Composite welding device based on collaborative operation of three laser beams and welding method thereof

Abstract

The invention discloses a hybrid welding device based on three-beam laser collaborative operation and a welding method of the hybrid welding device, and belongs to the technical field of laser hybrid welding. The device comprises a computer, a multi-laser master control system, a high-power continuous MOPA optical fiber laser, a Q-switched pulse optical fiber laser, an Nd: YAG laser, a laser welding system, a laser forging system, a laser polishing system, a mechanical arm and a temperature sensor. According to the method, three laser processes of laser welding, laser forging and laser polishing are integrated in a continuous process, and a computer is matched with all systems, so that the apparent quality of a welding seam is improved, the roughness is reduced, the residual stress is regulated and controlled, and microdefects are reduced in one process at the same time; and the processing efficiency and the comprehensive performance of the joint are obviously improved. According to the method, the plastic deformation resistance of weld metal can be reduced, the effect of eliminating defects and implanting pressure stress through laser forging can be improved, and the polishing efficiency and precision can be improved.

Description

Technical Field

[0001] This invention relates to the field of laser composite welding technology, specifically to a composite welding device and welding method based on the coordinated operation of three laser beams. Background Technology

[0002] Laser welding technology is widely used in automotive, aerospace, and electronics manufacturing due to its advantages such as high energy density, rapid processing, and narrow heat-affected zone. However, traditional laser welding suffers from problems such as high residual stress and numerous microscopic defects in the weld, affecting the mechanical properties and service life of the joint. To address these issues, post-processing techniques such as mechanical polishing or heat treatment are typically employed, but these methods are complex, inefficient, and prone to introducing new damage. Introducing laser forging during the welding process can eliminate microscopic defects such as surface porosity in the weld and implant residual compressive stress, which is beneficial for improving joint performance. However, because in-line laser forging cannot form a laser absorption layer, it can lead to surface ablation of the weld, increasing surface roughness and negatively impacting fatigue performance. Summary of the Invention

[0003] The purpose of this invention is to provide a composite welding device and method based on the coordinated operation of three laser beams. Through the synergistic effect of the three laser beams, residual stress in the welded joint is controlled, the problem of numerous defects is solved, and the surface condition is improved, thereby enhancing the overall performance of the joint.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A composite welding device based on three-beam laser collaborative operation includes a computer, a multi-laser control system, a high-power continuous MOPA fiber laser, a Q-switched pulsed fiber laser, an Nd:YAG laser, a laser welding system, a laser forging system, and a laser polishing system. The computer is electrically connected to the multi-laser control system. The multi-laser control system is used to control the high-power continuous MOPA fiber laser, the Q-switched pulsed fiber laser, and the Nd:YAG laser, and to control the working path and start / stop status of the laser welding system, the laser forging system, and the laser polishing system. The high-power continuous MOPA fiber laser is used to provide continuous laser light to the laser welding system. The Q-switched pulsed fiber laser is used to provide pulsed laser light to the laser forging system. The Nd:YAG laser is used to provide the laser polishing system with short-pulse, high-peak-power laser. The laser welding system is used to connect two metal plates to form a weld using a continuous laser from a welding laser head. The laser forging system is used to perform laser forging on the weld formed by the laser welding system using the pulsed laser of the forging laser head, thereby strengthening the performance of the welded joint. The laser polishing system is used to laser polish the weld seam after laser forging by the laser forging system using the pulsed laser of the polishing laser head, thereby improving the surface quality.

[0005] Furthermore, a composite welding device based on the coordinated operation of three laser beams also includes a robotic arm, which is used to control the distance between the forging laser head and the welding laser head so that the laser forging is within a suitable temperature range. Furthermore, a composite welding device based on the coordinated operation of three laser beams also includes a temperature sensor. The temperature sensor is used to record the real-time temperature of the weld formed by the laser welding system and transmit the real-time temperature of the weld to the computer. The computer is used to analyze and compare the real-time temperature data collected by the temperature sensor with the originally stored laser forging temperature range. When the real-time temperature data is within the originally stored laser forging temperature range, the computer controls the robotic arm to move the forging laser head to the corresponding position on the weld and transmits the laser forging command to the multi-laser control system.

