A bionic swallowtail-shaped micro-textured cutting tool and its preparation method

Abstract

The present invention discloses a bionic swallowtail-shaped micro-textured tool and a preparation method thereof, belonging to the technical field of metal cutting tools. The preparation method is based on a cemented carbide tool substrate, and combines the structural advantages of the swallowtail structure in reducing frictional resistance and accelerating the flow of gas and liquid. On this basis, a corresponding functional tool is prepared by machining a bionic swallowtail-shaped groove and surface texture. The designed tool groove is used to discharge chips and store and convey cutting fluid; the surface texture is used to reduce the frictional force between the chip and the tool during cutting and promote the discharge of chips, thereby reducing the cutting force, improving the tool life and processing efficiency. Compared with the prior art, based on the bionic principle, the present invention combines the tool groove and the surface texture to design and prepare a functional tool, achieving the functional requirements of improving the heat resistance and wear resistance of the tool, prolonging the tool life, reducing the production and processing cost, and realizing green processing, and meeting the production and processing needs.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal cutting tools, and relates to a design and preparation method of a bionic dovetail-shaped micro-textured tool suitable for metal processing. Background Art

[0002] Metal cutting processing based on various machine tools has an extremely important position in industrial manufacturing. It can be said that the efficiency of metal cutting processing directly affects the efficiency and production capacity of the entire manufacturing industry. Cutting tools are factors that directly affect the efficiency of metal cutting processing. Generally speaking, if a tool has good wear resistance, high heat resistance, and a long cutting life, it will have lower processing costs and higher processing efficiency. Therefore, there is a very broad prospect for designing and preparing wear-resistant and long-life tools that are suitable for a variety of metal cutting occasions and various cutting scenarios.

[0003] In addition, the development of production technology is an important reason for promoting the improvement of human living standards. However, the earth's ecological environment is also deteriorating rapidly. Adapting production and processing to environmental protection and realizing green processing have become an increasingly concerned topic in the manufacturing industry. During the metal cutting process, the large consumption of tool materials, the extensive use of cutting fluids, and the greater power output of machine tools are all important reasons affecting the development of green processing. Therefore, how to reduce the wear of tools during metal cutting processing and extend their service life, and how to reduce the generation of waste liquid, waste gas, waste residue, and noise, etc., to achieve green processing are technical problems that need to be solved urgently by those skilled in the art.

[0004] The Chinese patent application with the publication number CN113492220A and the publication date of October 12, 2021 discloses a micro-textured tool for workpiece processing, including a tool tip and a rake face. A plurality of micro-structures with different sizes are processed and arranged on the rake face, and the sizes of the plurality of micro-structures are arranged in a gradient. The micro-structure includes a groove, and a protrusion is arranged around the opening of the groove; although this tool utilizes the grooves and protrusions of the micro-texture to store lubricating fluid and improve the lubrication effect, it is only achieved through a few grooves with edge protrusions, and the effect is not good. Moreover, this tool only has the function of storing lubricating fluid and improving the cooling effect, and the means are single and cannot meet the requirements of high-precision processing at the present stage. Summary of the Invention

[0005] The purpose of the present invention is to provide a design and preparation method of a bionic dovetail-shaped micro-textured tool, which is used to reduce the tool wear during metal cutting processing, extend the tool life, and at the same time reduce the processing energy consumption and the use of cutting fluid, so as to achieve energy conservation and emission reduction.

[0006] To achieve the above purpose, on the one hand, the present invention provides a bionic dovetail-shaped micro-textured tool, including: a tool substrate;

[0007] A dovetail groove structure provided on the tool substrate, the groove structure including a plurality of elliptical grooves distributed along the cutting edge extension direction, and the plurality of elliptical grooves being connected by long trapezoidal straight grooves to form a through groove;

[0008] A dovetail surface texture adjacent to the groove structure, the surface texture including a plurality of dovetail grooves arranged along the cutting edge extension direction and a straight groove along the cutting edge extension direction and close to the cutting edge side.

