Liquid filling and laser shock composite forming system and method

Abstract

This invention discloses a liquid filling and laser shock composite forming system and method, comprising: a laser emitting device, a liquid filling device, and a workpiece platform; the workpiece platform includes a base, a worktable mounted on the base, and adjustable clamps on the side of the worktable for clamping the workpiece to be formed; sealing devices are respectively provided at both ends of the worktable for sealing both ends of the workpiece to be formed; the sealing devices are connected to the liquid filling device via pipes, and the liquid filling device is used to fill the cavity of the workpiece to be formed with liquid at a set pressure, which is connected to the sealing devices; the laser emitting device is used to emit a laser beam towards the workpiece to be formed, and a laser rangefinder is used to detect the distance between the laser impact point and a preset reference surface in real time, comparing the distance with the set distance, and adjusting the position of the worktable according to the distance deviation. This invention can quickly and accurately obtain the optimal liquid pressure, solving the problem of inaccurate determination of liquid pressure in the prior art.

Description

Technical Field

[0001] This invention relates to the field of laser forming technology, and in particular to a liquid filling and laser shock composite forming system and method. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Large-size, complex, multi-cavity aluminum profiles are widely used in high-speed trains, aerospace, and other fields. Existing technologies for forming aluminum alloy profiles mostly employ the following methods:

[0004] (1) Compression molding: Relying on rigid molds, the profile is subjected to external force by a press to fit the mold cavity. However, for large-sized, complex, multi-cavity aluminum profiles, large molds need to be customized, which is costly and time-consuming. Furthermore, large-sized profiles are prone to wrinkles and cracks due to uneven pressure distribution in the mold. The springback and deformation of the mold forming process require a lot of manual grinding and correction, and the precision is difficult to control.

[0005] (2) Laser shock forming: This method relies on simple tooling fixtures to fix the workpiece and uses laser-induced shock waves to cause local plastic deformation of the profile. However, relying solely on the laser shock wave, the cavity support of complex multi-cavity profiles is insufficient, and collapse is likely to occur; the laser parameters (energy, pulse width) are difficult to control to meet the needs of large-size profiles with long distances and multiple curvatures, resulting in poor forming consistency; the laser acts directly on the profile surface, which can easily lead to ablation or microcracks due to energy concentration.

[0006] (3) Fluid filling and forming: Fluid is filled into the profile and pressure is applied, and expansion is achieved with a simple mold; This method relies on manual or open-loop pressure control. The fluid filling pressure and forming curvature are not precisely related, and it relies on trial and error based on experience; It is difficult to solve the problem of synchronous pressure control of multiple cavities in large-size multi-cavity profiles, and cross-sectional deformation is easily caused by uneven pressure in each cavity; In addition, there is a lack of intelligent feedback, and open-loop control cannot correct pressure and position deviations in real time, resulting in a low first-piece pass rate. Summary of the Invention

[0007] To address the aforementioned problems, this invention proposes a liquid-filling and laser-shock composite forming system and method. This system utilizes a liquid-filling and laser-shock composite forming method, employing a high-energy short-pulse laser to impact the surface of an aluminum alloy profile. Simultaneously, a liquid at a certain pressure is filled into the cavity of the aluminum alloy profile. The liquid in the cavity acts as a force transmitter, ensuring that when one side is laser-shocked, the opposite side is also subjected to the force transmitted by the liquid. This allows large-sized, complex, multi-cavity aluminum alloy profiles to achieve ideal forming accuracy.

[0008] According to a first aspect of the present invention, a liquid filling and laser shock composite forming system is provided, characterized in that it comprises: a laser emitting device, a liquid filling device, and a workpiece platform; the workpiece platform includes a base, a worktable is provided on the base, and an adjustable clamp is provided on the side of the worktable for clamping the workpiece to be formed; sealing devices are respectively provided at both ends of the worktable for sealing both ends of the workpiece to be formed; the sealing devices are connected to the liquid filling device through pipes, and the liquid filling device is used to fill the cavity of the workpiece to be formed with liquid at a set pressure connected to the sealing device; the laser emitting device is used to emit a laser to the workpiece to be formed, and a laser rangefinder is used to detect the distance between the laser shock point and a preset reference surface in real time, compare the distance with the set distance, and adjust the position of the worktable according to the distance deviation.

[0009] As a further embodiment, a rack is arranged along a preset direction, and a base is positioned above the rack and connected to it via gears; rotation of the gears can drive the base to move on the rack; a first lead screw transmission mechanism is arranged vertically on the base, and the first lead screw transmission mechanism is connected to the worktable, which can move vertically under the drive of the first lead screw transmission mechanism; a second lead screw transmission mechanism is arranged perpendicular to the rack, and the second lead screw transmission mechanism is connected to the rack, which, together with the base and the worktable on it, can move under the drive of the second lead screw transmission mechanism.

[0010] As a further embodiment, the adjustable fixture includes a pressure plate and a telescopic structure. One end of the telescopic structure is fixed to the workbench, and the other end is fixed to the pressure plate. The pressure plate is arranged along the length of the workbench and is provided with multiple fastening bolts.