[0006] Furthermore, the high-power continuous MOPA fiber laser includes an optical seed source, a gain fiber, a resonant cavity, a multi-stage fiber amplifier, a stripper, and an additional pump source connected in sequence. The optical seed source is a semiconductor laser tube, the pump source provides energy to the gain fiber and the multi-stage fiber amplifier, and the stripper is used to remove residual pump light.

[0007] Furthermore, the Q-switched pulsed fiber laser includes a Q-switched oscillator, a gain fiber, and a solid-state amplifier connected in sequence.

[0008] Furthermore, the Nd:YAG laser includes a pump source, a focusing cavity, a gain medium, a resonant cavity, and an additional cooling system connected in sequence. The pump source is a xenon lamp, and the cooling system is used to prevent the gain medium, pump lamp, and focusing cavity from overheating.

[0009] Furthermore, the laser welding system includes a welding laser head and a connection between the welding laser head and a high-power continuous MOPA fiber laser.

[0010] Furthermore, the laser forging system includes a forging laser head and a robotic arm, with the robotic arm connected to the forging laser head and the forging laser head connected to a Q-switched pulsed fiber laser.

[0011] Furthermore, the laser polishing system includes a polishing laser head, which is connected to an Nd:YAG laser.

[0012] A composite welding method based on the coordinated operation of three laser beams includes the following steps: S1. Using an artificial intelligence model with laser forging parameters, weld temperature, and material properties as input, predict the surface roughness and strengthening depth of the laser forging zone. Compare the predicted results with the results obtained from the laser forging experiment. If they are consistent, store the predicted data in the computer; otherwise, re-predict.

[0013] S2. The computer plans the running path for metal connection, analyzes and determines the temperature range of laser forging, and generates and saves the original data records.

[0014] S3, the multi-laser master control system controls the high-power continuous MOPA fiber laser, Q-switched pulsed fiber laser and Nd:YAG laser to deliver the laser to the welding laser head of the laser welding system, the forging laser head of the laser forging system and the polishing laser head of the laser polishing system, respectively.

[0015] S4. The multi-laser control system starts the welding laser head in the laser welding system to begin welding work along the preset running path, forming a weld. The temperature sensor detects the temperature of the weld surface in real time, providing a basis for the laser forging position.

[0016] S5. When the temperature of the weld seam drops to the original stored laser forging temperature range, the multi-laser control system starts the forging laser head of the laser forging system to begin laser forging along the weld seam trajectory. Since the temperature of subsequent weld seams will be superimposed during the welding process, the position of the laser forging head needs to be changed in real time to keep the laser forging temperature within the temperature range. At this time, the computer will send a movement command to the robotic arm to change the position of the laser forging head in real time based on the temperature data detected in real time by the temperature sensor, until the entire weld seam is forged.

[0017] S6, the multi-laser control system shuts down the laser welding system and the laser forging system, causing the welding laser head and the forging laser head to stop working.

[0018] S7. Based on the laser forging depth and surface roughness data predicted by the artificial intelligence model stored in the computer, the computer generates information data on the laser polishing depth through analysis and comparison, and inputs it into the multi-laser control system to avoid eliminating the strengthening effect of laser forging on the weld.

[0019] S8. The multi-laser control system starts the laser polishing system and controls the running path of the polishing laser head in the laser polishing system according to the information data of the laser polishing depth, so that the polishing laser head performs laser polishing on the weld according to the polishing depth until the entire weld surface is polished.

[0020] The beneficial effects of this invention are as follows: 1. This invention uses an artificial intelligence model to predict the depth of laser forging and surface roughness of the weld, obtains forging depth and surface roughness data, visualizes these data, provides a basis for laser polishing depth, and avoids eliminating the strengthening effect of laser forging on the weld.

[0021] 2. This invention uses a robotic arm to control the distance between the laser forging head and the laser welding head, changing the position of the laser forging and keeping the laser forging within the temperature range stored in the computer.

[0022] 3. The method of this invention integrates three laser processes—laser welding, laser forging, and laser polishing—into a continuous process. Through the cooperation of a computer and various systems, it simultaneously improves the surface quality of the weld, reduces roughness, controls residual stress, and reduces microscopic defects within a single step, significantly improving processing efficiency and overall joint performance. Furthermore, the online integration of the three laser beams generates a significant coupling effect, maximizing the effectiveness of each beam. Specifically, the temperature field of laser welding reduces the resistance to plastic deformation of the weld metal, which is beneficial for improving the defect elimination and compressive stress implantation effects of laser forging. On the other hand, the welding temperature also provides a temperature basis for laser polishing, improving polishing efficiency and precision. Attached Figure Description

[0023] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort: Figure 1 This is a schematic block diagram of the composite welding device of the present invention; Figure 2 This is a flowchart of the artificial intelligence model prediction process for the composite welding method of the present invention.

