Method for preparing multi-layer micro-texture cutter based on micron-sized laser powder bed melting and cutter

Abstract

The invention provides a method for preparing a multi-layer micro-texture tool based on micron-sized laser powder bed melting and the tool, and relates to the field of cutting tool manufacturing, and the method comprises the steps that a three-dimensional model of a multi-layer micro-texture is established, a trapezoid is translated at certain intervals in the direction of the short edge of the trapezoid, and a single-layer micro-texture is obtained; stacking two adjacent layers of single-layer microtextures according to an angle difference gamma to obtain a multi-layer microtexture; the upper surface of the printing substrate is provided with a pit with the same size as the cutter base body; under the argon protection environment, the mu-LPBF is used for preparing a tool base body, and the mu-LPBF is used for preparing a multi-layer microstructure on the front tool face of the obtained tool base body; and the obtained cutter with the multi-layer microtexture is subjected to heat treatment. According to the multi-layer microtexture, the service life of the microtexture cutter is prolonged, after the surface of the first layer is abraded, the internal microtexture is exposed, the antifriction function continues to be kept, and therefore the service life of the cutter is prolonged, and the microtexture cutter is suitable for cutting machining of materials difficult to machine such as titanium alloy and high-strength steel.

Description

Technical Field

[0001] This invention relates to the field of cutting tool manufacturing technology, specifically to a method and tool for preparing multi-layer microtextured tools based on micron-level laser powder bed melting. Background Technology

[0002] In aerospace, automotive, and mold manufacturing industries, machining technology is widely used for processing various materials. Traditional cutting tools mainly rely on material system optimization and tool shape optimization to improve performance. While this can reduce cutting forces, improve surface finish, and increase tool wear resistance, it still faces challenges such as rapid tool wear, high friction coefficients, and severe heat generation when machining difficult-to-machine materials like titanium alloys and high-strength steels. Dry metal cutting, as a green manufacturing process, leads to accelerated tool wear in the absence of cutting fluid. Therefore, microtexturing technology has become crucial for reducing friction and wear; a well-designed surface texture can significantly improve tool performance and lifespan.

[0003] For example, in invention application number CN202410097199.8, a microtextured tool based on laser microcladding in situ forming and its preparation method and application were proposed. The microtexture shape processed in situ by laser microcladding is a single layer. However, due to the large spot size and nozzle powder feeding characteristics, this method is not conducive to printing unsupported suspended structures in multi-layer microtextures. In invention application number CN202410048167.9, a biomimetic circular scale structure microtextured tool and processing method were proposed. Femtosecond laser is used to process circular scale structure microtextures, texture channels, hydrophobic grooves and straight grooves, which can suppress derivative cutting of difficult-to-machine materials. However, the single-layer microtexture produced by this method has the disadvantages of being easily damaged and blocked.

[0004] The aforementioned technologies often suffer from drawbacks such as rapid wear and short lifespan of the microtexture, resulting in significant shortcomings in tool wear resistance and friction reduction performance, failing to effectively address tool performance issues under high-load cutting conditions. These deficiencies limit the application of tools in high-performance machining, necessitating the development of novel tools to improve their cutting performance and service life. This invention proposes a multi-layer friction-reducing microtextured tool based on additive manufacturing, achieved by fabricating a multi-layer microtextured structure on the tool surface. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention aims to provide a method and tool for fabricating multi-layered microtextured cutting tools based on micron-level laser bed fusion. The method involves establishing a single-layer microtexture composed of trapezoidal V-grooves with an included angle θ, and stacking adjacent single-layer microtextures with an angle difference γ to obtain a multi-layered microtexture with reliable stability. μ-LPBF is used to achieve unsupported, suspended printing of the V-grooves, improving the shape and dimensional accuracy of the printed multi-layered microtexture. A cutting tool with this multi-layered microtexture is obtained using micron-level laser bed fusion technology. After the first layer of the multi-layered microtexture on the tool wears down, the internal microtextures are exposed and continue to reduce friction on the machining surface, thereby improving tool life. This method is suitable for machining difficult-to-machine materials such as titanium alloys and high-strength steel.