[0011] As a further embodiment, the shape of the sealing device is adapted to the cross-sectional shape of the workpiece to be formed, and the sealing device is provided with a double-lip seal to achieve a seal between the sealing device and the workpiece to be formed.

[0012] As a further embodiment, the sealing device is equipped with a pressure sensor to detect the liquid pressure in the cavity of the workpiece to be formed; the liquid filling device includes a hydraulic pump and a pressure regulating valve, which controls the liquid pressure in the cavity of the workpiece to be formed to remain stable.

[0013] As a further solution, it also includes: an automatic black tape pasting device, which includes: a robot arm connecting platform, a tape mounting mechanism, a tape guiding component, and a pressure roller; the top of the robot arm connecting platform is connected to the robot arm, and the tape guiding component and the pressure roller are respectively connected to the opposite sides of the bottom; the tape mounting mechanism is set above the pressure roller; the black tape is set on the tape mounting mechanism, and under the guidance of the tape guiding component, the robot arm drives the tape guiding component and the pressure roller to move forward along a preset trajectory through the robot arm connecting platform; first, the end of the black tape passes under the pressure roller and is pasted onto the workpiece to be formed, and during the movement, the black tape is continuously released and pressed and pasted onto the surface of the workpiece by the pressure roller.

[0014] As a further option, it also includes: a main control system, which is used to realize closed-loop operation control of the laser emitting device and the liquid filling device, as well as movement control of the working platform.

[0015] According to a second aspect of the present invention, a liquid filling and laser shock lithography composite forming method is provided, comprising:

[0016] Curvature analysis was performed on the three-dimensional model of the target aluminum alloy profile to obtain the theoretical radius of curvature;

[0017] A three-dimensional model of an aluminum alloy profile with a proportional scale was established. The correspondence between liquid pressure and theoretical radius of curvature was obtained through data fitting, and the optimal liquid pressure and laser energy data were determined.

[0018] Determine the initial dimensions of the target aluminum alloy profile and complete the cutting process;

[0019] Seal and fix both ends of the target aluminum alloy profile, and automatically stick black tape on the surface of the target aluminum alloy profile to form an absorption layer;

[0020] A liquid with optimal pressure is injected into the target aluminum alloy profile, and laser energy is applied to the upper surface of the target aluminum alloy profile to perform laser impact forming. During the impact process, the liquid pressure inside the target aluminum alloy profile and the distance between the laser impact point and the preset reference surface are kept stable.

[0021] As a further approach, the relationship between liquid pressure and radius of curvature is obtained through data fitting, specifically:

[0022] ;

[0023] Where R is the radius of curvature. For liquid pressure, Where L is the arc height value, and L is the length of the aluminum alloy profile plate; , Laser energy, The pulse width. The radius of the light spot is... This is the ratio of plasma thermal energy to internal energy, and is a set value.

[0024] As a further solution, the following steps are also taken: After the impact is completed, the target aluminum alloy profile is scanned using a 3D scanner to compare the actual radius of curvature with the theoretical radius of curvature. If the error exceeds the allowable range, it is corrected. If the error is within the allowable range, the liquid in the target aluminum alloy profile is extracted and recovered, the profile part connected to the sealing device is cut off, and then the cut profile is cleaned and polished to complete the processing.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] (1) The present invention adopts a composite forming method of laser shock and liquid filling. The liquid provides flexible support for the complex multi-cavity interior. The liquid plays the role of transmitting force in the cavity, so that when one side of the profile is laser-shocked, the opposite side can also be subjected to the force transmitted by the liquid. This can avoid local stress concentration, reduce the cracking rate and cross-sectional distortion rate of complex profiles, and solve the problem that the multi-cavity profiles in the prior art are not effectively supported, which leads to easy collapse and cross-sectional distortion due to laser shock.

[0027] (2) This invention fills the multi-cavity profile with liquid using a liquid filling device and precisely controls and maintains the pressure, while ensuring synchronous pressure control of multiple cavities through a sealing device, thus solving the problem of uneven pressure in conventional liquid-filled multi-cavity profiles. A laser rangefinder is used to correct the laser focal length in real time; a 3D scanner provides feedback on processing errors, thereby readjusting process parameters to achieve closed-loop control of the entire impact process and ensure processing accuracy.

[0028] (3) The present invention designs an automatic black tape pasting device, which is linked with a robotic arm for control, and can achieve automatic and precise pasting of black tape without bubbles or wrinkles; and seamlessly connects with the laser impact process, reducing the time consumption of this process and improving work efficiency.

[0029] (4) The present invention aims to minimize the error between the calculated value and the simulated value. Through simulation and data fitting, a corresponding mapping relationship between liquid pressure and theoretical radius of curvature is established. The optimal liquid pressure can be directly determined by inputting the corresponding parameter values. The liquid pressure can be adjusted in real time according to parameter changes. Compared with the existing technology of adjusting the pressure based on experience or multiple experiments, the method of the present invention can quickly and accurately obtain the optimal liquid pressure, improve pressure accuracy, improve efficiency, solve the problem of difficult accurate determination of liquid pressure in the existing technology, and provide key technical support for the forming of large-size complex aluminum profiles.

