Method for improving tool service performance by combining tool surface microstructure and pulsed magnetic field

Abstract

This invention discloses a method for improving the service performance of a cutting tool by combining surface microstructure with a pulsed magnetic field. The method includes: S1 determining the position of the array texture on the tool based on the tool's machining parameters; S2 determining the tool's placement position during magnetic field treatment based on the tool's shape; S3 selecting the intensity and number of pulsed magnetic field treatments based on the magnetic properties of the tool material; S4 calculating the pulsed magnetic field frequency based on the tool size and the pulsed magnetic field intensity; and S5 measuring the surface magnetic induction intensity of the textured area on the tool after magnetic field treatment, controlling the deviation from the theoretical saturation magnetic induction intensity of the tool material within a certain value. This invention solves problems such as poor interface lubrication and heat dissipation during tool cutting. Compared with existing technologies, this method is cleaner and faster, and has no requirements for machine tools or the machining environment, making it more suitable for modern industrial production.

Description

Technical Field

[0001] This invention belongs to the technical field of machining, specifically relating to a method for improving the service performance of a cutting tool by combining microstructures on the tool surface with a pulsed magnetic field. Background Technology

[0002] Carbide cutting tools and boron nitride superhard cutting tools are widely used in cutting. However, due to the harsh friction conditions between the tool and the chip, and between the tool and the workpiece, as well as the heat dissipation conditions, the tools are prone to rapid wear and failure during the machining process. This results in poor surface quality, insufficient precision and dimensional tolerances of the machined parts, causing serious waste of production capacity.

[0003] Current methods for improving the service performance of cutting tools during machining processes focus on two aspects:

[0004] 1. Improve the material strength of the cutting tools, such as cryogenic treatment, heat treatment, and surface shot peening.

[0005] Second, improve the heat dissipation conditions in the cutting zone of the tool, such as MQL micro-lubrication technology and liquid nitrogen cooling technology.

[0006] Cryogenic technology and heat treatment, which enhance the strength of cutting tool materials, suffer from drawbacks such as affecting tool shape accuracy and long processing cycles. Liquid nitrogen cooling technology, which improves heat dissipation in the cutting zone, is less economical during machining and places high demands on machine tools and machining conditions. Summary of the Invention

[0007] The purpose of this invention is to address the aforementioned shortcomings in the prior art by providing a method for improving the service performance of cutting tools by combining microstructures on the tool surface with pulsed magnetic fields, thereby solving the problems of poor interface lubrication conditions and poor heat dissipation during the cutting process of existing cutting tools.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A method for improving the service performance of a cutting tool by combining surface microstructure with a pulsed magnetic field includes the following steps:

[0010] S1. Determine the position of the array texture on the tool according to the tool's machining parameters;

[0011] S2. Determine the placement position of the tool during magnetic field treatment based on the shape of the tool;

[0012] S3. Select the intensity and number of pulsed magnetic field treatments based on the magnetic properties of the tool material;

[0013] S4. Calculate the pulse magnetic field frequency based on the tool size and pulse magnetic field strength;

[0014] S5. After the magnetic field treatment is completed, measure the surface magnetic induction intensity of the tool at the textured area, and determine whether the deviation between the measured magnetic induction intensity and the theoretical saturation magnetic induction intensity of the tool material is within the threshold range. If it is within the threshold range, end the magnetic field treatment; if it is not within the threshold range, return to step S2 until the threshold range is met.

[0015] Furthermore, step S1 specifically includes:

[0016] After ultrasonic cleaning of the tool with anhydrous ethanol, an array of grooves is formed at a distance of 150-200 μm from the main cutting edge, the secondary cutting edge, and the tool tip.

[0017] Furthermore, the array texture spacing is 150-200 μm, the texture width is 80-100 μm, and the width-to-depth ratio of the texture is 0.4-0.5;

[0018] The texture forms include circular array texture and straight groove array texture, wherein the starting and ending segments of the straight groove array texture are arc-shaped.

[0019] Furthermore, step S2 specifically includes:

[0020] The cutting tool is magnetized with a pulsed magnetic field to ensure that the axis of the geometric center of the cutting tool coincides with the axis of the geometric center of the pulsed magnetic field device during the magnetization process.

[0021] Furthermore, for single-head cutting tools, ensure that the line connecting the center point of the cutting edge and the midpoint of the tool geometry lies on the centerline of the central region of the magnetic processing equipment;

[0022] For double-ended cutting tools, ensure that the intersection of the lines connecting the midpoints of the cutting edges and the line connecting the center point of the tool's geometry is on the center line of the central region of the magnetic field processing equipment.