[0006] Specifically, on the one hand, this invention provides a method for preparing multilayer microtextured tools based on micron-level laser powder bed melting, the specific implementation steps of which are as follows: The method for preparing multilayer microtextured cutting tools based on micron-level laser powder bed melting is implemented as follows: S1. Establish a three-dimensional model of the multi-layered microtexture, specifically including: Set up a trapezoid with width D, height H and two waist angles α, and the lower surface of the trapezoid has a V-groove with an included angle θ1; according to the material of the tool and the cutting environment and cutting conditions, translate the trapezoid along the direction of the short side of the trapezoid at intervals of 10~40μm to obtain a single-layer microtexture; By stacking two adjacent single-layer microtextures with an angle difference γ, multiple layers of microtexture are obtained. Based on the overhang length P and the trapezoidal spacing L within the same layer, the expression for the angle difference γ of the trapezoids in two adjacent single-layer microtextures is as follows: ; Adjust the overhang angle and overhang length according to the actual working conditions. The expression for the overhang angle of the multi-layer microtexture is: ; The expression for the overhang length between adjacent layers in a multilayer microtexture is: ; In the formula, θ is the overhang angle, θ1 is the included angle of the V-groove, P is the overhang length between adjacent layers in the multilayer microtexture, and t is the layer thickness of the multilayer microtexture. S2. Based on the size of the tool substrate, one or more recesses with the same size as the tool substrate are provided on the upper surface of the printing substrate; S3. Under the protection of argon, the tool substrate is prepared in the pit obtained in step S2 by using micron-level laser powder bed melting with a layer thickness of 8~10μm. S4. Under the protection of argon, a multi-layer microtexture is prepared on the rake face of the tool substrate obtained in step S3 by using a micron-level laser powder bed melting with a layer thickness of 1~8μm based on the three-dimensional model of the multi-layer microtexture obtained in step S1. S5. The tool with multi-layer microtexture obtained in step S4 is subjected to heat treatment, and then sharpened and shaped. The heat treatment temperature is 1300℃ and the time is 1h. S6. The forming quality and functionality of the tool heat-treated in step S5 are tested using three-dimensional morphology measurement, microstructure observation and cutting performance testing.

[0007] Preferably, in step S1, the overhang angle of the multilayer microtexture causes axial deformation of the overhang portion of the multilayer microtexture ( ) and bending deformation ( The expression for ) is: ; ; In the formula, m is the dilution rate. The x-coordinate is dimensionless, representing the degree of proximity to the free end of the cantilever. E is the Young's modulus of the material, and σ is the x-coordinate. y The residual tensile stress is t, and the thickness of the printed layer is t. For axial deformation, For bending deformation; Preferably, in step S1, a trapezoid with a width D of 5~20μm, a height H of 3~15μm, and an included angle α between its two sides is set, and the lower surface of the trapezoid has a V-groove with an included angle θ1 of 150°~175°. The included angle α between the two sides of the trapezoid is greater than 0° and less than or equal to 40°.

[0008] Preferably, in step S1, the range of values ​​for the trapezoidal spacing L within the same layer is: The angle difference γ is greater than 15°.

[0009] Preferably, in step S3, the process parameters are: powder particle size of 1~10μm, scanning speed of 300~500mm / s, laser beam diameter of 15~30μm, and laser power of 40~80 W.

[0010] Preferably, in step S4, the process parameters for melting the micron-sized laser powder bed are: powder particle size of 1~10μm, scanning speed of 100~400mm / s, laser beam diameter of 15~30μm, and laser power of 10~50W.

[0011] Preferably, in the laser powder bed melting process, the heat treatment temperature is 1200℃ and the heat treatment time is 20min.

[0012] On the other hand, the present invention provides a multi-layer microtextured tool prepared by a method for preparing multi-layer microtextured tools based on micron-level laser powder bed melting, which includes a tool substrate and a multi-layer microtexture, wherein the multi-layer microtexture is located on the rake face of the tool substrate.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: To prevent structural deformation, reduced dimensional and shape accuracy caused by overhang printing of multi-layer microtextures, this invention achieves unsupported overhang printing by combining LPBF with a 150°~175° V-groove of a single-layer microtexture. The negative feedback of the overhang angle reduces the impact on dimensional and shape accuracy; it also reduces the impact of powder adhesion and printing defects caused by complete overhang, thereby improving the friction reduction and wear resistance of the cutting tool. It has good practical application value and is particularly suitable for cutting and machining difficult-to-machine materials.