[0030] Other features and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the liquid filling and laser shock composite forming system in an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the device cluster control logic in an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the workpiece platform structure in an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the adjustable clamp structure in an embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the extendable structure of the adjustable clamp in an embodiment of the present invention;

[0036] Figure 6 This is a schematic diagram of the sealing device structure in an embodiment of the present invention;

[0037] Figure 7 This is a schematic diagram illustrating the mating relationship between the base and the rack in an embodiment of the present invention;

[0038] Figure 8 This is a schematic diagram of the workpiece to be formed in an embodiment of the present invention;

[0039] Figure 9 This is a schematic diagram showing the positional relationship between the impact point and the reference plane in an embodiment of the present invention;

[0040] Figure 10 This is a schematic diagram of the automatic black tape application device in an embodiment of the present invention;

[0041] Figure 11 This is a flowchart of the liquid filling and laser shock composite forming method in an embodiment of the present invention;

[0042] The components include: 1. rack and pinion seat; 2. base; 3. sealing device; 4. worktable; 5. workpiece to be formed; 6. first lead screw transmission mechanism; 7. lead screw nut; 8. second lead screw transmission mechanism; 9. fastening bolt; 10. adjustable clamp; 11. 3D scanner; 12. condenser lens; 13. reflector; 14. laser; 15. water spray robot; 16. robotic arm; 17. automatic black tape application device; 18. hydraulic system; 19. 20. Oil-water medium pressure sensor; 21. Pipeline; 22. Main control system; 23. Pressure plate; 24. Telescopic structure; 25. Flat plate; 26. V-shaped support; 27. Aluminum alloy frame; 28. Mounting groove; 29. ​​Sealing ring; 30. Laser impact point A; 31. Laser output port; 32. Reference surface P; 33. Laser rangefinder; 34. Robotic arm connection platform; 35. Black tape installation mechanism; 36. Tape guide assembly; 37. Pressure roller. Detailed Implementation

[0043] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0044] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0045] Example 1

[0046] In one or more embodiments, a liquid filling and laser shock blasting composite forming system is disclosed, combining... Figure 1 Specifically, it includes: a laser emitting device, a liquid filling device, and a workpiece platform; among which, combined with Figure 3 The workpiece platform includes a base 2, on which a worktable 4 is mounted. An adjustable clamp 10 is mounted on the side of the worktable 4 for clamping the workpiece 5 to be formed. Sealing devices 3 are mounted at both ends of the worktable for sealing both ends of the workpiece to be formed. The sealing devices 3 are connected to a liquid filling device via a pipe 20. The liquid filling device is used to fill the cavity of the workpiece to be formed with liquid at a set pressure, which is connected to the sealing device. A laser emitting device is used to emit a laser to the workpiece to be formed. A laser rangefinder is used to detect the distance between the laser impact point and the preset reference surface in real time. The distance is compared with the set distance, and the position of the worktable is adjusted according to the distance deviation.

[0047] In this embodiment, the worktable 4 can move in the X, Y, and Z directions. Specifically, a rack seat 1 with a rack is provided along the X direction, and the base 2 is located above the rack and connected to the rack via gears; combined with Figure 7 The base has a groove at the bottom, and at least one pair of gears driven by a motor are installed in the groove. The two gears are connected to the output shaft of the motor respectively. The rack is adapted to and meshes with the gears. The rotation of the gears can drive the base to move back and forth on the rack (X direction) to realize long-distance transmission of the worktable.

[0048] When aligning long-distance workpieces or performing continuous impact processing on multiple areas, the movement of the workpiece to be formed in the X direction will be adjusted. For example, when a large, complex, multi-cavity aluminum profile to be formed is placed on the worktable, the position of the worktable needs to be adjusted along the length of the profile (X direction) so that the starting end of the profile is aligned with the laser impact area. Alternatively, when the laser impact needs to cover multiple different areas of the profile, the gear and rack drive will gradually move the worktable along the X direction according to a preset path so that the unprocessed areas enter the laser's effective range in sequence.

[0049] A first lead screw transmission mechanism is set on the base along the vertical direction (Z direction). The first lead screw transmission mechanism 6 includes a lead screw vertically set on the edge of the base and a guide rod set parallel to the lead screw. The worktable is sleeved on the lead screw and the guide rod and is connected to the lead screw through a slider or lead screw nut 7. The slider is adapted to the lead screw, and the lead screw is connected to the drive motor. The drive motor drives the lead screw to rotate, and the lead screw can drive the worktable to move up and down along the Z direction.

[0050] When performing focal length stabilization control, the position of the workpiece to be formed in the Z direction will be adjusted; for example, during laser impact, the laser rangefinder detects the distance between the laser impact point and the preset reference surface in real time. If the distance deviates from the set focal length due to local deformation of the profile, the first lead screw drive immediately drives the worktable to rise and fall in the vertical direction (Z direction) to restore the distance to the set focal length, ensuring that the size of the laser spot remains unchanged during the impact process.

