A copper-based metal surface multi-wavelength laser synchronous processing device and polishing method

Abstract

The application discloses a kind of copper-based metal surface multi-wavelength laser synchronous processing device and polishing method, belong to metal surface pretreatment technical field, by introducing infrared laser light path and ultraviolet laser light path, realize a kind of multi-wavelength laser synchronous collaborative polishing method.The surface roughness of copper alloy material is reduced by double laser beam collaborative polishing, on the one hand, the absorption rate of copper alloy to infrared laser can be increased by the synergistic effect of ultraviolet and infrared laser, and the workpiece surface is reconstructed twice, to improve the surface quality after polishing, on the other hand, the surface polishing of workpiece with certain curvature is completed by combining the robustness of continuous laser and the controllable movement of four-axis substrate platform, and by adjusting the processing parameters of infrared laser and ultraviolet laser and the motion parameters of substrate platform, synchronous, large-scale processing is realized, and the adaptability of workpiece processing material is improved.

Description

Technical Field

[0001] This invention belongs to the field of metal surface pretreatment technology, specifically relating to a multi-wavelength laser synchronous processing device and polishing method for copper-based metal surfaces. Background Technology

[0002] With the development of the times, industrial manufacturing has increasingly higher requirements for the surface roughness of materials. Laser polishing technology, as a new type of polishing technology, features high polishing precision and fast processing speed. Using a highly focused laser beam to polish different material surfaces makes it easier to meet the requirements for reducing roughness in modern manufacturing processes. Laser polishing is a non-contact polishing technology, which is very attractive from an industrial application perspective because it can automate the polishing process, improve the processing efficiency of material surfaces, and eliminate the need for mechanical abrasives or surface polishing tools. This polishing technology can not only obtain non-spherical and non-rotational optically polished surfaces, but also polish surfaces with complex morphologies, which is very difficult with traditional polishing methods. Laser polishing technology has gained popularity among researchers due to its higher polishing efficiency and faster speed for different material surfaces, and therefore, it is increasingly being applied to various material surfaces.

[0003] Polishing of copper-based metals is currently mostly done through electrolytic polishing and chemical polishing. Lasers used to polish copper-based metal workpieces typically employ shorter wavelengths. For example, brass alloys are most commonly polished using electrochemical methods. However, the following factors often lead to unsatisfactory polishing results:

[0004] 1. Due to low current density or uneven distribution of electric field lines, dark spot-like defects in the shape of circles or ovals may appear on the surface of the workpiece after electrochemical polishing. In severe cases, they may form gray-black circular or oval marks, affecting the surface quality of the workpiece after polishing.

[0005] 2. During electrochemical polishing, gas streaks may be generated due to gas overflow. As the gas rises along the workpiece surface, it continuously agitates the surface, accelerating its dissolution. This is especially true for horizontally placed workpieces, where the gas accumulates at one point and rises continuously, producing noticeable gas streaks. The higher the current density during electrochemical polishing, the more gas is generated, and the greater the tendency to form gas streak defects.

[0006] 3. Electropolishing cannot remove or conceal deep scratches, pits, or other surface defects, nor can it remove non-metallic inclusions in the metal. Chemical polishing generally produces a slightly lower surface quality than electropolishing, and the solution is more difficult to adjust and regenerate. Furthermore, the polishing process can release harmful gases, causing environmental pollution.

[0007] Copper and its alloys have low absorption rates during laser melting, with an absorption rate of only 2% to 3% for high-power lasers at a wavelength of 1050 nm, making them difficult to polish using ordinary infrared lasers. For these reasons, the surface polishing efficiency of brass alloy workpieces is low, the polishing quality is difficult to control, and environmental pollution is severe, hindering automated production. Summary of the Invention

[0008] This invention provides a multi-wavelength laser synchronous processing device and polishing method for copper-based metal surfaces, which improves the surface quality of alloy workpieces, effectively reduces surface roughness, has very high processing efficiency, and introduces no impurities after polishing. The entire processing process is pollution-free, low-carbon, and environmentally friendly, effectively solving the defects of copper alloys being difficult to process with long-wavelength lasers and having unsatisfactory polishing effects.

[0009] To achieve the above objectives, the present invention provides a multi-wavelength laser synchronous processing device for copper-based metal surfaces. The device includes a base, an argon-sealed chamber on which a three-axis motion guide rail is installed. A rotary disk is mounted on the three-axis motion guide rail, and a work panel is mounted on the rotary disk. A fixture for holding the workpiece to be processed is mounted on the work panel. A first column and a second column are installed outside the sealed chamber, and an infrared processing module and an ultraviolet processing module are respectively mounted on the first and second columns.

[0010] Furthermore, the three-axis motion guide rail includes a vertical motion guide rail, on which a horizontal motion guide rail is mounted via a vertical motion guide rail slider; a vertical motion guide rail is slidably mounted on the horizontal motion guide rail, and a rotary disk is slidably mounted on the vertical motion guide rail.

[0011] Furthermore, the infrared processing module includes an infrared fiber laser, a collimator, an infrared laser beam expander, an infrared laser adapter neck, an infrared laser galvanometer, and an infrared laser field lens connected in sequence; a first support plate is installed on the first column, the infrared fiber laser, collimator, and infrared laser beam expander are fixedly connected to the first support plate by a latch, the infrared laser adapter neck is fixedly connected to the end of the first support plate, and the infrared laser galvanometer is fixedly connected to the other end of the infrared laser adapter neck.