[0023] Furthermore, step S3 specifically includes:

[0024] For cemented carbide cutting tools, the intensity of the pulsed magnetic field is 1.5T to 2.5T, and the number of pulsed magnetic field treatments is 15 to 30.

[0025] Diamond and cubic boron nitride superhard cutting tools, tools bonded with metal binder Co, with pulsed magnetic field strength of 1.0T to 2.5T, and pulsed magnetic field treatment times of 20 to 40 times;

[0026] For cutting tools bonded with metal-ceramic binders, the pulsed magnetic field strength is 0.5T to 1.5T, and the number of pulsed magnetic field treatments is 25 to 45.

[0027] For coated cutting tools, the pulsed magnetic field strength is 1.0T to 2.5T, and the number of pulsed magnetic field treatments is 25 to 40.

[0028] Furthermore, step S4 specifically includes:

[0029] The frequency of the pulsed magnetic field is calculated using the skin effect:

[0030]

[0031] δ=0.6x

[0032] Where δ is the penetration depth, σ is the electrical conductivity, u is the magnetic permeability, f is the frequency of the pulse magnetic field, and x is the longest dimension in the three-dimensional dimensions of the tool.

[0033] The method for improving tool performance by combining tool surface microstructure with pulsed magnetic field provided by this invention has the following beneficial effects:

[0034] This invention combines the microstructure of the tool surface with a pulsed magnetic field to improve the tool's service performance. Moreover, this invention is green, fast, and convenient. In industrial processing, it can significantly reduce the additional economic costs associated with tool modification technology and greatly improve the performance ceiling of low-end tools, which are the mainstream in the tool market.

[0035] This invention texturizes the tool surface and then treats it with a magnetic field. Based on improving the tool lubrication conditions through the physical structure of the texturing, the residual magnetism on the tool surface after magnetic field treatment reduces the liquid wetting angle during the cutting process. A smaller liquid wetting angle has a larger fluid diffusion area, thereby further improving the lubrication and heat exchange advantages of the tool during the cutting process.

[0036] This invention utilizes a pulsed magnetic field to treat the cutting tool, thereby uniformly strengthening the tool as a whole. This avoids damage to the tool caused by impact and fatigue during machining due to uneven material properties caused by localized strengthening. Attached Figure Description

[0037] Figure 1 This is an example diagram of the surface texture of a cutting tool.

[0038] Figure 2 This is a schematic diagram showing the placement of the cutting tool during pulsed magnetic field treatment.

[0039] Figure 3 The experimental measurement results show the effect of surface remanence on the wetting angle of cutting fluids with different concentrations.

[0040] The components include: 1. Pulsed magnetic field processing cavity; 2. Magnetic induction coil; 3. Cutting tool. Detailed Implementation

[0041] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0042] Example 1

[0043] refer to Figure 1 and Figure 2 This embodiment describes a method for improving the service performance of a cutting tool by combining surface microstructure with a pulsed magnetic field. The invention utilizes a combination of magnetic field treatment and surface microtexturing to improve interface lubrication during cutting, thereby enhancing the service performance of the cutting tool, reducing wear, and extending its service life. Compared to existing cutting tool strengthening technologies, this method is faster, more convenient, and more environmentally friendly. The specific steps include:

[0044] Step S1: Determine the position of the array texture on tool 3 according to the machining parameters of tool 3. This step determines the specific position of the array texture on tool 3 based on the cutting parameters of tool 3, which is more conducive to preventing stress concentration during machining due to unreasonable positioning of the array texture. Specifically, it includes:

[0045] Tool 3 cutting parameters, such as depth of cut, feed rate, etc.;

[0046] When the specific location is determined, after ultrasonic cleaning of the tool 3 with anhydrous ethanol, an array of grooves is formed at a position 150-200um away from the main cutting edge, the secondary cutting edge and the tool tip.

[0047] Specifically, the finishing tool 3 with a small depth of cut performs an array texture at a distance of 150 μm from the main cutting edge, the secondary cutting edge, and the tool tip. As the precision of the workpiece processed by the tool 3 decreases, the distance of the entire array texture increases in the range of 150 μm-200 μm. At the same time, the spacing of the array texture is 150-200 μm, the width of the texture is 80-100 μm, and the width-to-depth ratio of the texture is 0.4-0.5.

[0048] The textures are mainly of two types: circular array texture and straight groove array texture. The starting and ending sections of the straight groove array texture are arc-shaped, which can effectively prevent stress concentration.