[0051] A second lead screw transmission mechanism is set along the direction perpendicular to the rack (Y direction). The second lead screw transmission mechanism 8 also includes a lead screw and a guide rod arranged parallel to each other. The lead screw and the guide rod are fixed on the ground in the horizontal direction. The lead screw and the guide rod pass through the rack seat 1. The rack seat 1 is connected to the lead screw through a slider. The slider is adapted to the lead screw. By driving the rack to rotate, the rack, together with the base and the worktable on it, can be driven to move back and forth in the Y direction.

[0052] When adapting the workpiece's lateral processing range and performing multi-area continuous impact processing, the movement of the workpiece to be formed in the Y direction will be adjusted. For example, when changing multi-cavity profiles with different cross-sectional widths, the second lead screw transmission mechanism drives the rack, base, and worktable to move laterally (in the Y direction) perpendicular to the length of the profile, ensuring that the laser can accurately cover the processing area in the width direction of the profile. Alternatively, when cooperating with the lower X-axis to achieve a specified laser impact path, movement in the Y direction will also be performed.

[0053] The multi-axis collaborative structure of dual lead screws and gear rack in this embodiment can realize long-distance, high-precision transmission of large-size profiles and reduce curvature deviation in different profile areas.

[0054] It should be noted that in this embodiment, the drive motor controllers of the gear and rack transmission mechanism, the first lead screw transmission mechanism, and the second lead screw transmission mechanism are all connected to or communicate with the main control system and are subject to unified coordination and control by the main control system to achieve closed-loop control of the processing process.

[0055] In this embodiment, the worktable possesses sufficient strength and stability to support large-sized, complex, multi-cavity aluminum profiles; an adjustable clamp 10 is provided on the side of the worktable, combined with... Figure 4 The adjustable clamp 10 includes a pressure plate 22 and a telescopic structure 23. The telescopic structure 23 is an arc-shaped structure, with one end fixed to the worktable and the other end fixed to the pressure plate 22. The telescopic structure is a stackable structure, allowing for stacking and extension. The structure is flexible in deformation and can adapt to clamping profiles of different thicknesses. During deformation, the structure maintains central symmetry to ensure uniform force distribution. Specifically, in conjunction with... Figure 5 The telescopic structure includes multiple V-shaped support members 25, which are flexible connecting and deformable components. Adjacent V-shaped support members are hinged together by a flat plate 24, forming a foldable and extendable linkage. When the telescopic structure extends, the included angle of the V-shaped support members increases, unfolding in a petal shape. When it retracts, the included angle of the V-shaped support members decreases, stacking into a compact structure. Before placing profiles or other workpieces, the pressure plate is raised, applying a reverse compressive force to the telescopic structure, reducing the included angle of the V-shaped support members and stacking into a compact shape. After placing the profiles, the pressure plate needs to be pressed onto the surface of the workpiece and tightened with bolts. The included angle of the V-shaped support members increases, and the whole structure unfolds from a compact stacked state to expand the coverage space. At the same time, the telescopic structure can adapt to the clamping of profiles of different thicknesses.

[0056] The pressure plate 22 is set along the length of the workbench, and multiple fastening bolts 9 are provided on the pressure plate. The large-sized complex multi-cavity aluminum alloy profile to be processed is placed stably on the workbench, and then the pressure plate is set along the length of the profile on one side edge of the upper surface of the profile. It is fastened by adjusting the screws to ensure that the profile will not be displaced or shaken during subsequent movement. Considering the length of the aluminum alloy profile, a set of fastening bolts is placed at a certain distance (e.g., 1.5 meters).

[0057] This embodiment uses an adjustable fixture to replace the rigid mold. By flexibly adjusting the height of the pressure plate, it can adapt to the complex cross-section and length of multi-cavity profiles, saving the cost of custom molds and shortening the debugging cycle.

[0058] In this embodiment, the sealing device is set at both ends of the workbench along its length. The sealing device 3 and the workbench 4 may not be connected. After the workpiece to be processed is placed on the workbench and clamped, the sealing device is installed at both ends of the workpiece to be processed.

[0059] Combination Figure 6 The sealing device 3 uses a lightweight and high-strength aluminum alloy frame. The aluminum alloy frame 26 is rectangular, which is adapted to the square cross-section of the workpiece to be formed. The structure of the workpiece to be formed is as follows: Figure 8 As shown, an installation groove 27 is provided on the edge of the aluminum alloy frame 26 for installing sealing elements; both ends of the workpiece 5 to be formed extend into the sealing device and are sealed by the sealing elements; in this embodiment, a double-lip sealing ring 28 is used. When the square cross-section object is bent and deformed, the double-lip sealing ring 28 can deform accordingly by its own elasticity and always keep in close contact with the deformed square cross-section surface.