[0014] To maximize the feasibility of unsupported overhanging structures, this invention designs a multi-layered microtexture with an angle difference γ greater than 15°, enhancing the overall structural stability and load-bearing capacity. This design disperses the load in a single direction, preventing overall instability of the tool under pressure. While single-layer microtextures can extend their service life by deepening grooves, thus maintaining superior tribological performance and service reliability under complex working conditions, single-layer microtextures lacking this depth-direction support are prone to collapse or peeling under cutting forces.

[0015] Because single-layer microtextures are prone to rapid failure during cutting due to wear, deformation, or blockage, resulting in the loss of their friction-reducing function, the multi-layer microtexture obtained by the method of this invention forms redundancy in structure: after the first layer of the structure wears down, the internal microtextures are exposed and continue to perform the friction-reducing function; once the existing single-layer microtextures wear down or become blocked, the friction-reducing effect is greatly reduced; while the multi-layer microtexture maintains the continuity of the friction-reducing function through the gradual exposure of the internal microtextures, reducing the decline in tool performance caused by texture failure. Therefore, the multi-layer microtexture has the advantages of excellent friction-reducing performance, resistance to microtexture damage, and improved tool life, and is suitable for cutting difficult-to-machine materials such as titanium alloys and high-strength steel, and has significant practical application value. Attached Figure Description

[0016] Figure 1 This is a flowchart of the method for preparing multi-layered microtextured cutting tools based on micron-level laser powder bed melting according to the present invention; Figure 2 This is a front view of the multi-layer microtexture in the method for preparing multi-layer microtextured tools based on micron-level laser powder bed melting in this invention; Figure 3 This is a top view of the multi-layer microtexture in the method for preparing multi-layer microtextured tools based on micron-level laser powder bed melting according to the present invention; Figure 4 This is a schematic diagram of the overhang angle of the multi-layer microtexture in the method for preparing multi-layer microtextured tools based on micron-level laser powder bed melting in this invention; Figure 5 This is a structural diagram of the multilayer microtextured tool obtained by the method of preparing multilayer microtextured tools based on micron-level laser powder bed melting according to the present invention; Figure 6 This is a partial enlarged view of the multilayer microtextured tool obtained by the method of preparing multilayer microtextured tools based on micron-level laser powder bed melting according to the present invention; Figure 7 This is an early wear diagram of the multilayer microtextured tool obtained by the method of preparing multilayer microtextured tools based on micron-level laser powder bed melting according to the present invention; Figure 8 This is a mid-term wear diagram of the multi-layer microtextured tool obtained by the method of preparing multi-layer microtextured tools based on micron-level laser powder bed melting according to the present invention; Figure 9 This is a final wear diagram of the multi-layer microtextured tool obtained by the method of preparing multi-layer microtextured tools based on micron-level laser powder bed melting according to the present invention.

[0017] Key reference numerals: Tool substrate 1, multi-layer microtexture 2. Detailed Implementation

[0018] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0019] like Figure 1 As shown, the specific implementation steps of the method for preparing multi-layered microtextured tools based on micron-level laser powder bed melting are as follows: S1. Establish a three-dimensional model of multilayer microtexture 2: Multilayer microtexture 2 is composed of superimposed single-layer microtextures. The specific process includes: like Figure 2 , Figure 3 and Figure 6 As shown, a trapezoid with a width D of 5~20μm, a height H of 3~15μm, and an included angle α between the two sides is set. The included angle α between the two sides is greater than 0° and less than or equal to 40°. In order to avoid the overhang structure that affects the processing accuracy, dimensional stability and structural reliability due to geometric abrupt changes, a V-groove of 150° to 175° is designed on the bottom contour edge of the trapezoid in each single-layer microtexture. This obtuse angle design utilizes the natural support of the powder layer to ensure that each layer can be stably formed and achieve good bonding with the lower layer.

[0020] Based on the material of the cutting tool, as well as the cutting environment and conditions, the trapezoid is translated along the direction of its short side at intervals of 10~40μm to obtain a single-layer microtexture.