[0049] Step S2, Reference Figure 2 Based on the shape of the tool 3, the placement position of the tool 3 during magnetic field treatment is determined, that is, the position of the tool 3 in the pulsed magnetic field treatment cavity 1 is determined. The pulsed magnetic field treatment cavity 1 is equipped with magnetic induction coils 2. This step is used to strengthen the tool 3 in the magnetic field, and specifically includes:

[0050] The tool 3 is magnetized by a pulsed magnetic field to ensure that the axis of the geometric center of the tool 3 coincides with the axis of the geometric center of the pulsed magnetic field device during the magnetization process;

[0051] Specifically, the position of the tool 3 in the magnetic field is determined according to the shape of the different tools 3;

[0052] For a single-head cutting tool 3, ensure that the line connecting the center point of the cutting edge of the tool 3 and the midpoint of the geometry of the tool 3 is on the centerline of the central region of the magnetic processing equipment.

[0053] For the double-ended cutting tool 3, ensure that the intersection of the lines connecting the midpoints of the cutting edges of tool 3 and the line connecting the center point of the geometric shape of tool 3 are on the center line of the central region of the magnetic field processing equipment.

[0054] In this embodiment, the tool 3 is placed in a magnetic field in a specific geometric state. Electrons in the material of the tool 3 interact with the magnetic field through the magnetic moment caused by the spin angular momentum and orbital angular momentum or the cyclotron motion caused by the Lorentz force, thereby strengthening the tool 3 in the magnetic field.

[0055] Step S3: Select the intensity and number of pulse magnetic field treatments based on the magnetic properties of the tool material 3. In this embodiment, different tool materials 3 correspond to different pulse treatment intensities and numbers, specifically including:

[0056] The magnetic field strength and number of magnetization cycles required for modifying tools made of different materials, such as cemented carbide, superhard tools, and coated tools, which are commonly used in machining, are also different.

[0057] Specifically: For cemented carbide cutting tools 3, since the material of cutting tool 3 itself can easily reach magnetic saturation, and the stronger the magnetic field, the more orderly the magnetic domains are arranged, the intensity of the pulsed magnetic field is in the range of 1.5T to 2.5T, and the number of pulsed magnetic field treatments can be slightly less, in the range of 15 to 30 times;

[0058] For diamond, cubic boron nitride and other superhard cutting tools 3, and cutting tools 3 bonded with metal binders such as Co, the intensity of the pulsed magnetic field is 1.0T to 2.5T, and the number of treatments is 20 to 40.

[0059] For cutting tools 3 bonded with cermet binders (TiN, TiC, etc.), the pulsed magnetic field strength is between 0.5T and 1.5T, and the number of treatments is between 25 and 45. For coated cutting tools 3, the pulsed magnetic field strength is between 1.0T and 2.5T, and the number of treatments is between 25 and 40.

[0060] Step S4: Calculate the pulse magnetic field frequency based on the tool 3 dimensions and the pulse magnetic field strength. This specifically includes:

[0061] The pulse magnetic field frequency was calculated using the skin effect.

[0062]

[0063] δ=0.6x

[0064] Where δ is the penetration depth (mm), σ is the electrical conductivity, u is the magnetic permeability, f is the pulse magnetic field frequency, and x is the longest dimension in the three-dimensional dimensions of the tool.

[0065] In the above formula, the permeability u can be calculated using the permeability formula:

[0066]

[0067] Where B is the magnetic induction intensity and H is the magnetic field intensity, the magnetic permeability can be calculated from this; that is, the magnetic permeability of the material of the cutting tool 3 is calculated based on the magnitude of the magnetic field intensity in step S3.

[0068] To ensure that the tool 3 is fully reinforced, the penetration depth should be greater than half of the longest dimension x in the three-dimensional dimensions of the tool 3, and we take δ = 0.6x;

[0069] By substituting the known penetration depth δ, electrical conductivity σ, and magnetic permeability u into the above formula, the pulse magnetic field frequency f can be calculated, thereby determining the magnetic field frequency processed by tool 3 under different magnetic field intensities.

[0070] Step S5: Measure the surface magnetic induction intensity of the tool 3 after magnetic field treatment, and determine whether the deviation between the measured magnetic induction intensity and the theoretical saturation magnetic induction intensity of the tool 3 material is within the threshold range. If it is within the threshold range, end the magnetic field treatment; if it is not within the threshold range, return to step S2 until the threshold range is met.

[0071] Specifically, after processing the tool 3, the magnetic induction intensity at the cutting edge of the tool 3 is measured using a Tesla meter; ensure that the deviation of the magnetic induction intensity at the cutting edge of each tool 3 after magnetic field treatment does not exceed ±0.5mT. For tools 3 with insufficient surface magnetic induction intensity, they are subjected to magnetic field treatment again and their magnetic induction intensity is measured again until they meet the requirements.