[0060] The sealing device is equipped with a pipe connected to an external source. This pipe is tightly connected to a liquid filling device for injecting a liquid at a set pressure into the cavities of the multi-cavity aluminum alloy profile within the sealing device. The liquid can be an emulsion, water-based hydraulic fluid, or high-purity deionized water, etc. The liquid filling device includes a hydraulic system 18 and a pipe 20 connected to the sealing device. The hydraulic system 18 includes a reservoir and a hydraulic pump. The hydraulic pump pumps the liquid in the reservoir into the sealing device through the pipe, ensuring the liquid evenly enters the cavities of the multi-cavity aluminum alloy profile. Simultaneously, the hydraulic system is equipped with a pressure regulating valve for overflow and pressure relief. An oil-water medium pressure sensor 19 is installed near the cavity of the profile within the sealing device. The oil-water medium pressure sensor 19 reads the internal liquid pressure of the profile in real time. When the internal pressure fluctuates, the pressure regulating valve controls the internal liquid pressure, allowing the liquid to be quickly discharged when the profile is compressed, thus maintaining a stable internal liquid pressure during laser impact. The adaptive double-lip seal can conform to the deformation of the profile, thus ensuring synchronous pressure control in multiple cavities and solving the problem of uneven pressure in conventional liquid-filled multi-cavity systems.

[0061] In this embodiment, a liquid filling device is used to fill the profile with liquid at a certain pressure before laser impact. At the same time, the liquid pressure is kept constant during laser impact. The liquid can flexibly support the cavity during laser impact and play a role in transmitting force in the cavity. When one side of the profile is impacted by the laser, the opposite side can also be subjected to the force transmitted by the liquid. This can ensure that the stress on all parts of the profile is uniform, avoid collapse, reduce the cross-sectional distortion rate, avoid cracking, wrinkling and other problems that are prone to occur during the forming of complex profiles, and improve forming accuracy.

[0062] It should be noted that in this embodiment, the hydraulic pump, pressure sensor, and pressure regulating valve are all connected to the main control system 21. The pressure sensor transmits the pressure detected in the cavity to the main control system 21. The main control system compares the received pressure with the preset target pressure, and then controls the operation of the pressure regulating valve and the hydraulic pump to achieve closed-loop pressure control.

[0063] In this embodiment, the laser emitting device includes: a laser 14 emitting a laser with a set energy, the laser beam being reflected multiple times by a reflector 13 to change the beam direction, and finally being focused onto the workpiece to be formed by a focusing lens 12.

[0064] The essence of laser shock forming is that laser energy is converted into plasma shock waves, which drive the plastic deformation of the profile. The laser focal length directly determines the size of the focused spot on the profile surface, and thus the energy density. A larger focal length will increase the spot area and decrease the energy density, which may result in insufficient plasma shock wave intensity and insufficient profile deformation force. A smaller focal length will reduce the spot area and result in excessively high energy density, which may lead to local energy concentration, making the profile surface prone to ablation, microcracks, or even penetration of the black tape absorption layer, directly damaging the profile substrate. If the focal length changes repeatedly during processing, the energy density will fluctuate, causing the deformation in different areas of the profile to become disordered and the cross-sectional distortion rate to increase, making it impossible to meet the requirements of high precision and consistent forming of large-size profiles.

[0065] In this embodiment, a laser rangefinder 32 is installed on the same reference plane P31 at the laser output port 30. Its function is to accurately measure the distance between the laser impact point and the preset reference plane. Figure 9 The positional relationship between the laser impact point A29 and the reference surface P31 can be observed. The measured distance is compared with the set laser focal length. Based on the comparison results, the height of the worktable is adjusted, thereby adjusting the distance between the laser impact point and the reference surface, so as to ensure that the laser focal length remains unchanged during the laser impact forming process.

[0066] In this embodiment, during laser shock forming, the water-spraying robot 15 moves the water spray nozzle to the forming processing position according to a preset program, and then water is sprayed from the nozzle to form a constraint layer. At the same time, the laser emits light. During the forming process, the water-spraying robot 15 adjusts the water spraying angle according to the position characteristics of the forming area. After the processing is completed, the water-spraying robot returns to the initial position, the water spray nozzle stops spraying water, and the laser stops emitting light.

[0067] The water confinement layer restricts the upward expansion of plasma, forcing the shock wave to propagate downwards and subjecting the material surface to higher compressive stress. Simultaneously, the laser energy is absorbed by the water and converted into heat, reducing direct thermal damage to the material surface and improving strengthening efficiency. Water's excellent thermal conductivity allows for rapid dissipation of laser energy, preventing localized overheating and facilitating precise control of impact depth and residual compressive stress layer distribution.

[0068] The laser rangefinder 32 is connected to or communicates with the main control system 21, transmitting the detected distance data to the main control system 21. The main control system 21 adjusts the movement of the first lead screw transmission mechanism according to the preset target distance to realize the lifting control of the worktable, thereby ensuring that the distance between the laser impact point and the preset reference surface remains stable.

[0069] In this embodiment, an automatic black tape application device 17 is also included to automatically apply black tape to the surface of the profile; combined with Figure 10 The automatic black tape applicator includes a robotic arm 16, a robotic arm connecting platform 33, a black tape mounting mechanism 34, a tape guiding assembly 35, and a pressure roller 36. The top of the robotic arm connecting platform is connected to the robotic arm, and the tape guiding assembly and the pressure roller are connected to opposite sides of the bottom, respectively. The tape mounting mechanism is located above the pressure roller, and the black tape is fixed on the tape mounting mechanism. Under the guidance of the tape guiding assembly, the robotic arm drives the tape guiding assembly and the pressure roller to move forward along a preset trajectory through the robotic arm connecting platform. First, the end of the black tape passes under the pressure roller and is pasted onto the workpiece to be formed. During the movement, the black tape is continuously released and pressed and pasted onto the surface of the workpiece by the pressure roller.