[0021] To ensure the stability of the multilayer microtexture 2, adjacent single-layer microtextures are stacked 3 to 10 times with an angle difference γ to obtain the multilayer microtexture 2. Based on the overhang length P and the trapezoidal spacing L within the same layer, in this embodiment, the value range of the trapezoidal spacing L within the same layer is... The expression for the angle difference γ of the trapezoids in two adjacent single-layer microtextures is obtained: .

[0022] Specifically, to ensure the overall stability of the multilayer microtexture 2 structure, the interlayer angle difference forms an internal interlocking effect to prevent the structure from becoming unstable under pressure; and to prevent excessive overhang length, a continuous angle difference of more than 15° is set between each adjacent layer of the microtexture during slicing.

[0023] like Figure 4 As shown, in order to reduce the impact of deformation of the bottom overhang portion of the multilayer microtexture 2 on the shape accuracy of the multilayer microtexture 2, it is necessary to adjust the overhang angle and overhang length according to the actual working conditions. The expression for the overhang angle of the multilayer microtexture 2 is: .

[0024] In the LPBF process, due to the layer-by-layer manufacturing method, a step effect often appears on the surface of the overhanging structure. The expression for the overhang length between adjacent layers in the multilayer microtexture 2 is as follows: ; In the formula, θ is the overhang angle, θ1 is the included angle of the V-groove, P is the overhang length between adjacent layers in the multilayer microtexture 2, the overhang length shall not exceed 70um, and excessive overhang length will lead to structural collapse or low accuracy, and t is the layer thickness of the multilayer microtexture 2.

[0025] The overhanging portion of the multilayer microtexture 2 is equivalent to a cantilever beam. Assuming the residual tensile stress in the molten layer is equal to the yield strength of the material, the axial deformation of the cantilever beam ( ) and bending deformation ( The axial deformation of the overhanging portion of the multilayer microtexture 2 caused by the overhang angle of the multilayer microtexture 2 is proportional to tan and tan2, respectively. ) and bending deformation ( The expression for ) is: ; ; In the formula, m is the dilution rate. The x-coordinate is a dimensionless coordinate representing the degree to which the node is close to the free end of the cantilever, with a value ranging from (0,1). E is the Young's modulus of the material, and σ is the x-coordinate. y The residual tensile stress is t, and the thickness of the printed layer is t. For axial deformation, This is due to bending deformation.

[0026] S2. Based on the dimensions of the tool base 1, one or more recesses of the same size as the tool base 1 are provided on the upper surface of the printing substrate.

[0027] S3. Under the protection of argon, a tool substrate 1 is prepared in the pit obtained in step S2 by using a micron-sized laser powder bed fusion to form a layer with a thickness of 8~10μm, and then polished to remove the oxide layer. The process parameters are: powder particle size of 1~10μm, scanning speed of 300~500mm / s, laser beam diameter of 15~30μm, and laser power of 40~80 W.

[0028] On the other hand, the tool substrate 1 can also be prepared by laser powder bed melting, wherein: the powder particle size is 13~53μm, the powder layer thickness is 10~30μm, the scanning speed is 100~400mm / s, the laser beam diameter is 30~100μm, the laser power is 30~150 W, and the protective atmosphere is argon. After preparing the tool substrate 1 by laser powder bed melting, the surface of the tool substrate 1 is heat-treated and polished to remove the oxide layer. In laser powder bed melting, the heat treatment temperature is 1200℃ and the heat treatment time is 20min.

[0029] S4. Under the protection of argon gas with low oxygen content, a multi-layer microtexture 2 is prepared by melting a micron-sized laser powder bed with a layer thickness of 1~8μm on the rake face of the tool substrate 1 obtained in step S3. At this time, the powder supply cylinder in the equipment rises while the forming cylinder descends with the same micron-sized layer thickness. The scraper or roller spreads the fine metal powder evenly and flatly on the forming area. The powder particle size is 1~10μm, the scanning speed is 100~400mm / s, the laser beam diameter is 15~30μm, and the laser power is 10~50W.

[0030] S5. Separate the tool substrate 1 from the printing substrate by wire cutting, and clean the metal powder on the surface of the tool substrate 1 and inside the multi-layer microtexture 2. Heat treat the tool with multi-layer microtexture obtained in step S4 in a vacuum furnace to increase the density and hardness of the tool substrate 1, reduce residual stress, and then grind and reshape the heat-treated multi-layer anti-friction microtexture tool. The heat treatment temperature is 1300℃ and the time is 1h.