[0012] Furthermore, the ultraviolet processing module includes an ultraviolet fiber laser, an ultraviolet laser beam expander, an ultraviolet laser adapter, an ultraviolet laser galvanometer, and an ultraviolet laser field lens connected in sequence; a second support plate is installed on the second column, the ultraviolet fiber laser is fixed on the second support plate, the ultraviolet laser beam expander is threadedly connected to the ultraviolet fiber laser, one end of the ultraviolet laser adapter is fixedly connected to the ultraviolet fiber laser, and the other end is fixedly connected to the ultraviolet laser galvanometer.

[0013] Furthermore, the ultraviolet laser beam expander is installed inside the ultraviolet laser adapter neck; the ultraviolet laser galvanometer and the ultraviolet laser field mirror are connected by an adapter ring thread.

[0014] Furthermore, the ultraviolet laser adapter neck and the infrared laser adapter neck are installed inside the sealed chamber, and the ultraviolet laser adapter neck and the infrared laser adapter neck are sealed to the chamber wall with sealant.

[0015] Furthermore, pressure sensors are installed on the side walls of the sealed chamber, and oxygen concentration sensors are installed on the top.

[0016] The method for simultaneous polishing of copper-based metal surfaces using a multi-wavelength laser synchronous processing device, as described above, includes the following steps:

[0017] Step 1: Adjust the angle of the infrared laser galvanometer so that the processing area of ​​the infrared fiber laser coincides with the processing area of ​​the ultraviolet laser.

[0018] Step 2: Adjust the three-axis motion guide rails so that the working plane is located at the focal plane of the ultraviolet laser;

[0019] Step 3: Install the workpiece in the fixture and fix it in place;

[0020] Step 4: Adjust the height of the workpiece by adjusting the three-axis motion guide rail so that the workpiece surface is located at the focal plane of the two lasers, and determine the relative position of the processing area on the workpiece surface by using the red light contour preview function in the infrared fiber laser.

[0021] Step 5: Close the hatch of the sealed chamber and fill the sealed chamber with protective gas;

[0022] Step 6: When the oxygen concentration drops to the specified range, turn off the inflation switch and maintain an argon atmosphere inside the chamber;

[0023] Step 7: According to the set parameters, use an infrared fiber laser pulse mode to perform laser rough polishing on the workpiece surface to remove substances on the workpiece surface that may affect the surface quality after polishing.

[0024] Step 8: Process the workpiece according to the set laser scanning speed, wherein the infrared fiber laser adopts continuous mode and the ultraviolet laser adopts pulse mode;

[0025] Step 9: Adjust the position of the workpiece in the horizontal direction, and process the areas other than the workpiece surface and the galvanometer scanning area according to Step 7;

[0026] Step 10: By adjusting the angle of the rotary table and the position of the three-axis motion guide, process the area with curvature on the surface of the workpiece as in Step 7.

[0027] Furthermore, in step 7, the power of the infrared fiber laser is less than the power of the infrared fiber laser in step 8.

[0028] Furthermore, the galvanometer angle of the infrared fiber laser in step 1 is determined by the following formula:

[0029]

[0030] In the formula, θ is the rotation angle of the infrared laser galvanometer, f is the focal length of the infrared laser field lens, and d is the horizontal distance between the centers of the infrared laser and the ultraviolet laser galvanometer.

[0031] Furthermore, in step 4, the relationship between the defocus amount and the light spot is determined by the following formula:

[0032]

[0033]

[0034] In the formula, D is the spot diameter, D0 is the waist spot diameter, and z is the defocusing amount. R λ is the Rayleigh length, and λ is the laser wavelength.

[0035] Furthermore, in step 8, the average energy density of the infrared continuous laser beam is determined by the following formula:

[0036]

[0037] In the formula, P is the infrared laser power, and t is the time the infrared laser spot stays on the sample surface. In continuous laser, t = D / v f A is the area of ​​the light spot, v f For scanning speed;

[0038] The scanning speed of an infrared fiber laser beam in continuous mode and the scanning speed of an ultraviolet laser beam are determined by the following formulas:

[0039]

[0040]

[0041]

[0042] In the formula, y is the distance from O to O1, where O is the intersection of the extended line of the infrared laser galvanometer center point and the plane containing the workpiece surface, O1 is the intersection of the left line of the processing scanning range and the plane containing the workpiece surface, z is the distance from O to O2, where O2 is the intersection of the right line of the processing scanning range and the plane containing the workpiece surface, a is the angle between the extended line of the infrared laser galvanometer center point and the galvanometer scanning range, d is the distance from the infrared laser galvanometer center point to the workpiece surface, and α is the tilt angle of the infrared laser galvanometer. In the continuous mode of the infrared fiber laser, a = arctan(s). h / f), where s h Let f be half the side length of the processing area set at the focal plane of the infrared fiber laser, f be the distance from the infrared laser galvanometer to the focal plane, y+z be the length of the processing area at the focal plane of the infrared fiber laser mapped onto the workpiece surface, v1 be the scanning speed of the ultraviolet laser beam, v2 be the scanning speed of the infrared fiber laser beam, and d be half the side length of the processing area set at the focal plane of the infrared fiber laser. f This is the actual side length at the focal plane of the infrared fiber laser.