[0024] In the diagram: 1. Computer; 2. Multi-laser control system; 3. High-power continuous MOPA fiber laser; 4. Q-switched pulsed fiber laser; 5. Nd:YAG laser; 6. Laser welding system; 7. Laser forging system; 8. Laser polishing system; 9. Laser welding head; 10. Laser forging head; 11. Laser polishing head; 12. Robotic arm. Detailed Implementation

[0025] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0026] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper surface," "lower surface," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "forward," "reverse," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0027] like Figure 1 As shown, the composite welding device based on the coordinated operation of three laser beams includes a computer 1, a multi-laser control system 2, a high-power continuous MOPA fiber laser 3, a Q-switched pulse fiber laser 4, an Nd:YAG laser 5, a laser welding system 6, a laser forging system 7, a laser polishing system 8, a robotic arm 12, and a temperature sensor. The multi-laser control system 2 is used to control the working path and start / stop status of the high-power continuous MOPA fiber laser 3, Q-switched pulsed fiber laser 4 and Nd:YAG laser 5 and the corresponding laser systems in the welding device. A high-power continuous MOPA fiber laser 3 is used to provide continuous laser light to the laser welding system 6. The high-power continuous MOPA fiber laser 3 includes an optical seed source, a gain fiber, a resonant cavity, a multi-stage fiber amplifier, a stripper, and an additional pump source connected in sequence. The optical seed source is a semiconductor laser tube. The pump source provides energy to the gain fiber and the multi-stage fiber amplifier. The stripper is used to remove residual pump light and protect related devices. A Q-switched pulsed fiber laser 4 is used to provide pulsed laser light to the laser forging system 7. The Q-switched pulsed fiber laser 4 includes a Q-switched oscillator, a gain fiber, and a solid-state amplifier connected in sequence. The Nd:YAG laser 5 is used to provide short-pulse, high-peak-power laser to the laser polishing system 8. The Nd:YAG laser 5 includes a pump source, a focusing cavity, a gain medium, a resonant cavity, and an additional cooling system connected in sequence. The pump source is a xenon lamp, and the cooling system is used to prevent the gain medium, pump lamp, and focusing cavity from overheating. A laser welding system 6 is used to connect two metal plates to form a weld using a continuous laser from a welding laser head 9; the laser welding system 6 includes a welding laser head 9 and a high-power continuous MOPA fiber laser 3 connected together. The laser forging system 7 is used to laser forge the weld formed by the laser welding system to enhance the performance of the weld joint; the laser forging system 7 includes a forging laser head 10 and a robotic arm 12, the robotic arm 12 is connected to the forging laser head 10, and the forging laser head 10 is connected to the Q-switched pulsed fiber laser 4. The laser polishing system 8 is used to laser polish the weld seam after laser forging in the laser forging system to improve the surface quality; the laser polishing system 8 includes a polishing laser head 11, which is connected to the Nd:YAG laser 5. The robotic arm 12 is used to control the distance between the forging laser head 10 and the welding laser head 9, so that the laser forging is within a suitable temperature range; A temperature sensor is used to record the real-time temperature of the weld formed by the laser welding system and transmit the real-time temperature of the weld to a computer. The computer is used to analyze and compare the real-time temperature data collected by the temperature sensor with the originally stored laser forging temperature range. When the real-time temperature data is within the originally stored laser forging temperature range, the computer controls the robotic arm to move the forging laser head to the corresponding position on the weld and transmits the laser forging command to the multi-laser control system.

[0028] This invention employs an artificial intelligence model to predict the laser forging depth and surface roughness of the weld, obtaining forging depth and surface roughness data. This data is then visualized to provide a basis for laser polishing depth, thus avoiding the elimination of the strengthening effect of laser forging on the weld. This invention uses a robotic arm to control the distance between the laser forging head and the laser welding head, changing the position of the laser forging and ensuring that the laser forging occurs within the temperature range stored in the computer.