[0031] S6. Using multiple characterization methods such as three-dimensional morphology measurement, microstructure observation and cutting performance testing, the forming quality and functionality of the tool heat-treated in step S5 are tested. Finally, an integrated multi-layer microtextured tool with effective internal stress control, accurate geometry and meeting the requirements of use is obtained.

[0032] like Figure 5As shown, the multi-layer microtextured tool obtained by the method of preparing multi-layer microtextured tools based on micron-level laser powder bed melting includes a multi-layer microtexture 2 and a tool substrate 1. The multi-layer microtexture 2 is located on the rake face of the tool substrate 1. The materials of the multi-layer microtexture 2 and the tool substrate 1 are the same type or dissimilar cemented carbide with good bonding performance. In a preferred embodiment of the present invention, the types of the same type of cemented carbide material are: tungsten alloys such as W-Ti alloy, Mo-Si-B alloy and molybdenum alloy, nickel-based high-temperature alloys such as K4750 alloy and GH3536 alloy, high-entropy alloys such as AlCrFe2Ni2, high-strength aluminum alloys such as 7050 and commercial alloys such as Ni60; the dissimilar cemented carbide materials are: 316L stainless steel-18Ni300 martensitic steel, pure titanium-pure aluminum, pure tungsten-tantalum carbide, nickel-based alloy-tungsten carbide, and nickel-based alloy-yttrium oxide. The tool substrate 1 is prepared using LPBF (Laser Bed Fusion) or μ-LPBF (Micron-level Laser Bed Fusion) processes and then undergoes heat treatment and surface treatment. The multilayer microtexture 2 is fabricated on the surface of the tool substrate 1 using the μ-LPBF process. After the surface of the structural layers of the multilayer microtexture 2 wears down, the internal microtexture is exposed, achieving a friction-reducing function. This tool possesses advantages such as excellent friction-reducing performance, resistance to damage to the microtexture, and long tool life, making it particularly suitable for machining difficult-to-machine materials such as titanium alloys and high-strength steel, and demonstrating significant practical application value.

[0033] The following describes in further detail a method for preparing multilayer microtextured cutting tools based on micron-level laser powder bed melting according to the present invention, with reference to specific embodiments: In this specific embodiment, the multi-layer microtextured tool consists of a multi-layer microtexture 2 and a tool substrate 1. The specific parameters of the trapezoid that makes up the multi-layer microtexture 2 are as follows: the trapezoid width is 15μm, the trapezoid spacing within the same layer is 25μm, the height is 10μm, the included angle between the two waists is 10°, and the adjacent single-layer microtextures are arranged with alternating 75° trapezoidal grooves and 105° trapezoidal grooves. To ensure the quality of additive manufacturing, the overhang angle of the multi-layer microtexture 2 needs to be reduced, and the lower surface of the trapezoid is an inverted V-shaped structure of 170°. After the surface of the structural layer of the multi-layer microtexture 2 is worn, the internal microtexture is exposed and continues to achieve the friction reduction function.

[0034] The tool substrate 1 is made of WC-12Co and prepared using μ-LPBF technology. Specific process parameters are: powder particle size 1~10μm, powder layer thickness 10μm, scanning speed 400mm / s, laser beam diameter 22μm, laser power 60W, and argon atmosphere. After printing, the tool substrate 1 is removed from the substrate by wire cutting. The heat-treated tool substrate 1 is then ground smooth and surface impurities are removed using a grinding machine.

[0035] Using the surface of the tool substrate 1 as a base, a multilayer microtexture 2 was fabricated using μ-LPBF at low scanning speed and low layer thickness. The material of the multilayer microtexture 2 was the same as that of the tool substrate 1. Specific process parameters were: powder particle size of 1–10 μm, powder layer thickness of 3 μm, scanning speed of 400 mm / s, laser beam diameter of 22 μm, laser power of 25 W, and argon atmosphere. After printing, the tool substrate 1 was removed from the substrate by wire cutting. The tool substrate 1 was then heat-treated in a vacuum furnace at 1300 °C for 1 hour. A second surface treatment was performed to form the tool with the multilayer microtexture 2.