[0070] The robotic arm connection platform 33 serves as the core of the device's movement and positioning. Connected to the robotic arm 16 and controlled by the main control system, it can move precisely along the length or width of the profile, causing the entire mechanism to adjust its position according to the profile's contour. The black tape installation mechanism 34 is used to fix the black tape roll, providing a stable tape release source to ensure that the tape can be pulled out at a uniform speed during the pasting process, avoiding tape feeding jams caused by loose tape rolls. The tape guide assembly 35 consists of guide wheels and guide plates, used to guide the tape release path. The pressure roller 36 is made of elastic material and is installed below the guide assembly, rolling in contact with the profile surface. Through its own pressure, it tightly presses the pulled-out black tape onto the profile surface, eliminating air bubbles between the tape and the profile and preventing wrinkles.

[0071] Place the aluminum alloy profile on the workbench, install the black tape roll on the tape installation mechanism, and place the automatic black tape pasting device above the profile via a robotic arm. First, pass one end of the black tape through the pressure roller and paste it to one end of the workpiece. Control the robotic arm to descend so that the pressure roller is pressed tightly against the surface of the workpiece. Under the control of the main control system, the robotic arm moves slowly laterally so that the tape can be pulled out smoothly. At the same time, check the flexibility of the pressure roller. The pressure roller can evenly press the black tape onto the surface of the profile to ensure that there are no bubbles or wrinkles.

[0072] Compared to existing technologies where manual application of black tape is prone to misalignment and wrinkles, affecting energy absorption and surface quality, this embodiment achieves precise adhesion and eliminates air bubbles and wrinkles through an automatic black tape application device. Simultaneously, through robotic arm linkage, it seamlessly integrates with the laser impact process, reducing the time required for this step and improving efficiency.

[0073] Combination Figure 2 In this embodiment, the main control system enables centralized control of components such as the 3D scanner 11, laser, water-spraying robot, gear and rack transmission mechanism, first lead screw transmission mechanism, second lead screw transmission mechanism, robot arm, and hydraulic system in the liquid filling and laser shock composite forming system. The 3D scanner 11 is used to monitor the forming state of the workpiece and send the detection results to the main control system. The main control system controls the working parameters of each component according to the detection results to achieve closed-loop control of the entire processing process.

[0074] Addressing the technical challenges of traditional molding's reliance on molds, uncontrolled cavities from conventional laser shock, and the rough pressure control of conventional liquid filling, this embodiment utilizes the synergistic effect of innovative structures such as adjustable fixtures, multi-axis transmission, precise liquid filling and sealing, and intelligent measurement and control closed-loop systems. This eliminates mold costs, shortens the debugging cycle, improves curvature, cross-sectional accuracy, and surface quality, and simultaneously offers strong process adaptability, covering complex profiles with multiple specifications and curvatures, thereby increasing the workpiece qualification rate.

[0075] Example 2

[0076] In one or more embodiments, a liquid filling and laser shock composite forming method is disclosed, comprising the following process:

[0077] Curvature analysis was performed on the three-dimensional model of the target aluminum alloy profile to obtain the theoretical radius of curvature;

[0078] A three-dimensional model of an aluminum alloy profile with a proportional scale was established. The correspondence between liquid pressure and theoretical radius of curvature was obtained through data fitting, and the optimal liquid pressure and laser energy data were determined.

[0079] Determine the initial dimensions of the target aluminum alloy profile and complete the cutting process;

[0080] Seal and fix both ends of the target aluminum alloy profile, and automatically stick black tape on the surface of the target aluminum alloy profile to form an absorption layer;

[0081] A liquid with optimal pressure is injected into the target aluminum alloy profile, and laser energy is applied to the upper surface of the target aluminum alloy profile to perform laser impact forming. During the impact process, the liquid pressure inside the target aluminum alloy profile and the distance between the laser impact point and the preset reference surface are kept stable.

[0082] Specifically, the relationship between liquid pressure and radius of curvature was obtained through data fitting, as follows:

[0083] ;

[0084] Where R is the radius of curvature. For liquid pressure, Where L is the arc height value, and L is the length of the aluminum alloy profile plate; , Laser energy, The pulse width. The radius of the light spot is... This is the ratio of plasma thermal energy to internal energy, and is a set value.

[0085] After the impact is completed, the target aluminum alloy profile is scanned using a 3D scanner 11. The actual radius of curvature is compared with the theoretical radius of curvature. If the error exceeds the allowable range, it is corrected. If the error is within the allowable range, the liquid in the target aluminum alloy profile is extracted and recovered, the profile part connected to the sealing device is cut off, and then the cut profile is cleaned and polished to complete the processing.

[0086] As a specific implementation method, combined with Figure 11 The specific implementation process of the liquid filling and laser shock composite forming method in this embodiment is as follows:

[0087] S101: Use analysis software (such as UG software) to perform curvature analysis on the target 3D model to obtain the theoretical radius of curvature.