[0029] like Figure 2 As shown, a composite welding method based on the coordinated operation of three laser beams includes the following steps: S1. Using an artificial intelligence model with laser forging parameters, weld temperature, and material properties as input, predict the surface roughness and strengthening depth of the laser forging zone. Compare the predicted results with the results obtained from the laser forging experiment. If they are consistent, store the predicted data in the computer; otherwise, re-predict.

[0030] S2. The computer plans the running path for metal connection, analyzes and determines the temperature range of laser forging, and generates and saves the original data records.

[0031] S3, the multi-laser master control system controls the high-power continuous MOPA fiber laser, Q-switched pulsed fiber laser and Nd:YAG laser to deliver the laser to the welding laser head of the laser welding system, the forging laser head of the laser forging system and the polishing laser head of the laser polishing system, respectively.

[0032] S4. The multi-laser control system starts the welding laser head in the laser welding system to begin welding work along the preset running path, forming a weld. The temperature sensor detects the temperature of the weld surface in real time, providing a basis for the laser forging position.

[0033] S5. When the temperature of the weld seam drops to the original stored laser forging temperature range, the multi-laser control system starts the forging laser head of the laser forging system to begin laser forging along the weld seam trajectory. Since the temperature of subsequent weld seams will be superimposed during the welding process, the position of the laser forging head needs to be changed in real time to keep the laser forging temperature within the temperature range. At this time, the computer will send a movement command to the robotic arm to change the position of the laser forging head in real time based on the temperature data detected in real time by the temperature sensor, until the entire weld seam is forged.

[0034] S6, the multi-laser control system shuts down the laser welding system and the laser forging system, causing the welding laser head and the forging laser head to stop working.

[0035] S7. Based on the laser forging depth and surface roughness data predicted by the artificial intelligence model stored in the computer, the computer generates information data on the laser polishing depth through analysis and comparison, and inputs it into the multi-laser control system to avoid eliminating the strengthening effect of laser forging on the weld.

[0036] S8. The multi-laser control system starts the laser polishing system and controls the running path of the polishing laser head in the laser polishing system according to the information data of the laser polishing depth, so that the polishing laser head performs laser polishing on the weld according to the polishing depth until the entire weld surface is polished.

[0037] This invention integrates three laser processes—laser welding, laser forging, and laser polishing—into a continuous process. Through the coordinated operation of a computer and various systems, it simultaneously improves the surface quality of the weld, reduces roughness, controls residual stress, and minimizes micro-defects within a single step, significantly enhancing processing efficiency and overall joint performance. Furthermore, the online integration of the three laser beams generates a significant coupling effect, maximizing the effectiveness of each beam. The temperature field of laser welding reduces the resistance to plastic deformation of the weld metal, improving the defect elimination and compressive stress implantation effects of laser forging. Simultaneously, the welding temperature provides a temperature basis for laser polishing, enhancing polishing efficiency and precision.

[0038] Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described herein, as well as the features of those embodiments or examples, without contradiction. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A composite welding device based on the coordinated operation of three laser beams, characterized in that: It includes a computer, a multi-laser control system, a high-power continuous MOPA fiber laser, a Q-switched pulsed fiber laser, an Nd:YAG laser, a laser welding system, a laser forging system, and a laser polishing system, wherein the computer is electrically connected to the multi-laser control system; The multi-laser control system is used to control the high-power continuous MOPA fiber laser, the Q-switched pulsed fiber laser, and the Nd:YAG laser, and to control the working path and start / stop status of the laser welding system, the laser forging system, and the laser polishing system. The high-power continuous MOPA fiber laser is used to provide continuous laser light to the laser welding system. The Q-switched pulsed fiber laser is used to provide pulsed laser light to the laser forging system. The Nd:YAG laser is used to provide the laser polishing system with short-pulse, high-peak-power laser. The laser welding system is used to connect two metal plates to form a weld using a continuous laser from a welding laser head. The laser forging system is used to perform laser forging on the weld formed by the laser welding system using the pulsed laser of the forging laser head, thereby strengthening the performance of the welded joint. The laser polishing system is used to laser polish the weld seam after laser forging by the laser forging system using the pulsed laser of the polishing laser head, thereby improving the surface quality.

2. The composite welding device based on three-beam laser collaborative operation according to claim 1, characterized in that: It also includes a robotic arm, which is used to control the distance between the forging laser head and the welding laser head so that the laser forging is within a suitable temperature range.