[0036] Secondly, the tool substrate 1 is prepared using LPBF technology, with the following specific process parameters: powder particle size of 1~10μm, powder layer thickness of 2μm, scanning speed of 300mm / s, laser beam diameter of 22μm, laser power of 40W, and argon atmosphere. After printing, the tool substrate 1 is removed from the substrate by wire cutting. The tool substrate 1 is then placed in a vacuum furnace for heat treatment at 1300℃ for 1 hour. After heat treatment, the tool substrate 1 is ground smooth and surface impurities are removed using a grinding machine.

[0037] Using the surface of the tool substrate 1 as a base, a multilayer microtexture 2 was fabricated using μ-LPBF at low scanning speed and low layer thickness. The material of the multilayer microtexture 2 was the same as that of the tool substrate 1. Specific process parameters were: powder particle size of 1–10 μm, powder layer thickness of 3 μm, scanning speed of 400 mm / s, laser beam diameter of 22 μm, laser power of 25 W, and argon atmosphere. After printing, the tool substrate 1 was placed in a vacuum furnace for heat treatment at 1200℃ for 20 min. A second surface treatment was then performed to form a tool with a multilayer microtexture.

[0038] When the first layer of microtextured tool prepared by the present invention is about to lose its anti-friction performance after participating in cutting and undergoing three stages of wear, the second layer of microtextured tool begins to participate in cutting and provides anti-friction performance, thereby improving the anti-friction performance of the tool and extending the tool life.

[0039] The wear process of the multilayer microtextured tool of the present invention is divided into three stages: Figure 7 Early wear of multi-layer microtextured tools: The surface of the tool microtexture layer is basically intact. The trapezoidal microtexture has good wear resistance and friction reduction properties, reduces cutting heat and improves the surface quality of the machined part. Figure 8 For mid-term wear of multi-layer microtextured tools: The surface layer of the tool microtexture gradually wears down, and the height of the trapezoidal microtexture is greatly reduced at this time, but it can still achieve the function of reducing friction. Figure 9The final wear stage of a multi-layered microtextured tool: After stage II wear, the surface layer of the tool's microtexture is completely worn away, and the next layer of microtexture begins to be exposed. The next layer of microtexture becomes the surface layer of the tool's microtexture and continues to perform the friction reduction function.

[0040] After the final wear stage, the condition of the main material is close to that of the early wear stage. It will periodically experience the early wear, middle wear and final wear stages until the microtexture structure layer is completely worn away and the tool is scrapped.

[0041] Traditional microtexture fabrication techniques mostly involve surface modification or subtractive processing (such as micro-EDM and mechanical engraving), which easily introduce heat-affected zones, microcracks, or interface weakening. Furthermore, they fail to address the drawbacks of rapid wear and short lifespan of microtextures, and still exhibit significant shortcomings in tool wear resistance and friction reduction performance. They also fail to effectively solve the performance problems of tools under high-load cutting conditions, limiting their application in high-performance machining. This invention utilizes μ-LPBF, which can fabricate microtextures with layer thicknesses ranging from 1 to 8 μm, achieving micron-level feature size control. Additive manufacturing allows for the integrated or stepwise fabrication of the tool substrate and multi-layer microtextures, using the same or different cemented carbide materials (such as WC-Co alloys, high-entropy alloys, etc.) to ensure interlayer bonding strength. By designing a V-groove with a trapezoidal lower surface of 150° to 175°, utilizing the natural support of the powder layer, μ-LPBF can print suspended portions without additional support structures.

[0042] Single-layer microtextures are prone to rapid failure during cutting due to wear, deformation, or blockage, resulting in the loss of their friction-reducing function. This invention employs a multi-layer microtexture design, creating a redundant system: as the first layer of microtexture on the tool surface wears down, the inner microtextures are gradually exposed, continuing to contact the machined surface and providing friction reduction. This progressive wear mechanism extends the effective life of the tool, making it particularly suitable for high-load cutting environments of difficult-to-machine materials such as titanium alloys and high-strength steel. The multi-layer microtextures, through interlayer stacking (e.g., an angle difference γ greater than 15°), enhance the overall structural stability and load-bearing capacity. This design disperses the load in a single direction, preventing overall structural instability under pressure. If single-layer microtextures achieve increased service life through methods such as deepening grooves, the lack of depth-direction support makes them prone to collapse or peeling under cutting forces.