[0043] Furthermore, the rotation angle of the rotating disk in step 11 is determined by the following formula:

[0044]

[0045] In the formula, β is the rotation angle of the rotating disk, x1 and x2 are the positions of two points on the surface after being projected onto the reference coordinates, and y is the function curve obtained by fitting after scanning the meridian of the surface;

[0046] The distance the vertical motion guide slider moves is determined by the following formula:

[0047]

[0048] In the formula, l is the vertical movement distance of the guide rail, and x2-x1 is the distance between two points on the curved surface projected onto the reference coordinates. At that time, the rotating disk rotates clockwise. At that time, the rotating disk rotates counterclockwise.

[0049] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0050] The multi-wavelength laser synchronous processing device described in this invention can significantly improve the surface quality of polished copper alloy workpieces compared to traditional single-laser beam processing and polishing systems. When processing with a single laser beam, if only an infrared laser is used, the absorption rate of copper alloys is only 2% to 3%, as copper alloys are highly reflective materials. The remaining laser energy is reflected, which not only reduces the efficiency of surface polishing and increases polishing costs, but also easily causes surface damage when using a high-power laser. Simultaneously, when the processing area under the laser galvanometer is exposed to laser radiation, most of the remaining energy is reflected back into the galvanometer. If there is no isolator in the laser beam path, this will damage the laser, affecting its normal function and lifespan. If an ultraviolet laser is used to process the surface of copper-based alloy metals, although copper alloys have a high absorption rate, impurities are easily precipitated. Zinc in copper alloys is a reactive element, and during processing, molten pool fluctuations easily occur, affecting the surface quality after polishing. Furthermore, substances such as internal carbon impurities that do not easily absorb ultraviolet laser energy will precipitate to the surface with the molten pool fluctuations during processing, affecting the surface roughness after polishing. This invention employs multi-wavelength laser synchronous processing. An infrared processing module emits an infrared laser that obliquely irradiates the workpiece surface. Due to the robustness of continuous lasers, the polishing effect is roughly the same within a certain processing range. This ensures both polishing quality and prevents damage to the laser from reflected laser light. Ultraviolet laser is then applied at very short intervals for synergistic polishing. Because copper-based alloys have good thermal conductivity, the molten pool generated by the ultraviolet laser affects the applied infrared laser, increasing its absorption rate and performing secondary reconstruction on the copper-based alloy metal surface at appropriate laser power. This secondary reconstruction includes crack repair and surface micro-melting, thereby improving the surface quality after polishing.

[0051] Furthermore, the three-axis motion guide and the rotary disk form a four-axis base plate platform. The continuous laser robustness and controllable movement of the four-axis base plate platform can complete the surface polishing of workpieces with a certain curvature.

[0052] Furthermore, by adjusting the processing parameters of relevant infrared and ultraviolet lasers and the motion parameters of the controllable moving four-axis base plate platform, synchronous, large-format processing can be achieved, improving the adaptability of workpiece processing materials.

[0053] Furthermore, the chamber pressure detection sensor is glued to the side wall of the sealed chamber, and the oxygen concentration sensor is glued to the top of the sealed chamber, so as to ensure that when using the exhaust method for argon protection, all parts of the sealed chamber can reach the specified argon concentration range.

[0054] Furthermore, for workpieces with special requirements for curvature at the corner edges, the corresponding processing parameters of ultraviolet laser polishing can be adjusted to reduce the heat-affected zone while ensuring surface roughness, thereby achieving material removal without affecting the curvature of the corner. By changing the number of polishing processes, a certain surface depth can be achieved.

[0055] Furthermore, the beam expander of the ultraviolet fiber laser is installed inside the adapter neck to save installation space and ensure concentricity.

[0056] Furthermore, the chamber pressure detection sensor is glued to the side wall of the sealed chamber, and the oxygen concentration sensor is glued to the top of the sealed chamber to ensure that all parts of the sealed chamber can reach the specified argon concentration range when using the exhaust method for argon protection.

[0057] Compared to traditional single-laser-beam processing and polishing methods, the method described in this invention can significantly improve the surface quality of copper alloy workpieces after polishing. It avoids the damage to the laser, the reduction in surface polishing efficiency, and the increase in polishing costs caused by the large energy loss and reflection of infrared lasers alone. At the same time, it can also suppress the molten pool fluctuation and impurity precipitation during ultraviolet laser processing alone. Through the synergistic effect of ultraviolet and infrared lasers, the absorption rate of copper alloys to infrared lasers is increased, and the surface is reconstructed at an appropriate laser power, thereby improving the surface quality after polishing.

[0058] Furthermore, the power of the infrared laser is less than that of the infrared laser in step 8 because the laser ablation threshold of surface impurities is relatively low, and they can be removed using lower energy. Attached Figure Description

[0059] Figure 1 This is an isometric view of the processing device of the present invention;

[0060] Figure 2 This is a right-side cross-sectional view of the processing apparatus of the present invention;

[0061] Figure 3 This is a left-side cross-sectional view of the processing device of the present invention;

[0062] Figure 4 This is a front cross-sectional view of the processing apparatus of the present invention;

[0063] Figure 5 Schematic diagram of a rhomboid brass alloy workpiece;

[0064] Figure 6 The original surface roughness distribution diagram of the workpiece (5×0.25mm);

[0065] Figure 7 The surface roughness distribution of the workpiece after multi-wavelength laser synergistic polishing (5×0.25mm);

[0066] Figure 8 This is a logarithmic distribution diagram of roughness frequency before and after polishing;

[0067] Figure 9 This is a schematic diagram showing the relationship between the scanning speeds of infrared lasers and ultraviolet lasers.