[0072] Similar magnetic induction intensity can ensure the stable performance of tool 3 when machining titanium alloy after magnetic treatment. This is based on the understanding that during the cutting process, tiny chips rotate at high speed under the action of the residual magnetism of tool 3, cutting magnetic field lines and generating an induced electromotive force that offsets part of the cutting heat.

[0073] refer to Figure 3This invention texturizes the surface of the cutting tool 3 and then applies magnetic field treatment. Based on improving the lubrication conditions of the cutting tool 3 through the physical structure of the texturing, the residual magnetism on the surface of the cutting tool 3 after magnetic field treatment reduces the liquid wetting angle during the cutting process. A smaller liquid wetting angle has a larger fluid diffusion area, thereby further enhancing the lubrication and heat exchange advantages of the cutting tool 3 during the cutting process. This invention uses a combination of magnetic field treatment and surface microtexturing to improve the interface lubrication of the cutting tool 3 during cutting, thereby improving the service performance of the cutting tool 3, reducing the wear of the cutting tool 3, and extending the service life of the cutting tool 3. Compared with existing cutting tool strengthening technologies, this method is faster, more convenient, and more environmentally friendly.

[0074] Although specific embodiments of the invention have been described in detail with reference to the accompanying drawings, this should not be construed as limiting the scope of protection of this patent. Various modifications and variations that can be made by a person skilled in the art without inventive effort within the scope described in the claims still fall within the scope of protection of this patent.

Claims

1. A method for improving the service performance of a cutting tool by combining surface microstructure with a pulsed magnetic field, characterized in that, Includes the following steps: S1. Determine the position of the array texture on the tool according to the tool's machining parameters; S2. Determine the placement position of the tool during magnetic field treatment based on the shape of the tool; S3. Select the intensity and number of pulsed magnetic field treatments based on the magnetic properties of the tool material; S4. Calculate the pulse magnetic field frequency based on the tool size and pulse magnetic field strength; S5. After the magnetic field treatment is completed, the surface magnetic induction intensity of the tool is measured at the textured area. It is determined whether the deviation between the measured magnetic induction intensity and the theoretical saturation magnetic induction intensity of the tool material is within the threshold range. If it is within the threshold range, the magnetic field treatment ends; if it is not within the threshold range, the process returns to step S2 until the threshold range is met. Step S1 specifically includes: After ultrasonic cleaning of the cutting tool with anhydrous ethanol, an array of grooves is formed at a distance of 150-200 μm from the main cutting edge, the secondary cutting edge, and the tool tip. For finishing tools with small depth of cut, an array of textures is formed at a distance of 150 μm from the main cutting edge, the secondary cutting edge, and the tool tip. As the precision of the parts being machined by the tool decreases, the distance of the entire texture increases within a certain range. The array texture spacing is 150-200 μm, the texture width is 80-100 μm, and the width-to-depth ratio of the texture is 0.4-0.

5. The texture forms include circular array texture and straight groove array texture, wherein the starting and ending segments of the straight groove array texture are arc-shaped; Step S3 specifically includes: For cemented carbide cutting tools, the intensity of the pulsed magnetic field is 1.5T to 2.5T, and the number of pulsed magnetic field treatments is 15 to 30. Diamond and cubic boron nitride superhard cutting tools, tools bonded with metal binder Co, with pulsed magnetic field strength of 1.0T to 2.5T, and pulsed magnetic field treatment times of 20 to 40 times; For cutting tools bonded with metal-ceramic binders, the pulsed magnetic field strength is 0.5T to 1.5T, and the number of pulsed magnetic field treatments is 25 to 45. For coated cutting tools, the pulsed magnetic field strength is 1.0T to 2.5T, and the number of pulsed magnetic field treatments is 25 to 40. Step S4 specifically includes: The frequency of the pulsed magnetic field is calculated using the skin effect: δ=0.6x Where δ is the penetration depth, σ is the electrical conductivity, u is the magnetic permeability, f is the pulse magnetic field frequency, and x is the longest dimension in the three-dimensional dimensions of the tool.

2. The method for improving tool service performance by combining tool surface microstructure with pulsed magnetic field according to claim 1, characterized in that, Step S2 specifically includes: The cutting tool is magnetized with a pulsed magnetic field to ensure that the axis of the geometric center of the cutting tool coincides with the axis of the geometric center of the pulsed magnetic field device during the magnetization process.

3. The method for improving tool service performance by combining tool surface microstructure with pulsed magnetic field according to claim 2, characterized in that: For single-head cutting tools, ensure that the line connecting the center point of the cutting edge and the midpoint of the tool geometry lies on the centerline of the central region of the magnetic processing equipment. For double-ended cutting tools, ensure that the intersection of the lines connecting the midpoints of the cutting edges and the line connecting the center point of the tool's geometry is on the centerline of the central region of the magnetic field processing equipment.

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