning path and scanning rate, and feeding rate of the matrix skeleton ceramic and sweating copper or zinc phase deposition to regulate the interface between the matrix phase and the solid phase.

[0063] To clarify the technical solution provided by this invention, we will use a ceramic-based solid self-sweating cutting tool as an example to illustrate the invention. The present invention has achieved the following: 1) completing the structural design of the solid self-sweating cutting tool; 2) designing an additive manufacturing process for the tool structure, producing a solid self-sweating cutting tool; and 3) conducting cutting experiments, achieving the desired cutting results.

[0064] (1) Structural design:

[0065] ①First, the Thirdwave simulation software was used to calculate the heat generation in the cutting zone of ceramic tools with different geometric parameters, and the cutting heat was obtained as the boundary condition for subsequent simulation calculations. The geometric parameters were set as follows: rake angle of -20~20°, back angle of 2~10°, main deflection angle of 0~90°, negative deflection angle of 0~70°, cutting edge inclination angle of -20~20°, cutting edge blunt radius of 0.1~1.0mm, tool tip radius of 0.1~1.0mm, and chip breaker (straight and circular types, etc.); the cutting parameters were set as follows: cutting speed of 100~500m / min, feed rate of 0.1~0.5mm / r, and cutting depth of 0.1~3.0mm.

[0066] ②The cutting heat distribution obtained by Thirdwave simulation calculation is input into COMSOL phase change simulation software as the boundary condition, and the amount of sweating required to stably control the cutting temperature in the cutting deformation zone below 400-500°C and the thickness of the air film required to form this sweating are calculated. Based on this, the content of solid sweating agent required to be added to the hair fixing tool is calculated according to the thermodynamic equation.

[0067] ③ Based on the cutting temperature distribution calculated by Thirdwave simulation, focus on the heated area of ​​the tool where the cutting temperature exceeds 500°C. This area will be used as the area for the solid sweating agent to be incorporated.

[0068] ④ Based on the calculation results of steps ② and ③, draw a three-dimensional diagram of the solid sweating bionic tool in three-dimensional modeling software such as AutoCAD, UG and Solidwork. The solid phase is mainly distributed around the cutting edge area of ​​the tool (including the front cutting edge, the back cutting edge, the chip breaker groove / table), and there is no solid phase distribution in the area outside the cutting edge area of ​​the tool. The solid phase content is controlled at 5~15vol% (the volume of the solid phase accounts for 5%-15% of the total volume of the tool material). Figure 1 As shown. The solid phase penetrates deep into the blade matrix phase, and its state is a capsule-like structure (such as Figure 2 As shown in the figure, the exposed part of the blade is small (the diameter of the exposed part ranges from 0.1 to 1.0 mm), while the subsurface embedded part is large (the maximum diameter of the pocket ranges from 2.0 to 3.0 mm), and the pocket depth ranges from 0.5 to 1.0 mm, so as to provide sufficient vaporized material to form an air film on the blade during sweating in the solid hair phase.

[0069] ⑤ Properties of the solid phase and matrix phase: The solid phase is a low-melting-point material, meaning it melts at the cutting temperature (melting point below 500°C), such as alloys like lead, zinc, or copper. The matrix phase is a ceramic such as alumina or silicon nitride. The primary function of the solid phase is to vaporize under the influence of cutting heat, forming an insulating film on the tool face. This evaporation and insulation protect the tool edge. The toughness of the solid phase also enhances the fracture resistance of the tool matrix phase. The solid phase is primarily distributed in the surface and subsurface regions of the cutting edge, with a depth no greater than five times the wear depth of the tool's crater (≤1.0mm). The subsurface solid phase should have a cavity capacity to maintain sufficient perspiration during perspiration. The overall solid phase content should be limited to maintain the ability to control cutting temperature without significantly affecting tool hardness.

[0070] The tool structure designed according to the above process is as follows Figure 5 As shown, the tool shapes include round, triangular, square, diamond and irregular shapes. The size of the round tool is Φ12.5*2.5mm, the size of the diamond blade is 12*12*6mm, and the size of the square blade is 11*11*2.0mm. The tool can have a chip breaker groove or not, and the solid phase is distributed on the front and back face of the tool cutting edge area.