[0009] As a preferred technical solution, the groove structure is distributed on the rake face of the tool.

[0010] As a preferred technical solution, the areas of the plurality of elliptical grooves are different, and the elliptical groove closer to the tool tip has a smaller area.

[0011] As a preferred technical solution, the groove structure is in the shape of a dovetail, the center lines of the two dovetails are parallel to the main and secondary cutting edges, the dovetail angle is 50 - 60°, and the fillet radius at the intersection is 300 - 500 μm.

[0012] As a preferred technical solution, each dovetail of the groove structure is integrally in the shape of a straight long trapezoid, the trapezoid base angle is 75 - 85°, with a slope, the tool tip is low and the tail end is high, the straight line length is 6 - 8 mm, and the transition arc radius between the groove structure and the rake face is 50 - 100 μm.

[0013] As a preferred technical solution, the center distance of each elliptical groove distributed along the center lines of the two dovetails is 2 mm, the major axis of the ellipse is 0.5 - 3 mm, the minor axis is 0.2 - 1.5 mm, and the depth of the through groove formed by the elliptical groove and the long trapezoidal straight groove is 200 - 300 μm.

[0014] As a preferred technical solution, the surface texture is provided at the tool tip, the length of each dovetail groove is 100 - 150 μm, the tip angle is 35 - 45°, the tail angle is 70 - 80°, and the distance between adjacent tips is 150 - 250 μm.

[0015] As a preferred technical solution, the maximum width of the straight groove is 50 μm, the length is 1.5 - 2 mm, the distance between the center line of the straight groove and the cutting edge is 100 μm; the depths of the straight groove and the dovetail groove are both 25 - 50 μm, and the distance between their center lines is 70 μm.

[0016] On the other hand, the present invention also provides a preparation method for a bionic dovetail micro-textured tool, including the following steps:

[0017] Step 1: Laser process a dovetail groove structure in the bionic dovetail micro-textured tool described in any one of the above technical solutions on the tool substrate;

[0018] Step 2: Laser process the surface texture on the tool substrate to form the bionic dovetail-shaped micro-texture tool according to any one of the above technical solutions.

[0019] The present invention has achieved the following technical effects compared with the prior art:

[0020] Based on the bionics principle, the present invention combines the tool groove shape and the surface texture on the tool substrate, and improves the heat resistance and wear resistance of the tool during the cutting process through different means, prolongs the tool life, and reduces the use of cutting fluid to meet the requirements of green machining. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0022] Figure 1 It is a schematic diagram of the overall structure of a bionic dovetail-shaped micro-texture tool provided by an embodiment of the present invention;

[0023] Figure 2 It is a schematic diagram of the detailed structure of the tool tip of a bionic dovetail-shaped micro-texture tool provided by an embodiment of the present invention;

[0024] Figure 3 It is a schematic diagram of the overall structure of a bionic dovetail-shaped micro-texture tool provided by another embodiment of the present invention;

[0025] Description of reference numerals: 100 - overall tool; 1 - tool substrate; 11 - tool tip; 12 - cutting edge; 13 - rake face; 2 - groove structure; 21 - long trapezoidal straight groove; 22 - elliptical groove; 3 - surface texture; 31 - dovetail-shaped groove; 32 - straight groove; 4 - liquid-repellent groove DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in this embodiment. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0027] The purpose of the present invention is to provide a tool structure and preparation method suitable for metal cutting processing that can achieve green cutting, which is used to reduce the wear of the tool during metal cutting processing, reduce the use of cutting fluid, and prolong its service life.

[0028] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] As Figure 1 and Figure 2 shown, the present invention provides a bionic dovetail-shaped micro-textured tool 100 suitable for metal cutting, including a tool substrate 1, a groove structure 2, and a surface texture 3.

