Method and device for regulating and controlling surface microstructure of copper sheet
Through the multi-pass variable amplitude and pressure high-frequency micro forging and tangential extrusion method, the microstructure structure of the copper thin plate surface is controlled, and the problem of difficult to control the grain size and crystal orientation of the metal surface in the prior art is solved, and the crystal orientation and gradient distribution grain size of the copper thin plate surface is realized, which improves welding performance and has important industrial application value.
Patent Information
- Application Number
- CN202411780413.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-05
- Publication Date
- 2025-03-25
AI Technical Summary
The prior art is difficult to control grain size and crystal orientation on the surface of metal materials, especially to prepare microstructure structures with crystal orientation and grain sizes in gradient distribution on the surface of copper sheets.
The method of multi-pass variable amplitude and pressure high-frequency micro-forging and tangential extrusion is adopted. By performing tangential extrusion during the high-frequency micro-forging process, combined with preheating and ultrasonic softening treatment, the microstructure structure of the copper thin plate surface is regulated.
The microstructure structure with crystal orientation and grain size gradient distribution on the surface of the copper thin plate was achieved, which improved the effective thickness and welding rate of ultrasonic welded copper thin plate joints, which was of great significance to the development of the new energy vehicle industry.
Smart Images
Figure CN119681157A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of metal material surface engineering, in particular to a method and a device for regulating the surface microstructure of a copper sheet. Background Art
[0002] At present, methods for preparing a gradient nanostructure with a certain thickness and a nanocrystalline surface layer and a grain size gradually increasing along the thickness direction on the surface of metal materials by means of plastic deformation include surface mechanical grinding, surface mechanical milling, high-energy shot peening, etc. The surface gradient nanostructure can significantly reduce the nitriding temperature of the material surface, improve the hardness, wear resistance and fatigue properties of the material surface, and thus extend the service life of the material. However, according to the currently reported technologies, there is no technology that can regulate both the grain size of the metal surface and the crystal orientation.
[0003] Based on our previous research on ultrasonic welding technology, we found that if we want to improve the effective thickness and welding rate of ultrasonic welded copper sheet joints, we need to prepare {111} <110> The microstructure of the crystal orientation and the gradient distribution of grain size is an effective method. Based on this, it is necessary to develop a method for regulating the surface microstructure of copper sheets and the device used therein, which is of great significance to the development of the new energy vehicle industry. Summary of the invention
[0004] The present invention aims to provide a method and device for controlling the microstructure of a copper sheet surface, which can prepare {111} <110> A microstructure with a gradient distribution of crystal orientation and grain size.
[0005] The technical solution adopted by the present invention is: a method for regulating the surface microstructure of a copper sheet, the steps of which are as follows: The copper sheet is fixed on a movable workbench, and a tool head that can move along the Y direction is used to perform multiple passes of variable amplitude and variable pressure high-frequency micro-forging on the copper sheet; at the same time, in the above high-frequency micro-forging process, in each pass, the tool head outputs a constant amplitude and a constant pressure, and the workbench drives the copper sheet to move unidirectionally along the X direction. At this time, the tool head exerts a tangential extrusion effect on the copper sheet. Under the combined action of high-frequency micro-forging and tangential extrusion, a surface with a {111} <110> A microstructure with a gradient distribution of crystal orientation and grain size.
[0006] As a preferred solution, in the first few passes of high-frequency micro-forging and tangential extrusion, the amplitude of the tool head is 10-20 μm, the pressure is 0.2-0.25 MPa, the copper sheet is preheated and ultrasonically softened, and when the temperature of the copper sheet is greater than 80 ° C, the amplitude of the tool head is adjusted to 20-65 μm, and the pressure is adjusted to 0.25-0.8 MPa. At the same time, the increase in pressure causes the tool head to generate a large friction force with the surface of the heated and ultrasonically softened copper sheet, accelerating the rotation of the crystal orientation. After multiple unidirectional motion inductions, the surface grain orientation moves in a certain direction. <110> Direction rotation.
[0007] As a preferred solution, the workbench drives the copper sheet to move from an initial position on one side to a set position on the other side. The above process is one pass. In each pass, the tool head performs high-frequency micro-forging and tangential extrusion on the copper sheet with a constant amplitude and constant pressure. At the end of the pass, the tool head is lifted, and the workbench drives the copper sheet to automatically move to the initial position. Then, according to the set parameters, the pressure and amplitude are automatically adjusted, and the tool head falls and contacts the surface of the copper sheet to perform the next pass of high-frequency micro-forging and tangential extrusion until all set passes are completed.