[0071] (2) Theoretical analysis:

[0072] Based on the above technical principles and parameters, a theoretical model of air film thickness, perspiration-inducing agent content, and cutting parameters was established. The target air film thickness was set to δ , the following conditions need to be considered:

[0073] ① Air film insulation conditions:

[0074] The air film needs to block the heat flux density transmitted to the tool q ,satisfy:

[0075] ;

[0076] in: h c : Film convection heat transfer coefficient (W / m 2 ∙K), k g : Gas thermal conductivity (W / m∙K), T cut : cutting zone temperature, T tool : Tool temperature, ∆ T : Temperature difference.

[0077] ②Requirement for vaporization volume of diaphoretic agent:

[0078] The volume of gas required to form a gas film of thickness δ Vg :

[0079] ;

[0080] in, A is the area of ​​high temperature zone of tool (m 2 ), and cutting depth a p and the main deflection angle κ r Related, A ∝ a p ∙l c ( lc : cutting edge contact length).

[0081] ③Consumption of diaphoretic agent:

[0082] The diaphoretic agent is completely vaporized from the solid state (melting point < 500℃), and its volume Vs satisfy:

[0083] ;

[0084] in, ρ s , ρ g :Solid / gas density of diaphoretic agent (kg / m 3 ), V g : Gas volume required for air film.

[0085] ④Constraints of sweating agent content and tool structure:

[0086] Effective sweat volume V s Provided by the total volume of diaphoretic agent in the tool:

[0087] ;

[0088] in, α : Volume fraction of diaphoretic agent, V active : Effective volume of the bag in the high temperature area.

[0089] ;

[0090] in, n is the number of bags in the high temperature zone and the area A Proportional, d max is the maximum diameter of the sac, h is the depth of the sac.

[0091] Therefore, the expression of the air film thickness is:

[0092] ;

[0093] in, k struct : Pocket distribution density coefficient, which is determined by the number of pockets per unit area in the high-temperature zone, C: Cutting geometry correction coefficient, which is positively correlated with the main deflection angle.

[0094] (3) Manufacturing process:

[0095] ① First, use 3D software such as UG and Solidwork to model the hair straightening tool. The shape and structure of the tool are as follows: Figure 5 As shown, save it as an STL format model and import the STL format file into the slicing software CeraMulti Slicer.

[0096] ② The model was sliced ​​using the CeraMulti Slicer software, and the entire tool model was divided into three parts for cutting: the upper, middle, and lower parts. The upper part includes the cutting edge area of ​​the blade, contains the tool matrix phase and the solid sweat phase, and has a thickness of 1 / 5 of the overall thickness of the blade, ranging from 0.5 to 1.0 mm; the middle part contains only the tool matrix phase and does not contain the solid sweat phase, and has a thickness of 3 / 5 of the overall thickness of the blade, ranging from 2.0 to 4.0 mm; the lower part has the same blade shape, structure, and material properties as the upper part, and has a thickness of 1 / 5 of the overall thickness of the blade, ranging from 0.5 to 1.0 mm. The upper and lower regions are sliced ​​at high density, with a single-layer thickness of 0.02-0.04 mm and a total of 100-200 slices to ensure the printing accuracy of the blade shape and structure as well as the precise filling of the solid phase; the middle region is sliced ​​at low density, with a single-layer thickness of 0.05-0.1 mm and a total of 50-100 slices to ensure the printing accuracy of the blade shape and structure as well as the precise filling of the solid phase;

[0097] ③ Import the sliced ​​tool model into the multi-material CeraMulti 3D Printer and set the printing parameters: laser power of 50-150 mW, laser scanning rate of 4.0 m / s, and laser scanning spacing of 100 μm. The coating speed of the matrix ceramic paste was 1-4 mm / s, and the filling speed of the solid evaporation incorporation phase was 20-30 mm / s.