[0030] The model of the tool substrate 1 can be selected according to actual needs. For example, the tool substrate 1 with the model of CCMT09T308 or CNMG120408. In this embodiment, the substrate material of the cutting tool is a YG6 cemented carbide tool, and the main components are tungsten carbide (WC) and cobalt (Co) element binders. The YG6 grade indicates that the content of Co element inside is about 6%.

[0031] The groove structure 2 is formed by laser processing. Its function is to store the cutting fluid during the cutting process and transport the cutting fluid to the cutting part, thereby reducing the usage amount of the cutting fluid and lowering the cutting temperature. At the same time, the elliptical groove can appropriately store part of the chips during the cutting process, accelerate the fracture of the chips and the separation of the chips from the tool, and improve the tool life and reduce the processing loss. The groove structure 2 as a whole presents a dovetail shape, and in high-speed machining, the aerodynamic friction reduction and lift effect of the dovetail shape can be utilized to prompt the chips to leave the tool surface faster, thereby better extending the tool life.

[0032] The surface texture 3 has the functions of chip breaking and transporting the cutting fluid. The straight groove 32 near the cutting edge can make the cutting fluid flow better through the tool surface. The continuously arranged dovetail-shaped grooves 31 can break the chips during machining. The dovetail structure can accelerate the chips to leave the tool surface by generating gas lift during high-speed cutting, thereby reducing the cutting temperature and improving the tool life.

[0033] In this embodiment, the groove structure 2 and the surface texture 3 are combined on the tool substrate 1. By different means, the heat resistance and wear resistance of the tool during the cutting process are improved, the tool life is extended, the processing energy consumption and the usage amount of the cutting fluid are reduced, so as to meet the processing needs of metal cutting and achieve the goal of energy conservation, emission reduction, and green processing.

[0034] Furthermore, the groove structure 2 of this embodiment is distributed on the rake face of the tool. Its overall structural shape is similar to a dovetail. The center lines of the two dovetails are parallel to the main and secondary cutting edges. The dovetail angle is 50-60°, and the fillet radius at the intersection is 300-500 μm. Each dovetail of the groove structure 2 is in the shape of a straight trapezoid as a whole. The bottom angle of the trapezoid is 75-85°, with a certain slope, being lower at the tip and higher at the tail end. The straight-line length is 6-8 mm. The transition arc radius between the groove structure 2 and the rake face 13 is 50-100 μm. The center distance of each elliptical groove 21 distributed along the center lines of the two dovetails of the groove structure 2 is 2 mm. The major axis of the ellipse is 0.5-3 mm, and the minor axis is 0.2-1.5 mm. The structural depth formed by the elliptical groove 21 and the long trapezoidal straight groove 22 is 200-300 μm.

[0035] In this embodiment, the surface texture 3 is composed of two parts and is distributed at the position of the tool tip 11. One of its structural components is a dovetail groove 31 arranged linearly. The length of each dovetail groove 31 is 100-150 μm, the tip angle is 35-45°, the tail angle is 70-80°, and the distance between adjacent tips is 150-250 μm. The other is a straight groove 32 outside the dovetail groove 31. The maximum width of the straight groove 32 is 50 μm, the length is 1.2-2 mm, and the distance between the center line of the straight groove 32 and the main and secondary cutting edges is 100 μm. The depths of both the straight groove 32 and the dovetail groove 31 are 50 μm, and the center distance between their center lines is 70 μm.

[0036] Furthermore, in order to achieve the mutual cooperation between the groove structure 2 and the surface texture 3 during the machining process, so as to improve the cutting efficiency, the center distance between the dovetail groove 31 and the groove structure 2 in this embodiment is 50 μm. During cutting, the chip flowing on the rake face 13 of the tool can flow obliquely along the dovetail groove 31 towards the groove structure 2, and the chip is stored in the groove structure 2. The elliptical structure 21 of the groove structure 2 has the function of breaking chips. At the same time, during cutting, excessive cutting fluid can also be stored in the groove structure 2 through this structure. The stored cutting fluid can be slowly supplied to the tool tip through the combined action of the slope inside the groove structure 2 and the liquid drainage structure 3, thereby stabilizing the cutting process and ensuring the machining quality.