[0068] In the attached diagram: 1. Base; 2. First column; 3. Argon gas filling switch; 4. Sealed chamber clamp; 5. Exhaust switch; 6. Chamber pressure detection sensor; 7. Vertical motion guide rail motor; 8. Sealed chamber; 9. Transmission worm gear; 10. Vertical motion guide rail slider; 11. Vertical motion guide rail; 12. Horizontal motion guide rail; 13. Ultraviolet laser galvanometer; 14. Infrared laser galvanometer; 15. Ultraviolet laser field lens; 16. Infrared laser field lens; 17. Vertical motion guide rail slider; 18. Clamp; 19. 20. L-shaped flat plate; 21. Working panel; 22. Screw; 23. Rotary disk; 24. Vertical motion guide rail; 25. Horizontal motion guide rail slider; 26. Infrared laser adapter neck; 27. Infrared laser beam expander; 28. Collimator; 29. ​​Infrared fiber laser; 30. Ultraviolet laser; 31. Ultraviolet laser beam expander; 32. Vertical motion guide rail motor; 33. Oxygen concentration sensor; 34. Horizontal motion guide rail motor; 35. Second column; 36. Workpiece. Detailed Implementation

[0069] To make the objectives and technical solutions of this invention clearer and easier to understand, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0070] Reference Figures 1 to 4 A multi-wavelength laser synchronous processing device for polishing copper-based alloy surfaces includes a rectangular base 1 with a sufficiently large area to accommodate a first column 2 and a sealed chamber 8. The sealed chamber 8 is mounted on the base 1 and secured around its perimeter by clamps 4, which are bolted to the base 1. The sealed chamber 8 contains a chamber pressure sensor 6 and an oxygen concentration sensor 33, while the outer wall of the chamber is equipped with an argon gas filling switch 3 and an exhaust switch 5. The chamber pressure sensor 6 is bonded to the side wall of the sealed chamber 8, and the oxygen concentration sensor 33 is bonded to the top of the sealed chamber 8.

[0071] The sealed chamber 8 has a base equipped with a vertical motion guide rail 11, a vertical motion guide rail 23, a rotating disk 22, and an L-shaped plate 19. The vertical motion guide rail 11 is fixed to the base with bolts and mounted on the vertical motion guide rail slider 10. The vertical motion guide rail slider 10 is fixed to the horizontal motion guide rail 12 with bolts. The vertical motion guide rail slider 10 is threadedly connected to the transmission worm gear 9, so that the horizontal motion guide rail 12 can slide along the vertical motion guide rail 11. The transmission worm gear 9 is connected to the power output shaft of the vertical motion guide rail motor 7. The power is provided by the vertical motion guide rail motor 7 and transmitted by the transmission worm gear 9. A vertical motion guide rail 23 is mounted on a horizontal motion guide rail slider 24. The horizontal motion guide rail slider 24 and the vertical motion guide rail 23 are fixedly connected by bolts. The power for the horizontal motion guide rail slider 24 and the horizontal motion guide rail motor 34 is provided by the horizontal motion guide rail motor. The horizontal motion guide rail slider 24 is threadedly connected to the horizontal motion guide rail transmission worm gear, which transmits power. The horizontal motion guide rail transmission worm gear is connected to the power output shaft of the horizontal motion guide rail motor 34. A rotating disk 22 is mounted on a vertical motion guide rail slider 17. The vertical motion guide rail slider 17 and the rotating disk 22 are fixedly connected by bolts. The vertical motion guide rail slider 17 is threadedly connected to the vertical motion transmission worm gear, which is connected to the power output shaft of the vertical motion guide rail motor 32. This allows the rotating disk 22 to slide along the vertical motion guide rail 23. The power for the vertical motion transmission worm gear is provided by the vertical motion guide rail motor 32. The L-shaped plate 19 is fixedly connected to the rotating disk 22 via a screw 21, allowing the L-shaped plate 19 to rotate clockwise or counterclockwise around the vertical motion guide rail 11. The L-shaped plate 19 has a replaceable work panel 20, which is bolted to the L-shaped plate 19. The work panel 20 has a workpiece clamp 18, which is adjustable and bolted to the work panel 20 at the bottom. The workpiece clamp 18 is adjustable, and its maximum working size should be larger than the maximum size of the workpiece. The workpiece is placed horizontally on the work panel 20 and clamped by the workpiece clamp 18. The three-axis motion guide rail has a movement speed of up to 200 mm / s and a working accuracy of ±0.02 mm. Because it uses a 57 closed-loop stepper motor with a torque of up to 3 Nm, the vertical load capacity can reach 30 kg, and the horizontal load capacity can reach 20 kg.