[0098] ④Start printing, printing in three parts:

[0099] 1) The lower part prints:

[0100] Feeding the material from the feed platform: Select the base phase and inject it into the feed trough, then use the feed pusher to push it upward and extrude it. Scraper spreading: The scraper evenly spreads the base phase extruded from the feed platform onto the build platform, while scraping the excess ceramic phase into the recovery bin. Laser curing: Activate the laser system and solidify the base phase area according to the print path. Nozzle slotting and spraying: Move the nozzle module above the base phase, activate the air nozzle first and then the spray nozzle. In the preset solid phase filling area, the air nozzle is responsible for slotting, while the spray nozzle supplies the solid phase material. After the solid phase spraying is completed, the laser system is activated again to solidify the solid phase according to the preset path, thus completing the printing process of one layer. After each layer is solidified, the build platform lowers by one layer thickness, and the above steps are repeated until the next layer is printed.

[0101] 2) Middle part printing (no need to fill the solid phase, only print the matrix phase):

[0102] Feeding the material from the feed platform: Select the base phase and inject it into the feed trough. The feed pusher pushes the base phase upward and out of the material. Scraper spreading: The scraper evenly spreads the base phase extruded from the feed platform onto the build platform, while scraping the excess ceramic phase into the recovery bin. Laser curing: The laser system activates and cures the base phase area along the print path. After each layer is cured, the build platform descends by one layer, and the above steps are repeated.

[0103] 3) Upper part printing: Same as upper part printing.

[0104] ⑤ After removing the printing tool, clean the surrounding uncured paste with alcohol;

[0105] ⑥ Place the cleaned multiple tool blanks into a ceramic sintering box, fill them with high-temperature resistant sealing refractory clay, place them in a high-temperature sintering furnace and sinter them at a rate of 0.5℃ / min to 1450~1650℃, then keep them warm for 120 minutes to make the samples gradually dense, and finally cool them to room temperature at a rate of 1℃ / min. The samples are sintered to complete the final solid self-sweating tool.

[0106] Although the above describes the specific embodiments of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A solid bionic sweating tool, wherein the tool body has a cutting edge area, characterized in that: The tool body is made of a matrix phase material, and a bag-shaped solid phase material is added to the matrix phase material in the cutting edge area. The melting point of the solid phase material is lower than that of the matrix phase material. Part of the solid phase is exposed on the surface of the matrix phase, and part of it is embedded in the surface of the matrix phase. The solid phase can be heated to form an air film covering the surface of the tool, and the air film can block the cutting heat from being transferred to the tool, and can form a phase change to dissipate heat when the air film ruptures; The melting point of the solid phase is lower than the temperature of the core area during cutting by the tool; The solid phase is distributed in at least one area of ​​the rake face, flank face, chip breaker groove and table surface of the cutting edge area; The area of ​​the solid phase exposed on the surface of the matrix phase is smaller than the area of ​​the portion embedded in the surface; The exposed portion of the hair-fixing phase has a diameter ranging from 0.1 to 1.0 mm, the maximum diameter of the pouch ranges from 2.0 to 3.0 mm, and the depth of the pouch ranges from 0.5 to 1.0 mm.

2. The solid sweating bionic tool according to claim 1, characterized in that: The volume of the solid phase accounts for 5%-15% of the total volume of the tool material.

3. The solid sweating bionic tool according to claim 1, characterized in that: The matrix phase is hard alloy or ceramic, and the solid phase is lead, zinc or copper.

4. The solid bionic sweating tool according to claim 1, characterized in that: The shape of the tool is circular, triangular, square, diamond or irregular.

5. A dry cutting cooling method using the solid sweating bionic tool according to any one of claims 1 to 4, characterized in that: During the cutting process, the solid phase in the cutting edge area of ​​the tool is vaporized by the cutting heat, forming an air film covering the surface of the tool; the air film adheres to the tool surface through intermolecular forces, blocking the transfer of cutting heat to the tool; when the air film ruptures, a phase change heat dissipation method of solid to gas is formed, and the solid phase in the sub-surface layer continues to vaporize to replenish the air film, forming a cyclic cooling process.

6. A process for manufacturing a solid bionic sweating tool according to any one of claims 1 to 4, characterized in that: The tool is manufactured by additive manufacturing. During the additive manufacturing process, the interface between the matrix phase and the solid phase is regulated by adjusting the laser power, scanning path, scanning rate and powder supply for deposition of the matrix phase and the solid phase, while ensuring the area of ​​the solid phase exposed on the external surface and the volume of the solid phase embedded in the subsurface. The formed tool is subjected to sintering densification treatment to finally obtain a solid sweating bionic tool with a composite structure.

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