[0008] As a preferred solution, the variable amplitude means that the amplitude applied by the tool head to the copper sheet in different passes is adjusted and changed in real time, and shows a trend of gradually increasing. The amplitude is 10 to 65 μm, and the vibration direction of the amplitude is perpendicular to the copper sheet.
[0009] As a preferred solution, the variable pressure means that the pressure applied by the tool head to the copper sheet in different passes is adjusted and changed in real time, and presents a trend of gradually increasing, and the pressure is 0.2-0.8 MPa.
[0010] As a preferred solution, the high-frequency micro-forging refers to the high-frequency micro-impact of the tool head on the surface of the copper sheet under the action of the applied amplitude and pressure, and the frequency of the high frequency is 20 to 40 kHz.
[0011] As a preferred solution, the workbench reciprocates along the X direction, and the speed can be adjusted in real time, the speed is 2 to 7 mm / s. Under the pressure of the tool head, a certain friction force is generated between the tool head and the surface of the moving copper sheet, and the friction force will produce a certain tangential extrusion pressure on the surface of the copper sheet.
[0012] As a preferred solution, the surface of the tool head is arc-shaped, with a width of 15-30 mm, and its material is wear-resistant alloy steel; the copper sheet refers to pure copper or copper alloy, with a thickness of 0.5 to 3.5 mm.
[0013] As a preferred solution, after the copper sheet has been subjected to multiple passes of high-frequency micro-forging and tangential extrusion, the surface of the copper sheet is cleaned with 3-5% dilute hydrochloric acid for 3-5 s to remove oxides, and then cleaned with alcohol and dried.
[0014] The present scheme also includes a device used in the method for regulating the surface microstructure of a copper sheet, including a horizontally movable workbench, the copper sheet is fixed on the workbench and moves synchronously with the workbench, and a pressure applying device, a pressure sensor, a transducer and a tool head are arranged above the copper sheet from top to bottom. The output frequency of the tool head is generated and adjusted by the transducer, and the output pressure of the tool head is controlled by the pressure sensor, and the signal is fed back to the pressure applying device to control the pressure.
[0015] The beneficial effects of the present invention are: Based on the defects of the prior art, the present invention provides a method and device for regulating the surface microstructure of a copper sheet. By optimizing the process, a smaller amplitude (10-20 μm) and pressure (0.2-0.25 MPa) are used in the first few passes of high-frequency micro-forging and tangential extrusion to preheat and ultrasonically soften the copper sheet, improve the ability of plastic deformation, and prevent cracks from forming on the surface of the copper sheet. After preheating and ultrasonic softening, when the temperature of the copper sheet is greater than 80 °C, the pressure and amplitude of the subsequent passes gradually increase. At this time, the amplitude of the tool head is adjusted to (20-65 μm) and the pressure is adjusted to (0.25-0.8 MPa) to promote the generation of dislocations and accelerate the recrystallization process to achieve the effect of grain refinement. At the same time, the increase in pressure causes a large friction force between the tool head and the surface of the copper sheet after heat and ultrasonic softening, accelerating the rotation of the crystal orientation. After multiple unidirectional motion inductions, the surface grain orientation moves in a certain direction. <110> The tool head rotates in the same direction. At the same time, the amplitude and pressure of the tool head are constant in each pass, which can ensure the uniformity of surface quality. Under the combined effect of the above strategies, the final product is a product with a gradient distribution of grain size and a {111} <110> The crystal orientation structure is of great help in improving the effective thickness and welding rate of ultrasonic welded copper sheet joints, and is of great significance to the development of the new energy vehicle industry. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0017] Figure 1 The grain size of the copper sheet surface after multiple passes of variable amplitude and variable pressure high-frequency micro-forging and tangential extrusion is a gradient distribution diagram; Figure 2 It is the inverse pole figure of the copper sheet surface after multiple passes of variable amplitude and variable pressure high-frequency micro-forging and tangential extrusion; Figure 3 Metallographic image of the copper sheet surface after multiple passes of constant amplitude variable pressure high frequency micro-forging and tangential extrusion; Figure 4 It is a schematic diagram of a multi-pass variable amplitude and variable pressure high frequency micro-forging and tangential extrusion device; Figure 4 Markings in the middle: 1 is a pressure applying device, 2 is a pressure sensor, 3 is a transducer, 4 is a tool head, 5 is a copper sheet, and 6 is a workbench; Figure 5 Metallographic image of the copper sheet surface after multiple passes of variable amplitude constant pressure high-frequency micro-forging and tangential extrusion. DETAILED DESCRIPTION
[0018] The following specific examples are given to further clearly, completely and in detail illustrate the technical solution of the present invention. This example is the best example based on the technical solution of the present invention, but the protection scope of the present invention is not limited to the following examples.