[0072] A first column 2 and a second column 35 are fixed to both sides of the base 1. A first support plate is bolted to the first column 2. An infrared laser optical path is mounted on the left side of the first support plate. The direction of the infrared laser optical path is perpendicular to the first column 2 and parallel to the base 1. An infrared fiber laser 28, a collimator 27, an infrared laser beam expander 26, an infrared laser adapter neck 25, an infrared laser galvanometer 14, and an infrared laser field lens 16 are installed sequentially in the optical path. The infrared fiber laser 28, collimator 27, and infrared laser beam expander 26 are fixedly connected to the support plate with latches. One end of the infrared laser adapter neck 25 is fixedly connected to the end of the irregularly shaped plate, and the infrared fiber galvanometer 14 is fixedly connected to the other end of the infrared laser adapter neck 25 with bolts. The infrared laser galvanometer 14 and the infrared laser field lens 16 are connected by an adapter ring threaded connection. The infrared fiber laser 28 has a power of 100 watts and can operate in both continuous and pulsed modes. The pulsed laser uses the MOPA mode, with adjustable pulse width and frequency, and an output spot size of 6mm. The infrared laser beam expander 26 is an adjustable magnification beam expander, adjustable from 1x to 1.3x. The infrared laser galvanometer 14 is connected to the optical path via an infrared laser adapter 25. An infrared laser field lens 16 is mounted below the infrared laser galvanometer 14. The acceptable spot size for the infrared laser galvanometer 14 is 6-10mm. It is connected to a control card via two rotary motors, and the laser beam direction is controlled by a computer. The infrared laser field lens 16 has a working area of ​​110mm × 110mm and a focal length of 160mm. The infrared laser galvanometer 14 is rotated counterclockwise by 30° to 45° before being connected to the optical path.

[0073] An ultraviolet laser optical path is mounted on a second irregularly shaped plate on the second column 35 on the right side of the base 1. The direction of the ultraviolet laser optical path is perpendicular to the second column 35 and parallel to the base 1. The ultraviolet fiber laser 29, ultraviolet laser adapter neck 30, ultraviolet laser beam expander 31, ultraviolet laser galvanometer 13, and ultraviolet laser field lens 15 are installed sequentially in the optical path. The ultraviolet fiber laser 29 is an integrated ultraviolet fiber laser. The ultraviolet fiber laser 29 is bolted to the second irregularly shaped plate, the ultraviolet laser beam expander 31 is threaded to the ultraviolet fiber laser 29, the ultraviolet laser adapter neck 30 is bolted to the ultraviolet fiber laser 29, the galvanometer 13 is bolted to the other end of the ultraviolet laser adapter neck 30, and the ultraviolet laser galvanometer 13 is threaded to the ultraviolet laser field lens 15 via an adapter ring. The ultraviolet laser beam expander 31 is installed inside the ultraviolet laser adapter neck 30, ensuring concentricity. The ultraviolet laser beam expander 31 is a fixed-magnification beam expander with a magnification of 6x. This invention uses an integrated ultraviolet laser, which, compared to traditional single-laser-head lasers, is easier to install, occupies less space, and offers better lifespan and laser output stability. The ultraviolet fiber laser 29 has a power of 20 watts and an output spot size of 1.5mm. An ultraviolet laser field lens 15 is installed below the ultraviolet laser galvanometer 13. The ultraviolet laser galvanometer 13 can accept spot sizes of 6-10mm. It is controlled by a computer via a control card connected to two rotary motors. The ultraviolet laser field lens 15 has a working area of ​​150mm × 150mm and a focal length of 170mm. The ultraviolet laser galvanometer 13 is parallel to the plane of the base 1. The infrared laser optical path and the ultraviolet laser optical path are installed into the chamber through the slots provided on the wall of the sealed chamber 8 and sealed. The scanning range of the two galvanometers should completely cover the area where the working panel 20 is located.

[0074] The second support plate has the same structure as the first support plate.

[0075] The ultraviolet laser adapter neck 30 and the infrared laser adapter neck 25 are installed inside the sealed chamber 8, and the ultraviolet laser adapter neck 30 and the infrared laser adapter neck 25 are sealed to the chamber wall of the sealed chamber 8 with sealant.

[0076] Reference Figures 5 to 9 Taking the processing of the upper surface of a 20mm×10mm×10mm brass alloy triangular prism workpiece 36 as an example, a multi-wavelength laser synchronous polishing method for copper-based alloy surfaces includes the following steps:

[0077] Step 1: Open the sealed chamber door and clamp the workpiece using the workpiece clamp 18 to ensure that the workpiece does not slide relative to the work panel 20 during the movement of the three-axis motion guide rail and the rotary disk 22.

[0078] Step 2: Adjust the angle of the infrared laser galvanometer 14. The angle of the ultraviolet laser galvanometer 13 does not need to be adjusted, so that the processing area of ​​the infrared fiber laser 28 and the processing area of ​​the ultraviolet fiber laser 29 overlap and are within the range of the workpiece surface.

[0079] The rotation angle of the infrared fiber laser galvanometer mirror 14 is determined by the following formula:

[0080]

[0081] In the formula, θ is the rotation angle of the infrared laser galvanometer 14, f is the focal length of the infrared laser field lens 16, and d is the horizontal distance between the center of the infrared laser 14 and the center of the ultraviolet laser galvanometer 13.

[0082] Step 3: Adjust the position of the workpiece 36 by adjusting the positions of the vertical motion guide slider 10, the horizontal motion guide slider 24 and the vertical motion guide slider 17. The upper surface of the workpiece 36 is located at the focal plane of the ultraviolet fiber laser 29 by changing the laser defocusing amount and the spot.

[0083] The relationship between defocusing amount and spot size is determined by the following formula:

[0084]

[0085]

[0086] In the formula, D is the spot diameter, D0 is the waist spot diameter, and z is the defocusing amount. R λ is the Rayleigh length, and λ is the laser wavelength.