[0088] Specifically, the target 3D model of the aluminum alloy profile to be formed, i.e., the final shape model to be achieved, is obtained and imported into UG software; curvature analysis is performed on the target 3D model using UG, showing that the radius of curvature of the surface in the U direction is R. U If the measured angle between the U-direction and the principal plane is... Then the theoretical radius of curvature R is: .

[0089] S102: Use ABAQUS software to create a scaled-down 3D model of the aluminum alloy profile, perform numerical simulation analysis on it, and determine process parameters such as liquid pressure, laser energy, laser pulse width, and impact path.

[0090] Specifically, since the calculation of directly simulating large-sized profiles is too large, a scaled-down model is adopted (it is necessary to ensure that the material properties and cavity structure are consistent with the actual profiles).

[0091] This embodiment uses simulation data of liquid pressure and radius of curvature obtained from finite element analysis to perform data fitting, thereby obtaining the liquid pressure. and radius of curvature The relationship is:

[0092] ;

[0093] In the formula: The value of the arc height is expressed as follows: ; Laser energy, ; The pulse width. ; The radius of the light spot is... ; This is the ratio of plasma thermal energy to internal energy, generally between 0 and 1. The value varies for different materials, and for aluminum alloy profiles, the value is generally 0.274. For aluminum alloy profiles, .

[0094] The above correspondence was obtained through finite element simulation analysis of the profile deformation under different liquid pressure conditions:

[0095] When the liquid pressure is too low, the supporting force inside the cavity is insufficient. When the laser impacts the material, the lower surface (non-impact surface) of the profile will be concave, the cavity will collapse, and the curvature will be much greater than the theoretical value.

[0096] When the liquid pressure is too high, it exceeds the bearing limit of the profile sidewall, causing the cavity sidewall to bulge outward, the deformation direction to deviate from the theoretical curvature, and even damage the sealing device.

[0097] When the liquid pressure is optimal, the profile deforms to fit the theoretical curvature, and the cavity does not collapse or bulge.

[0098] It should be noted that the above relationship is based on simulation data (liquid pressure). With radius of curvature The mathematical fitting of discrete points aims to minimize the error between the calculated and simulated values, forming the input. and The mapping relationship is such that the formula only considers the numerical values ​​of each parameter and does not consider the units. As long as the units of the input data are consistent with the units of the data during fitting, the mathematical laws in the simulation data can be reproduced through the formula.

[0099] Based on the calculated theoretical radius of curvature, the optimal liquid pressure can be obtained, and then the optimal laser shock energy can be determined by controlling the variable method according to the liquid pressure.

[0100] Current technologies often determine liquid pressure through trial and error or simple theoretical estimation. The trial-and-error method relies on human experience, leading to significant variations between different operators and equipment. The simplified theoretical method fails to consider the geometric characteristics of the profile (e.g., plate length affects pressure distribution), resulting in large deviations between pressure settings and actual requirements, and low accuracy in curvature control. Furthermore, the determination process requires multiple trial runs and pressure adjustments (especially for large, complex profiles), which is time-consuming, labor-intensive, and results in a long development cycle. For new profile specifications (e.g., different plate lengths), there is no universal formula to guide pressure setting, requiring repeated trial and error, making it difficult to quickly respond to customized needs.

[0101] Compared to existing technologies that determine liquid pressure through empirical trial and error or simple theoretical estimation, this embodiment establishes the liquid pressure... and radius of curvature The corresponding mapping relationship between them allows the liquid pressure to be directly calculated by inputting the theoretical radius of curvature, which can improve efficiency, reduce costs, and adapt to multi-cavity aluminum alloy profiles of different specifications. At the same time, it can adjust the liquid pressure in real time according to the changes in parameters, solving the problems of complex pressure setting process and low accuracy in traditional methods, and providing key technical support for the forming of large-size complex aluminum profiles.

[0102] S103: Use Solidworks software to flatten the workpiece model, obtain the initial structural dimensions of the workpiece, and cut the material according to the unfolded boundary. The actual cutting size should be larger than the theoretical size. After processing, the workpiece connected to the sealing device should be cut off. After cutting, the workpiece surface should be pre-treated.

[0103] S104: Place the aluminum alloy profile on the movable workbench, and place the automatic black tape applicator above the profile via a robotic arm. The robotic arm moves slowly laterally via a controller, and the automatic applicator pulls out the black tape. The pressure roller then firmly adheres the black tape to the surface of the profile, ensuring that there are no bubbles or wrinkles.

[0104] S105: Connect the sealing device to both ends of the aluminum alloy profile, and introduce liquid of a certain pressure determined in step S102 into the cavity through the liquid filling device. Start all transmission devices and perform impact forming according to the laser processing parameters determined in step (2). Perform laser impact forming on the upper surface of the aluminum alloy profile, and the opposite side is subjected to the force transmitted by the liquid, so that the aluminum alloy profile achieves the ideal forming accuracy.

[0105] S106: The internal liquid pressure of the profile is read in real time by an oil-water medium pressure sensor, and the internal liquid pressure is controlled by a pressure regulating valve to maintain a stable liquid pressure in the profile cavity during laser impact.