[0019] This scheme is a method for regulating the surface microstructure of a copper sheet, and the steps are as follows: The copper sheet is fixed on a movable workbench, and a tool head that can move along the Y direction is used to perform multiple passes of variable amplitude and variable pressure high-frequency micro-forging on the copper sheet; at the same time, in the above high-frequency micro-forging process, in each pass, the tool head outputs a constant amplitude and a constant pressure, and the workbench drives the copper sheet to move unidirectionally along the X direction. At this time, the tool head exerts a tangential extrusion effect on the copper sheet. Under the combined action of high-frequency micro-forging and tangential extrusion, a surface with a {111} <110> A microstructure with a gradient distribution of crystal orientation and grain size.
[0020] A device used in a method for regulating the surface microstructure of a copper sheet, comprising a horizontally movable workbench 6, a copper sheet 5 fixed on the workbench 6 and moving synchronously with the workbench 6, a pressure applying device 1, a pressure sensor 2, a transducer 3 and a tool head 4 are arranged above the copper sheet 5 from top to bottom, and the movement of the tool head 4 in the Y direction is regulated by a walking mechanism that can move up and down ( Figure 4 The displacement in this direction is carried out according to the magnitude of the applied force. The output frequency of the tool head 4 is generated and adjusted by the transducer 3. The output pressure of the tool head 4 is controlled by the pressure sensor 2, and the signal is fed back to the pressure applying device 1 to control the magnitude of the pressure.
[0021] It should be noted that: in this article, the X direction is set as the horizontal direction, that is, the moving direction of the copper sheet 5 driven by the workbench, and the Y direction is set as the vertical direction, that is, the moving direction of the tool head driven by the walking mechanism.
[0022] In the control method, the variable amplitude means that the amplitude applied by the tool head to the copper sheet in different passes is adjusted and changed in real time, and shows a trend of gradually increasing, the amplitude is 10 to 65 μm, and the vibration direction of the amplitude is perpendicular to the copper sheet; the variable pressure means that the pressure applied by the tool head to the copper sheet in different passes is adjusted and changed in real time, and shows a trend of gradually increasing, and the pressure is 0.2 to 0.8 MPa.
[0023] In the control method, the high-frequency micro-forging refers to the high-frequency micro-impact of the tool head on the surface of the copper sheet under the applied amplitude and pressure, and the frequency of the high frequency is 20 to 40 kHz; the number of the multiple passes is generally less than 20 times.
[0024] In the control method, in the first few passes of high-frequency micro-forging and tangential extrusion, the amplitude of the tool head is 10-20 μm, the pressure is 0.2-0.25 MPa, the copper sheet is preheated and ultrasonically softened, and when the temperature of the copper sheet is greater than 80°C, the amplitude of the tool head is adjusted to 20-65 μm, and the pressure is adjusted to 0.25-0.8 MPa. At the same time, the increase in pressure causes the tool head to generate a large friction force with the surface of the heated and ultrasonically softened copper sheet, accelerating the rotation of the crystal orientation. After multiple unidirectional motion inductions, the surface grain orientation moves in a certain direction. <110> Direction rotation.
[0025] In the control method, the workbench drives the copper sheet to move from an initial position on one side to a set position on the other side. The above process is one pass. In each pass, the tool head performs high-frequency micro-forging and tangential extrusion on the copper sheet with a constant amplitude and a constant pressure. At the end of the pass, the tool head is lifted, and the workbench drives the copper sheet to automatically move to the initial position. Then, according to the set parameters, the pressure and amplitude are automatically adjusted, and the tool head falls to contact the surface of the copper sheet to perform the next pass of high-frequency micro-forging and tangential extrusion until all set passes are completed.
[0026] In the control method, the workbench reciprocates along the X direction, and the speed can be adjusted in real time, the speed is 2 to 7 mm / s. Under the pressure of the tool head, a certain friction force is generated between the tool head and the surface of the moving copper sheet, and the friction force will produce a certain tangential extrusion force on the surface of the copper sheet.