[0087] Step 4: Close the door of the sealed chamber 8 and turn on the argon filling switch 3 to fill the sealed chamber with protective gas;

[0088] Step 5: When the value displayed by the oxygen concentration sensor 33 drops to the specified range, turn off the argon filling switch 3 and the exhaust switch 5 to maintain an argon atmosphere in the sealed chamber 8; in this embodiment, the specified range is below 100 ppm.

[0089] Step 6: Using an infrared fiber laser in 28-pulse mode, set its output power, laser scanning speed, pulse width, frequency and other parameters to perform laser rough polishing on the upper surface of the workpiece to remove the oxide layer and other substances on the workpiece surface that may affect the surface quality after polishing.

[0090] Step 7: Switch the infrared fiber laser 28 from pulse mode back to continuous mode. Set the scanning speed of the two lasers according to the relationship between the scanning speed of the infrared laser and the ultraviolet laser. At the same time, set the output power and other parameters of the two lasers, such as the infrared fiber laser 28 and the ultraviolet fiber laser 29, so that the average energy density of the laser beams emitted by the infrared fiber laser 28 and the ultraviolet fiber laser 29 reaches the target value. Under this target value, the surface of the workpiece can be reconstructed in a secondary manner. First, turn on the infrared fiber laser 28. Within a certain time range, which is no more than 1ms, turn on the ultraviolet fiber laser 29. The time control is completed by the computer.

[0091] In this step, the target value E1 of the average energy density of the infrared laser beam is determined by the following formula:

[0092]

[0093] In the formula, P1 is the power of the infrared fiber laser 28, and t1 is the time the infrared laser spot stays on the sample surface. In continuous laser, t1 = D1 / v f1 A1 is the area of ​​the infrared laser spot. In Gaussian lasers, A1 = πD1 2 / 4, v f1 D1 represents the scanning speed of the external fiber laser and D1 represents the diameter of the infrared laser spot.

[0094] In this step, the target value E2 of the average energy density of the ultraviolet laser beam is determined by the following formula:

[0095]

[0096] In the formula, P2 is the power of the ultraviolet fiber laser 29, which is one-twenty-fifth to one-thirtieth of the power of the infrared fiber laser 28; t2 is the time the ultraviolet laser spot stays on the sample surface, and in continuous laser, t2 = D2 / v f2 A2 is the area of ​​the ultraviolet laser spot. In Gaussian lasers, A2 = πD / D2. 2 / 4, v f D2 represents the scanning speed, and D2 represents the diameter of the ultraviolet laser spot.

[0097] Reference Figure 9 The scanning speed of the infrared laser 28 beam in continuous mode and the scanning speed of the ultraviolet pulsed laser 29 beam are determined by the following formulas:

[0098]

[0099]

[0100]

[0101] In the formula, y is the distance from O to O1, where O is the intersection of the extended line of the center point of the infrared laser galvanometer 14 and the plane containing the workpiece surface, O1 is the intersection of the left line of the processing scanning range and the plane containing the workpiece surface, z is the distance from O to O2, where O2 is the intersection of the right line of the processing scanning range and the plane containing the workpiece surface, a is the angle between the extended line of the center point of the infrared laser galvanometer 14 and the scanning range of the galvanometer, d is the distance from the center point of the infrared laser galvanometer 14 to the workpiece surface, and α is the tilt angle of the infrared laser galvanometer 14. In the continuous mode of the infrared laser 28, a = arctan(s) h / f), where s h y+z is half the side length of the processing area set at the focal plane of infrared laser 28, f is the distance from infrared laser galvanometer 14 to the focal plane, y+z is the length of the processing area at the focal plane of infrared laser 28 mapped onto the workpiece surface, v1 is the beam scanning speed of ultraviolet pulsed laser 29, v2 is the beam scanning speed of infrared continuous laser 28, and d f This is the actual side length at the focal plane of the infrared laser.

[0102] In this step, the wavelength of the infrared laser 28 is greater than the wavelength of the ultraviolet laser 29.

[0103] Infrared wavelengths range from 760nm to 1064nm, while ultraviolet wavelengths range from 190nm to 380nm.

[0104] Step 8: Adjust the positions of the vertical motion guide slider 10 and the horizontal motion guide slider 24, and process different areas of the workpiece surface according to Step 7;

[0105] Step 9: Adjust the angle of the rotary disk 22 and the position of the vertical motion guide slider 17 to level the workpiece 36, and process the inclined areas on both sides of the upper surface of the workpiece according to steps 7 and 8.

[0106] The rotation angle of the rotating disk 22 is determined by the following formula:

[0107]

[0108] In the formula, β is the rotation angle of the rotary disk 22, x1 and x2 are the positions of the two endpoints of the curved surface on the workpiece after being projected onto the reference coordinates, and y is the function curve obtained by fitting after scanning the curved surface meridian.

[0109] The vertical guide slider 17's movement distance is determined by the following formula:

[0110]

[0111] In the formula, l is the vertical movement distance of the guide rail slider 17, and x2-x1 is the distance between two points on the curved surface projected onto the reference coordinates. At that time, the rotating disk 22 rotates clockwise. At that time, the rotating disk 22 rotates counterclockwise.