3. The composite welding device based on three-beam laser collaborative operation according to claim 2, characterized in that: It also includes a temperature sensor, which records the real-time temperature of the weld formed by the laser welding system and transmits the real-time temperature of the weld to a computer. The computer analyzes and compares the real-time temperature data collected by the temperature sensor with the originally stored laser forging temperature range. When the real-time temperature data is within the originally stored laser forging temperature range, the computer controls the robotic arm to move the forging laser head to the corresponding position on the weld and transmits the laser forging command to the multi-laser control system.

4. The composite welding device based on three-beam laser collaborative operation according to claim 3, characterized in that: The high-power continuous MOPA fiber laser includes an optical seed source, a gain fiber, a resonant cavity, a multi-stage fiber amplifier, a stripper, and an additional pump source connected in sequence. The optical seed source is a semiconductor laser tube. The pump source provides energy to the gain fiber and the multi-stage fiber amplifier. The stripper is used to remove residual pump light.

5. The composite welding device based on three-beam laser collaborative operation according to claim 4, characterized in that: The Q-switched pulsed fiber laser includes a Q-switched oscillator, a gain fiber, and a solid-state amplifier connected in sequence.

6. The composite welding device based on three-beam laser collaborative operation according to claim 5, characterized in that: The Nd:YAG laser includes a pump source, a focusing cavity, a gain medium, a resonant cavity, and an additional cooling system connected in sequence. The pump source is a xenon lamp, and the cooling system is used to prevent the gain medium, pump lamp, and focusing cavity from overheating.

7. The composite welding device based on three-beam laser collaborative operation according to claim 6, characterized in that: The laser welding system includes a welding laser head and a high-power continuous MOPA fiber laser connected together.

8. The composite welding device based on three-beam laser collaborative operation according to claim 7, characterized in that: The laser forging system includes a forging laser head and a robotic arm. The robotic arm is connected to the forging laser head, and the forging laser head is connected to a Q-switched pulsed fiber laser.

9. The composite welding device based on three-beam laser collaborative operation according to claim 8, characterized in that: The laser polishing system includes a polishing laser head, which is connected to an Nd:YAG laser.

10. The composite welding method based on the composite welding device of three laser beams working in concert according to claim 9, characterized in that, Includes the following steps: S1. Using an artificial intelligence model with laser forging parameters, weld temperature and material properties as input, predict the surface roughness and strengthening depth of the laser forging zone. Compare the predicted results with the results obtained from the laser forging experiment. If they are consistent, store the predicted data in the computer; otherwise, re-predict. S2. The computer plans the running path for metal connection, analyzes and determines the temperature range of laser forging, and generates and saves the original data records. S3. The multi-laser master control system controls the high-power continuous MOPA fiber laser, Q-switched pulsed fiber laser and Nd:YAG laser to deliver the laser to the welding laser head of the laser welding system, the forging laser head of the laser forging system and the polishing laser head of the laser polishing system, respectively. S4. The multi-laser control system starts the welding laser head in the laser welding system to begin welding work along the preset running path, forming a weld. The temperature sensor detects the temperature of the weld surface in real time, providing a basis for the laser forging position. S5. When the temperature of the weld seam drops to the original stored laser forging temperature range, the multi-laser control system starts the forging laser head of the laser forging system to begin laser forging along the weld seam trajectory. Since the temperature of subsequent weld seams will be superimposed during the welding process, the position of the laser forging head needs to be changed in real time to keep the laser forging temperature within the temperature range. At this time, the computer will send a movement command to the robotic arm to change the position of the laser forging head in real time based on the temperature data detected in real time by the temperature sensor until the entire weld seam is forged. S6. The multi-laser control system shuts down the laser welding system and the laser forging system, causing the welding laser head and the forging laser head to stop working. S7. Based on the laser forging depth and surface roughness data predicted by the artificial intelligence model stored in the computer, the computer generates information data on the laser polishing depth through analysis and comparison, and inputs it into the multi-laser control system to avoid eliminating the strengthening effect of laser forging on the weld. S8. The multi-laser control system starts the laser polishing system and controls the running path of the polishing laser head in the laser polishing system according to the information data of the laser polishing depth, so that the polishing laser head performs laser polishing on the weld according to the polishing depth until the entire weld surface is polished.

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