[0027] In the control method, the surface of the tool head is arc-shaped, with a width of 15-30 mm, and its material is wear-resistant alloy steel; the copper sheet refers to pure copper or copper alloy, with a thickness of 0.5-3.5 mm.
[0028] In the control method, after the copper sheet is subjected to multiple high-frequency micro-forging and tangential extrusion, the surface of the copper sheet is cleaned for 3-5 seconds with 3-5% dilute hydrochloric acid to remove oxides, and then cleaned with alcohol and dried.
[0029] In the control method, the gradient distribution of grain size means that the grain size on the surface is obviously refined, and then the grain size gradually increases along the thickness direction.
[0030] Embodiment 1, A method for regulating the surface microstructure of a copper sheet is provided. A copper sheet with a thickness of 1.0 mm, a length of 120 mm, and a width of 25 mm is fixed on a workbench. The width of the tool head used is 20 mm. Then the parameters are set: the travel of the copper sheet from right to left is 20 mm, and the frequency of the tool head vibration is 20 kHz. The amplitude applied in the 1st to 3rd passes is 15 μm, the pressure is 0.25 MPa, and the travel speed of the copper sheet driven by the workbench is 3 mm / s; the amplitude applied in the 4th to 5th passes is 35 μm, the pressure is 0.45 MPa, and the travel speed is 4 mm / s; the amplitude applied in the 6th to 9th passes is 55 μm, the pressure is 0.65 MPa, and the travel speed is 5.5 mm / s. After all the passes to be applied are completed, the equipment stops moving, the copper sheet is removed, and the surface of the copper sheet is cleaned for 4 s with 4% dilute hydrochloric acid to remove oxides, and then cleaned with alcohol and dried. The surface grain size can be obtained to be 0.8 μm (see Figure 1 ), with a thickness of 34 μm. The grain size gradually transitions from 0.8 μm from the surface to the core to the original parent material grain size. The thickness of the deformation layer is 87 μm. The surface deformation layer is in the first zone (see Figure 2 ) {111} <110> Crystal orientation.
[0031] In the embodiment 1 of the invention, after multiple passes of variable amplitude and variable pressure high frequency micro-forging and tangential extrusion treatment, it can be seen that the surface grain size can be 0.8 μm (see Figure 1 ), with a thickness of 34 μm, and the grain size gradually transitions from 0.8 μm to 12 μm in the core, and the thickness of the deformation layer is 87 μm. Figure 2 It can be seen that the surface deformation layer area (see Figure 2 ) {111} <110> The crystal orientation has changed significantly compared to that of the original parent material.
[0032] Embodiment 2, A method for regulating the surface microstructure of a copper sheet is provided. A copper sheet with a thickness of 0.5 mm, a length of 120 mm, and a width of 25 mm is fixed on a workbench. The width of the tool head used is 15 mm. Then the parameters are set: the stroke of the copper sheet from left to right is 30 mm, and the frequency of the tool head vibration is 30 kHz. The amplitude applied in the 1st to 3rd passes is 10 μm, the pressure is 0.2 MPa, and the travel speed is 2 mm / s; the amplitude applied in the 4th to 5th passes is 30 μm, the pressure is 0.5 MPa, and the travel speed is 3 mm / s; the amplitude applied in the 6th to 9th passes is 50 μm, the pressure is 0.6 MPa, and the travel speed is 5 mm / s. After all the passes to be applied are completed, the equipment stops moving, the copper sheet is removed, and the surface of the copper sheet is cleaned with 3% dilute hydrochloric acid for 3 s to remove the oxide, and then cleaned with alcohol and dried.
[0033] The experiment verified that according to the method defined in this embodiment, the surface grain size can be 0.9 μm, the thickness can be 30 μm, the grain size from the surface to the inside can be gradually changed from 0.9 μm to the original parent material grain size in the core, the thickness of the deformation layer can be 60 μm, and the surface deformation layer can be {111} <110> Crystal orientation.