[0112] Step 10: Level the rotating disk 22 and return the position of the three-axis guide rail slider to zero, and open the exhaust switch 5 to release the argon gas in the chamber;

[0113] Step 11: When the oxygen concentration sensor 33 value recovers to above 9000ppm, turn off the air inlet and outlet switches, open the door of the sealed chamber 8, remove the polished workpiece from the workpiece fixture 18 and put it into the dustproof space for storage.

[0114] In step 7, the power of the infrared fiber laser 28 is less than that of the infrared fiber laser 28 in step 8.

[0115] The original surface roughness distribution diagram of the workpiece is shown below. Figure 6 As shown, the surface roughness distribution of the workpiece after the above-mentioned multi-wavelength laser synergistic polishing is as follows: Figure 7 As shown, through Figure 7 and Figure 6 The comparison shows that the roughness distribution of the original surface was greatly improved after laser polishing, and the height in the Rz direction was reduced from 0.8μm to 0.6μm.

[0116] Figure 8 This is a logarithmic distribution of roughness frequency before and after polishing. Figure 8 It can be seen that the high-frequency roughness of the original surface is significantly removed. After multi-wavelength laser synergistic polishing, the average Ra value of the workpiece surface is reduced by 60% compared with the original surface.

[0117] The present invention provides a method for simultaneous multi-wavelength laser processing of copper-based alloy surfaces. Compared with traditional single-laser-beam polishing methods, this method significantly improves the surface quality of polished copper alloy workpieces. It avoids the large energy loss and reflection associated with using infrared lasers alone, which can lead to laser damage, reduced polishing efficiency, and increased polishing costs. Furthermore, it suppresses molten pool fluctuations and impurity precipitation during ultraviolet laser processing alone. Through the synergistic effect of ultraviolet and infrared lasers, the absorption rate of the copper alloy to infrared lasers is increased, and the surface is reconstructed under appropriate laser power, thereby improving the surface quality after polishing. Secondly, the combination of continuous laser robustness and a controllable moving four-axis substrate platform allows for the surface polishing of workpieces with a certain curvature. By adjusting the processing parameters of the relevant infrared and ultraviolet lasers, as well as the motion parameters of the substrate platform, synchronous, large-format processing can be achieved, improving the adaptability of workpiece processing materials.

[0118] With the continuous upgrading and iteration of laser technology and optical components, three-dimensional galvanometers have significantly improved the depth of laser processing, achieving very high efficiency and precision. Regarding the three-dimensional surface processing of workpieces, the existing dynamic adjustment of the focused spot's spatial position is another important means of achieving non-planar processing. The three-dimensional processing capability of a three-dimensional scanning galvanometer benefits from its dynamic focusing unit, allowing the focal point to vary within a certain range in the height direction, which is impossible for a typical two-dimensional scanning galvanometer. Upgrading and replacing the two-dimensional ultraviolet laser galvanometer 13 and infrared laser galvanometer 14 in this invention with a three-dimensional galvanometer can further improve the processing depth of the workpiece surface, thereby enabling the surface polishing of more complex curved surfaces such as engine turbine blades, worm gears, and large-curvature molds. This further increases the types of materials processed and the polishing efficiency, and allows for its application in copper-based alloy workpieces such as electrodes, brass switches, copper pipes, brass gears, brass cycloidal wheels, brass connecting rods, copper pump bodies, and valve bodies, broadening its market applications.

[0119] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for simultaneous multi-wavelength laser polishing of copper-based metal surfaces, characterized in that, A copper-based metal surface multi-wavelength laser synchronous processing device is used for synchronous polishing. The device includes a base (1), a sealed chamber (8) on the base (1), a three-axis motion guide rail inside the sealed chamber (8), a rotating disk (22) on the three-axis motion guide rail, a work panel (20) on the rotating disk (22), and a fixture (18) for clamping the workpiece to be processed on the work panel (20). An infrared processing module and an ultraviolet processing module are installed outside the sealed chamber (8). The infrared processing module includes an infrared fiber laser (28) and an infrared laser galvanometer (14). The ultraviolet processing module includes an ultraviolet laser (29) and an ultraviolet laser galvanometer (13). The synchronous polishing method includes the following steps: Step 1: Adjust the angle of the infrared laser galvanometer (14) so ​​that the processing area of ​​the infrared fiber laser (28) coincides with the processing area of ​​the ultraviolet laser (29); Step 2: Adjust the three-axis motion guide rail so that the working panel (20) is located at the focal plane of the ultraviolet laser (29); Step 3: Install the workpiece (36) in the fixture (18) and fix it; Step 4: Adjust the height of the workpiece (36) by adjusting the three-axis motion guide rail so that the surface of the workpiece (36) is located at the focal plane of the two lasers, and determine the relative position of the processing area on the workpiece surface by using the red light contour preview function in the infrared fiber laser (28). Step 5: Close the hatch of the sealed chamber (8) and fill the sealed chamber (8) with protective gas; Step 6: When the oxygen concentration drops to the specified range, turn off the inflation switch (3) and maintain an argon atmosphere in the chamber; Step 7: According to the set parameters, use an infrared fiber laser (28) pulse mode to perform laser rough polishing on the surface of the workpiece (36) to remove substances on the surface of the workpiece that may affect the surface quality after polishing. Step 8: Perform synchronous and coordinated processing on the workpiece according to the set laser scanning speed, wherein the infrared fiber laser (28) adopts continuous mode and the ultraviolet laser (29) adopts pulse mode; Step 9: Adjust the position of the workpiece (36) in the horizontal direction, and process the other areas except the workpiece surface and the galvanometer scanning area according to step 8; Step 10: By adjusting the angle of the rotary disk (22) and the position of the three-axis motion guide, process the area with curvature on the surface of the workpiece as in step 8.