[0037] This embodiment also provides a preparation method for a bionic dovetail-shaped micro-texture tool suitable for metal cutting, which is used to prepare the above-mentioned bionic dovetail-shaped micro-texture tool 100 suitable for metal cutting, and includes the following steps:

[0038] A dovetail groove structure 2 with the functions of storing and conveying fluid is machined on the tool substrate 1, and then the dovetail surface texture 2 is machined at the tool tip position; or the dovetail surface texture 3 is first machined on the tool substrate 1, and then the dovetail groove structure 2 for storing and conveying fluid is machined on the surface of the tool substrate 1 by laser processing technology, so that the groove structure 2 and the surface texture 3 are matched.

[0039] Among them, both the groove structure 2 and the surface texture 3 can be processed by picosecond laser according to relevant parameters. After the above steps are completed, the tool can be further processed according to the actual processing situation.

[0040] In another embodiment, as Figure 3 shown, a plurality of triangular liquid drainage grooves 4 are formed in the groove structure 2. The liquid drainage grooves 4 are arranged along the extension direction of the cutting edge 12, and the liquid drainage grooves 4 can make the cutting fluid converge more at the tool tip to play a role in cooling and lubrication.

[0041] The preparation method of the bionic dovetail micro-texture tool for metal cutting under different processing environments in the present embodiment will be described below in conjunction with two specific embodiments: Embodiment 1

[0042] As Figure 1 shown, this embodiment provides a preparation method of a bionic dovetail micro-texture tool for metal cutting under low-speed dry cutting conditions, which is used to prepare the above-mentioned bionic dovetail surface micro-texture tool 100 for metal cutting (as Figure 1 , Figure 2 shown), including the following steps:

[0043] S1. Select a tool substrate 1 with the model CCMT09T308, and the material of the tool substrate 1 is WC cemented carbide.

[0044] S2. Ultrasonically clean the tool substrate 1 in a mixed solution of acetone and absolute ethanol for 20 - 30 minutes for subsequent laser processing.

[0045] S3. On the surface of the rake face 13, use picosecond laser to directly write and machine a long trapezoidal straight groove 21 in the groove structure 2 at a position parallel to and with a center distance of 300 μm from the cutting edge, so as to form a dovetail groove. Subsequently, convert the laser parameters on the long trapezoidal straight groove 21 and machine elliptical grooves 21 according to the parameter that the center distance of each elliptical groove is 2 mm; the two dovetail center lines of the dovetail texture are respectively parallel to the main and secondary cutting edges, and the included angle is 60°.

[0046] S4. Using the laser direct writing method, picosecond lasers are used to individually machine dovetail-shaped surface textures 31 at positions 50 μm away from the center of the groove structure 2. The shape parameters are as follows: the length of each dovetail structure is 150 μm, the apex angle is 45°, the tail angle is 80°, the spacing is 250 μm, the center line of the dovetail groove 31 is parallel to the cutting edge, and the number depends on the size of the blade. In this embodiment, there are 6; then, the laser parameters are adjusted to machine a straight groove 32 at a position 70 μm away from the center of the dovetail groove 31 and parallel to the cutting edge. The width of the straight groove 32 is 40 μm and the length is 2 mm; the depths of both the straight groove 32 and the dovetail groove 31 are 40 μm.