[0043] The above embodiments are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for manufacturing a multi-layer micro-textured tool based on micron-scale laser powder bed fusion, characterized in that, The specific implementation steps are: S1, a three-dimensional model of the multi-layer micro-texture is established, specifically including: A trapezoid with a width D, a height H and two waist angles α is set, and the lower surface of the trapezoid has a V-shaped groove with an angle θ1; according to the material of the tool and the cutting environment and cutting conditions, the trapezoid is translated along the direction of the short side of the trapezoid at an interval of 10-40 μm to obtain a single-layer micro-texture; The adjacent two layers of single-layer micro-texture are stacked in an angle difference γ to obtain a multi-layer micro-texture, and according to the overhang length P and the trapezoidal interval L in the same layer, the expression of the angle difference γ of the trapezoid in the adjacent two layers of single-layer micro-texture is obtained: ； According to the actual working condition, the overhang angle and the overhang length are adjusted, and the expression of the overhang angle of the multi-layer micro-texture is: ； The expression of the overhang length between the adjacent layers in the multi-layer micro-texture is: ； In the formula, θ is the overhang angle, θ1 is the angle of the V-shaped groove, P is the overhang length between the adjacent layers in the multi-layer micro-texture, and t is the layer thickness of the multi-layer micro-texture; S2, one or more recesses with the same size as the tool base are set on the upper surface of the printing substrate according to the size of the tool base; S3, in the protection environment of argon, a micron-level laser powder bed is used to melt to prepare a tool base with a layer thickness of 8-10 μm in the recess obtained in step S2; S4, in the protection environment of argon, a micron-level laser powder bed is used to melt to prepare a multi-layer micro-texture on the rake face of the tool base obtained in step S3 with a layer thickness of 1-8 μm according to the three-dimensional model of the multi-layer micro-texture obtained in step S1; S5, the tool with the multi-layer micro-texture obtained in step S4 is heat treated, and is sharpened and profiled, the heat treatment temperature is 1300℃, and the time is 1h; S6, the forming quality and functionality of the tool heat treated in step S5 are detected by three-dimensional topography measurement, microstructure observation and cutting performance test.

2. The method for fabricating multilayer micro-textured tools based on micron-scale laser powder bed fusion according to claim 1, wherein: In step S1, the overhang angle of the multilayer microtexture causes an axial deformation ( ) and a bending deformation ( ) of the overhanging portion of the multilayer microtexture. ； ； wherein m is the dilution rate, is the dimensionless X coordinate, indicating the proximity to the free end of the cantilevered portion, E is the Young's modulus of the material, σ y is the residual tensile stress, t is the print layer thickness, is the axial deformation, is the bending deformation.

3. The method for fabricating multilayer micro-textured tools based on micron-scale laser powder bed fusion according to claim 1, wherein: In step S1, the trapezoid with a width D of 5-20 μm, a height H of 3-15 μm and two waist angles α is set, and the lower surface of the trapezoid has a V-shaped groove with an angle θ1 of 150°-175°.

4. The method for fabricating multilayer micro-textured tools based on micron-scale laser powder bed fusion according to claim 1, wherein: In step S1, the trapezoidal interval L in the same layer is in the range of , and the angle difference γ is greater than 15°.

5. The method for fabricating multilayer micro-textured tools based on micron-scale laser powder bed fusion according to claim 1, wherein: In step S3, the process parameters are: powder particle size of 1-10 μm, scanning speed of 300-500 mm / s, laser beam diameter of 15-30 μm, and laser power of 40-80 W.

6. The method for fabricating multilayer micro-textured tools based on micron-scale laser powder bed fusion according to claim 1, wherein: In step S4, the process parameters of the micron-level laser powder bed melting are: powder particle size of 1-10 μm, scanning speed of 100-400 mm / s, laser beam diameter of 15-30 μm, and laser power of 10-50 W.

7. The method for fabricating multilayer micro-textured tools based on micron-scale laser powder bed fusion according to claim 1, wherein: In the laser powder bed melting, the heat treatment temperature is 1200℃, and the heat treatment time is 20 min.

8. A multi-layer micro-textured cutting tool produced according to the method of claim 1 to 7, characterized in that: It comprises a tool base and a multi-layer micro-texture, and the multi-layer micro-texture is located on the rake face of the tool base.

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