2. The method for simultaneous multi-wavelength laser polishing of copper-based metal surfaces according to claim 1, characterized in that, In step 7, the power of the infrared fiber laser (28) is less than the power of the infrared fiber laser (28) in step 8.

3. The method for simultaneous multi-wavelength laser polishing of copper-based metal surfaces according to claim 1, characterized in that, The galvanometer angle of the infrared fiber laser (28) in step 1 is determined by the following formula: In the formula The rotation angle of the infrared laser galvanometer (14) is... The focal length of the infrared laser field lens (16) is... The horizontal distance between the centers of the infrared laser galvanometer (14) and the ultraviolet laser galvanometer (13) is denoted as ...

4. The method for simultaneous multi-wavelength laser polishing of copper-based metal surfaces according to claim 1, characterized in that, In step 8, the scanning speed of the infrared fiber laser (28) beam in continuous mode and the scanning speed of the ultraviolet laser (29) beam are determined by the following formulas: In the formula, y is the distance from O to O1, where O is the intersection of the extended line of the center point of the infrared laser galvanometer (14) and the plane containing the workpiece surface, O1 is the intersection of the left line of the processing scanning range and the plane containing the workpiece surface, z is the distance from O to O2, where O2 is the intersection of the right line of the processing scanning range and the plane containing the workpiece surface, and a is the angle between the extended line of the center point of the infrared laser galvanometer (14) and the scanning range of the galvanometer. The distance from the center point of the infrared laser galvanometer (14) to the workpiece surface is denoted as . The tilt angle of the infrared laser galvanometer (14) and the continuous mode of the infrared fiber laser (28) ,in The processing area is set at half the side length of the focal plane of the infrared fiber laser (28). The distance from the infrared laser galvanometer (14) to the focal plane is denoted as . The length of the processing area at the focal plane of the infrared fiber laser (28) mapped onto the workpiece surface. The beam scanning speed of the ultraviolet laser (29) is... The beam scanning speed of the infrared fiber laser (28) is... is the actual side length at the focal plane of the infrared fiber laser (28).

5. The method for simultaneous multi-wavelength laser polishing of copper-based metal surfaces according to claim 1, characterized in that, The infrared processing module and the ultraviolet processing module are respectively installed on the first column (2) and the second column (35); The infrared processing module also includes a collimator (27), an infrared laser beam expander (26), an infrared laser adapter (25), and an infrared laser field lens (16). The infrared fiber laser (28), collimator (27), infrared laser beam expander (26), infrared laser adapter (25), infrared laser galvanometer (14), and infrared laser field lens (16) are connected in sequence. A first support plate is installed on the first column (2). The infrared fiber laser (28), collimator (27) and infrared laser beam expander (26) are fixedly connected to the first support plate by a latch. The infrared laser adapter neck (25) is fixedly connected to the end of the first support plate. The infrared laser galvanometer (14) is fixedly connected to the other end of the infrared laser adapter neck (25). The ultraviolet processing module also includes an ultraviolet laser beam expander (31), an ultraviolet laser adapter (30), and an ultraviolet laser field lens (15). The ultraviolet laser (29), ultraviolet laser beam expander (31), ultraviolet laser adapter (30), ultraviolet laser galvanometer (13), and ultraviolet laser field lens (15) are connected in sequence. A second support plate is installed on the second column (35), and the ultraviolet laser (29) is fixed on the second support plate. The ultraviolet laser beam expander (31) and the ultraviolet laser (29) are connected in sequence. The ultraviolet laser adapter neck (30) is fixedly connected to the ultraviolet laser (29) at one end and to the ultraviolet laser galvanometer (13) at the other end. The ultraviolet laser adapter neck (30) and the infrared laser adapter neck (25) are partially installed in the sealed chamber (8). The ultraviolet laser adapter neck (30) and the infrared laser adapter neck (25) are sealed to the chamber wall of the sealed chamber (8) with sealant. The infrared laser optical path and the ultraviolet laser optical path are installed into the chamber through the slots provided on the wall of the sealed chamber (8) and sealed.

6. The method for simultaneous multi-wavelength laser polishing of copper-based metal surfaces according to claim 1, characterized in that, The three-axis motion guide rail includes a vertical motion guide rail (11), and a horizontal motion guide rail (12) is mounted on the vertical motion guide rail (11) via a vertical motion guide rail slider (10); a vertical motion guide rail (23) is slidably mounted on the horizontal motion guide rail (12), and a rotary disk (22) is slidably mounted on the vertical motion guide rail (23).

7. The method for simultaneous multi-wavelength laser polishing of copper-based metal surfaces according to claim 5, characterized in that, The ultraviolet laser beam expander (31) is installed inside the ultraviolet laser adapter neck (30); the ultraviolet laser galvanometer (13) and the ultraviolet laser field lens (15) are connected by an adapter ring thread.

8. The method for simultaneous multi-wavelength laser polishing of copper-based metal surfaces according to claim 1, characterized in that, The sealed chamber (8) is equipped with a chamber pressure detection sensor (6) on its side wall and an oxygen concentration sensor (33) on its top.

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