[0047] S5. For cutting metals under dry cutting conditions, in order to better solve the problem of poor lubricity between the tool and the workpiece under dry cutting conditions, a layer of MoS2 solid lubricant with an average thickness of 10 μm is attached inside the dovetail groove 31. Its density is 4.8 - 5.0 g / cm 3 , the particle size reaches 325 - 2500 mesh, the micro-particle hardness is 1 - 1.5, and the friction coefficient is 0.05 - 0.1. The solid lubricant MoS2 is located inside the surface texture 3 and is used for lubrication and friction reduction during cutting. It can directly form a lubricating film on the tool surface and the chip, reducing the friction force between the chip and the rake face 13 of the tool, thereby reducing tool wear, improving the surface quality after machining, and extending the tool life. In addition, MoS2 is obtained through chemical purification and comprehensive reaction, and its pH value is 7 - 8, slightly alkaline. It covers the surface of the friction material, can protect other materials, prevent them from being oxidized, especially make other materials not easy to fall off, and enhance the adhesion force, thus playing a role in protecting the tool; in Example 1, the magnetron sputtering coating method is used to deposit MoS2 inside the surface texture 3 on the surface of the already machined tool substrate.

[0048] In this embodiment, for the case of metal cutting under low-speed dry cutting conditions, the tool groove structure 2 can use the dovetail-shaped structure to provide lift during high-speed machining to accelerate chip evacuation during dry cutting, thereby reducing the cutting temperature; the surface texture 3 can reduce the tool-chip contact area, and the solid lubricant MoS2 is located inside the surface texture 3, which can directly form a lubricating film on the tool surface and the chip, reducing the friction force between the chip and the rake face of the tool, thereby reducing tool wear, improving the surface quality after machining, and extending the tool life.

[0049] Example 2

[0050] As Figure 3As shown in the figure, this embodiment provides a preparation method for a bionic dovetail-shaped micro-textured tool for metal cutting under high-speed lubrication conditions, which is used to prepare the above-mentioned bionic dovetail-shaped surface micro-textured tool 100 for metal cutting. For the case under high-speed lubrication conditions, in this embodiment, a liquid-repellent groove 4 is machined at the bottom of the dovetail groove structure 2, which is located inside the groove of the dovetail groove structure. It is composed of 7 triangular grooves with a vertex angle of 30° and a height of 0.8 mm. The center line of each triangle coincides with the center line of the groove structure. The distance between each triangle is 1 mm, and the depth of the groove is 20 μm.

[0051] Specifically, it includes the following steps:

[0052] S1. Select a tool substrate 1 of model CCMT09T308, and the material of the tool substrate 1 is WC cemented carbide.

[0053] S2. Ultrasonically clean the tool substrate 1 in a mixed solution of acetone and absolute ethanol for 20 - 30 minutes to prepare for subsequent laser processing.

[0054] S3. On the surface of the rake face 13, use picosecond laser to laser direct write and machine a long trapezoidal groove 21 in the groove structure 2 at a position parallel to and with a center distance of 400 μm from the cutting edge, so as to form a dovetail groove shape. Subsequently, convert the laser parameters on the long trapezoidal straight groove 21 and machine elliptical grooves 22 according to the parameter of a center distance of 2 mm for each elliptical groove; The two dovetail center lines of the dovetail texture are respectively parallel to the main and secondary cutting edges, and the included angle is 55°.

[0055] S4. Adopt the laser direct writing method, and use picosecond laser to machine dovetail grooves 31 one by one at a position with a center distance of 40 μm from the groove structure 2. Its shape parameters are as follows: the length of each dovetail structure is 130 μm, the tip angle is 40°, the tail angle is 75°, the spacing is 225 μm, and the center line of the dovetail groove 31 is parallel to the cutting edge. The number depends on the size of the blade. In this embodiment, it is 6; Subsequently, adjust the laser parameters and machine a straight groove 32 at a position with a center distance of 60 μm from the dovetail groove 31 and parallel to the cutting edge. According to the processing characteristics under high-speed lubrication, set its maximum width to 50 μm and length to 5 mm here; The depths of both the straight groove 32 and the dovetail groove 31 are 30 μm.

[0056] S5. Adopt the method of laser liquid-phase processing to immerse the workpiece in a 0.8% mass fraction of fluorosilane solution, the solute of which is heptadecafluorodecyltrimethoxysilane and the solvent is 8015A fluorosolvent, and then use high-energy laser to machine the liquid-repellent groove 4.