[0034] Embodiment 3, A method for regulating the surface microstructure of a copper sheet is proposed. A copper sheet with a thickness of 3.5 mm, a length of 120 mm, and a width of 25 mm is taken and fixed on a workbench. The width of the tool head used is 30 mm. Then the parameters are set: the stroke of the copper sheet from left to right is 30 mm, and the frequency of the tool head vibration is 40 kHz. The amplitude applied in the 1st to 4th passes was 20 μm, the pressure was 0.25 MPa, and the travel speed was 2.2 mm / s; the amplitude applied in the 5th to 6th passes was 40 μm, the pressure was 0.55 MPa, and the travel speed was 3.3 mm / s; the amplitude applied in the 7th to 10th passes was 50 μm, the pressure was 0.65 MPa, and the travel speed was 5.5 mm / s; the amplitude applied in the 11th to 13th passes was 65 μm, the pressure was 0.8 MPa, and the travel speed was 7 mm / s. After all the passes to be applied were completed, the equipment stopped moving, the copper plate was removed, and the surface of the copper plate was cleaned with 5% dilute hydrochloric acid for 5 s to remove the oxide, and then cleaned with alcohol and dried.
[0035] The experiment verified that according to the method defined in this embodiment, the surface grain size can be 0.2 μm, the thickness can be 56 μm, the grain size from the surface to the inside can be gradually changed from 0.2 μm to the original parent material grain size in the core, the thickness of the deformation layer can be 135 μm, and the surface deformation layer can be {111} <110> Crystal orientation.
[0036] Comparative Example 4 The difference between the copper sheet surface microstructure control method of this comparative example and that of Example 1 is that the multi-pass variable amplitude is adjusted to a multi-pass constant amplitude, specifically, the amplitude of the tool head is adjusted to 55 μm, specifically: Take a copper sheet with a thickness of 1.0 mm, a length of 120 mm, and a width of 25 mm. The tool head width used is 20 mm. Then set the parameters: the stroke of the copper sheet from right to left is 20 mm, and the frequency of the tool head vibration is 20 kHz. The amplitude applied in the 1st to 3rd passes is 55 μm, the pressure is 0.25 MPa, and the travel speed is 3 mm / s; the amplitude applied in the 4th to 5th passes is 55 μm, the pressure is 0.45 MPa, and the travel speed is 4 mm / s; the amplitude applied in the 6th to 9th passes is 55 μm, the pressure is 0.65 MPa, and the travel speed is 5.5 mm / s. After all the passes to be applied are completed, the equipment stops moving, the copper sheet is removed, and the surface of the copper sheet is cleaned with 4% dilute hydrochloric acid for 4 s to remove the oxide, and then cleaned with alcohol and dried. At this time, obvious cracks appear on the surface of the copper sheet (see Figure 3 ), affecting the performance.
[0037] Comparative Example 5 The difference between the copper sheet surface microstructure control method of this comparative example and that of Example 1 is that the multi-pass variable pressure is adjusted to a multi-pass constant pressure, specifically, the pressure of the tool head is adjusted to 0.6 MPa, specifically: Take a copper sheet with a thickness of 1.0 mm, a length of 120 mm, and a width of 25 mm. The tool head width is 20 mm. Then set the parameters: the stroke of the copper sheet from right to left is 20 mm, and the frequency of the tool head vibration is 20 kHz. The amplitude applied in the 1st to 3rd passes is 15 μm, the pressure is 0.6 MPa, and the travel speed is 3 mm / s; the amplitude applied in the 4th to 5th passes is 35 μm, the pressure is 0.6 MPa, and the travel speed is 4 mm / s; the amplitude applied in the 6th to 9th passes is 55 μm, the pressure is 0.6 MPa, and the travel speed is 5.5 mm / s. After all the passes to be applied are completed, the equipment stops moving, the copper sheet is removed, and the surface of the copper sheet is cleaned with 4% dilute hydrochloric acid for 4 s to remove the oxide, and then cleaned with alcohol and dried. At this time, obvious cracks appear on the surface of the copper sheet (see Figure 5 ), affecting the performance.
[0038] The parts not described in detail in the above embodiments are prior art.
[0039] It should be noted that although the present invention is described by the above embodiments, the present invention may also have other various embodiments. Without departing from the spirit and scope of the present invention, it is obvious that those skilled in the art may make various corresponding changes and deformations to the present invention, but these changes and deformations should all fall within the scope of protection of the appended claims of the present invention and their equivalents.