[0057] In this Embodiment 2, for the machining conditions with cooling and lubrication during cutting, the tool groove structure 2 can supply cutting fluid to the cutting area by using the dovetail-shaped structure during cutting, reducing the usage amount of the cutting fluid. At the same time, the dovetail-shaped structure also provides lift force under high-speed machining to accelerate the chip discharge, thus greatly reducing the cutting temperature; the liquid drainage groove 4 can make more cutting fluid converge at the tool tip to play the roles of cooling and lubrication; the surface texture 3 is used to store chips and transport cutting fluid. The straight groove 32 near the cutting edge can make the cutting fluid flow better through the tool surface, and the linearly arranged dovetail groove recesses 31 can promote chip breakage, reduce the interaction between the tool and the chip, and improve the tool life.

[0058] In this specification, specific examples are used to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A bionic swallowtail-shaped micro-textured cutting tool, characterized in that, Comprising: A tool substrate; A dovetail-shaped groove structure located on the tool substrate, and the structure of the groove structure is located on the rake face of the tool; the dovetail shape, that is, the shape similar to the tail of a swift, is specifically characterized in that two lines intersect at an acute angle to form a "V" shape. The groove structure includes a plurality of elliptical grooves distributed along the cutting edge extension direction, and the plurality of elliptical grooves are connected by long trapezoidal straight grooves to form a through groove; A dovetail-shaped surface texture adjacent to the groove structure, and the surface texture is arranged at the tool tip; the surface texture includes a plurality of dovetail-shaped grooves arranged along the cutting edge extension direction, and a straight groove along the cutting edge extension direction and close to one side of the cutting edge.

2. The bionic swallowtail-shaped micro-textured cutting tool according to claim 1, characterized in that, The groove structure is in a dovetail shape, the center lines of the two dovetails are parallel to the main and secondary cutting edges, the dovetail angle is 50-60°, and the fillet radius at the intersection is 300-500 μm; specifically, each dovetail of the groove structure is integrally trapezoidal, the trapezoidal base angle is 75-85°, with a slope, the tool tip is low and the tail end is high, the straight line length is 6-8 mm, and the transition arc radius between the groove structure and the rake face is 50-100 μm.

3. The bionic swallowtail-shaped micro-textured cutting tool according to claim 1, characterized in that, The length of each dovetail-shaped groove is 100-150 μm, the tip angle is 35-45°, the tail angle is 70-80°, and the distance between adjacent tips is 150-250 μm.

4. The bionic swallowtail-shaped micro-textured cutting tool according to claim 1 or 2, characterized in that, The areas of the plurality of elliptical grooves are different, and the elliptical groove closer to the tool tip has a smaller area.

5. The bionic swallowtail-shaped micro-textured cutting tool according to claim 4, characterized in that, The center distance of each elliptical groove distributed along the center lines of the two dovetails is 2 mm, the major axis of the ellipse is 0.5-3 mm, the minor axis is 0.2-1.5 mm, and the depth of the through groove formed by the elliptical groove and the long trapezoidal straight groove is 200-300 μm.

6. The bionic swallowtail-shaped micro-textured cutting tool according to claim 1 or 3, characterized in that, The maximum width of the straight groove is 50 μm, the length is 1.5-2 mm, and the distance between the center line of the straight groove and the cutting edge is 100 μm; the depths of the straight groove and the dovetail-shaped groove texture are both 25-50 μm, and the distance between their center lines is 70 μm.

7. A preparation method of a bionic swallowtail-shaped micro-textured cutting tool, characterized in that, Including the following steps: Step 1: Laser process a dovetail-shaped groove structure in the tool substrate in the bionic dovetail-shaped micro-textured tool as described in any one of claims 1-6; Step 2: Laser process a surface texture in the tool substrate in the bionic dovetail-shaped micro-textured tool as described in any one of claims 1-6.

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