Claims
1. A method for regulating the surface microstructure of a copper sheet, characterized in that: Here are the steps: The copper sheet is fixed on a movable workbench, and a tool head that can move along the Y direction is used to perform multiple passes of variable amplitude and variable pressure high-frequency micro-forging on the copper sheet; at the same time, in the above high-frequency micro-forging process, in each pass, the tool head outputs a constant amplitude and a constant pressure, and the workbench drives the copper sheet to move unidirectionally along the X direction. At this time, the tool head exerts a tangential extrusion effect on the copper sheet. Under the combined action of high-frequency micro-forging and tangential extrusion, a surface with a {111} <110> A microstructure with a gradient distribution of crystal orientation and grain size.
2. The method for controlling the surface microstructure of a copper sheet according to claim 1, characterized in that: In the first few passes of high-frequency micro-forging and tangential extrusion, the amplitude of the tool head is 10-20 μm, and the pressure is 0.2-0.25 MPa. The copper sheet is preheated and ultrasonically softened. When the temperature of the copper sheet is greater than 80 °C, the amplitude of the tool head is adjusted to 20-65 μm, and the pressure is adjusted to 0.25-0.8 MPa. At the same time, the increase in pressure causes a large friction between the tool head and the surface of the heated and ultrasonically softened copper sheet, accelerating the rotation of the crystal orientation. After multiple unidirectional motion inductions, the surface grain orientation moves in a certain direction. <110> Direction rotation.
3. The method for controlling the surface microstructure of a copper sheet according to claim 1, characterized in that: The workbench drives the copper sheet to move from an initial position on one side to a set position on the other side. The above process is one pass. In each pass, the tool head performs high-frequency micro-forging and tangential extrusion on the copper sheet with a constant amplitude and constant pressure. At the end of the pass, the tool head is lifted, and the workbench drives the copper sheet to automatically move to the initial position. Then, according to the set parameters, the pressure and amplitude are automatically adjusted, and the tool head falls and contacts the surface of the copper sheet to perform the next pass of high-frequency micro-forging and tangential extrusion until all set passes are completed.
4. The method for controlling the surface microstructure of a copper sheet according to claim 1, characterized in that: The variable amplitude means that the amplitude applied by the tool head to the copper sheet in different passes is adjusted and changed in real time, and presents a trend of gradually increasing. The amplitude is 10 to 65 μm, and the vibration direction of the amplitude is perpendicular to the copper sheet.
5. The method for controlling the surface microstructure of a copper sheet according to claim 1, characterized in that: The variable pressure means that the pressure applied by the tool head to the copper sheet in different passes is adjusted and changed in real time, and presents a trend of gradually increasing, and the pressure is 0.2-0.8 MPa.
6. The method for controlling the surface microstructure of a copper sheet according to claim 1, characterized in that: The high-frequency micro-forging refers to the high-frequency micro-impact of the tool head on the surface of the copper sheet under the action of the applied amplitude and pressure, and the frequency of the high frequency is 20 to 40 kHz.
7. The method for controlling the surface microstructure of a copper sheet according to claim 1, characterized in that: The workbench reciprocates along the X direction, and the speed can be adjusted in real time, the speed is 2-7 mm / s. Under the pressure of the tool head, a certain friction force is generated between the tool head and the surface of the moving copper sheet, and the friction force will produce a certain tangential extrusion force on the surface of the copper sheet.
8. The method for controlling the surface microstructure of a copper sheet according to claim 1, characterized in that: The surface of the tool head is arc-shaped, with a width of 15-30 mm, and is made of wear-resistant alloy steel; the copper sheet refers to pure copper or copper alloy, with a thickness of 0.5-3.5 mm.
9. The method for controlling the surface microstructure of a copper sheet according to claim 1, characterized in that: After multiple passes of high-frequency micro-forging and tangential extrusion, the surface of the copper sheet is cleaned with 3-5% dilute hydrochloric acid for 3-5 s to remove oxides, and then cleaned with alcohol and dried.
10. A device for controlling the surface microstructure of a copper sheet according to any one of claims 1 to 9, characterized in that: The invention comprises a horizontally movable workbench (6), a copper sheet (5) being fixed on the workbench (6) and moving synchronously with the workbench (6), and a pressure applying device (1), a pressure sensor (2), a transducer (3) and a tool head (4) being arranged above the copper sheet (5) in order from top to bottom, wherein the output frequency of the tool head (4) is generated and adjusted by the transducer (3), and the output pressure of the tool head (4) is controlled by the pressure sensor (2), and the signal is fed back to the pressure applying device (1), thereby controlling the magnitude of the pressure.