[0106] S107: During the processing, the laser rangefinder detects the focal length of the laser impact. If the distance changes, the laser rangefinder transmits the signal to the main control system. The main control system controls the first lead screw transmission mechanism to raise and lower the worktable to ensure that the laser focal length remains unchanged during the laser impact forming process.

[0107] S108: After the impact is completed, the aluminum alloy profile is scanned using a 3D scanner to compare the actual radius of curvature with the theoretical radius of curvature. If the error is large, correction is performed, i.e., another laser impact is performed according to the determined parameters. If it is within the allowable error range, the liquid in the aluminum alloy profile is recovered into the hydraulic pump, the part of the workpiece connected to the sealing device is cut off, and then the profile is cleaned and polished to complete the processing.

[0108] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for liquid filling and laser shock lithography composite forming, characterized in that, The liquid filling and laser shock hybrid forming system includes: a laser emitting device, a liquid filling device, and a workpiece platform; the workpiece platform includes a base, a worktable on the base, and adjustable clamps on the side of the worktable for clamping the workpiece to be formed; sealing devices are provided at both ends of the worktable for sealing both ends of the workpiece to be formed; the sealing devices are connected to the liquid filling device through pipes, and the liquid filling device is used to fill the cavity of the workpiece to be formed with liquid at a set pressure, which is connected to the sealing device; the laser emitting device is used to emit a laser beam at the workpiece to be formed, and a laser rangefinder is used to detect the distance between the laser impact point and a preset reference surface in real time, compare the distance with the set distance, and adjust the position of the worktable according to the distance deviation; The method includes: performing curvature analysis on a three-dimensional model of the target aluminum alloy profile to obtain the theoretical radius of curvature; A three-dimensional model of an aluminum alloy profile with a proportional scale was established. The correspondence between liquid pressure and theoretical radius of curvature was obtained through data fitting, and the optimal liquid pressure and laser energy data were determined. Determine the initial dimensions of the target aluminum alloy profile and complete the cutting process; Seal and fix both ends of the target aluminum alloy profile, and automatically stick black tape on the surface of the target aluminum alloy profile to form an absorption layer; A liquid with optimal pressure is injected into the target aluminum alloy profile, and laser energy is applied to the upper surface of the target aluminum alloy profile to perform laser impact forming. During the impact process, the liquid pressure inside the target aluminum alloy profile and the distance between the laser impact point and the preset reference surface are kept stable.

2. The liquid filling and laser shock composite forming method as described in claim 1, characterized in that, A rack is set along a preset direction, and a base is set above the rack and connected to the rack via gears; rotation of the gears can drive the base to move on the rack; a first lead screw transmission mechanism is set on the base along the vertical direction, and the first lead screw transmission mechanism is connected to the worktable, which can move along the vertical direction under the drive of the first lead screw transmission mechanism; a second lead screw transmission mechanism is set along the direction perpendicular to the rack, and the second lead screw transmission mechanism is connected to the rack, which, together with the base and the worktable on it, can move under the drive of the second lead screw transmission mechanism.

3. The liquid filling and laser shock composite forming method as described in claim 1, characterized in that, The adjustable clamp includes a pressure plate and a telescopic structure. One end of the telescopic structure is fixed to the workbench and the other end is fixed to the pressure plate. The pressure plate is arranged along the length of the workbench and is provided with multiple fastening bolts.

4. The liquid filling and laser shock composite forming method as described in claim 1, characterized in that, The shape of the sealing device is adapted to the cross-sectional shape of the workpiece to be formed, and the sealing device is provided with a double-lip seal to achieve a seal between the sealing device and the workpiece to be formed.

5. The liquid filling and laser shock composite forming method as described in claim 4, characterized in that, The sealing device is equipped with a pressure sensor to detect the liquid pressure in the cavity of the workpiece to be formed; the liquid filling device includes a hydraulic pump and a pressure regulating valve, which controls the liquid pressure in the cavity of the workpiece to be formed to remain stable.

6. The liquid filling and laser shock blasting composite forming method as described in claim 1, characterized in that, Also includes: An automatic black tape pasting device includes: a robot arm connecting platform, a tape mounting mechanism, a tape guiding component, and a pressure roller; the top of the robot arm connecting platform is connected to the robot arm, and the tape guiding component and the pressure roller are respectively connected to opposite sides of the bottom; the tape mounting mechanism is located above the pressure roller; the black tape is placed on the tape mounting mechanism, and under the guidance of the tape guiding component, the robot arm drives the tape guiding component and the pressure roller to move forward along a preset trajectory through the robot arm connecting platform; first, the end of the black tape passes under the pressure roller and is pasted onto the workpiece to be formed; during the movement, the black tape is continuously released and pressed and pasted onto the surface of the workpiece by the pressure roller.

7. A liquid filling and laser shock blasting composite forming method as described in any one of claims 1-6, characterized in that, Also includes: The main control system is used to realize closed-loop operation control of the laser emitting device and the liquid filling device, as well as the movement control of the working platform.

8. The liquid filling and laser shock composite forming method as described in claim 1, characterized in that, The relationship between liquid pressure and radius of curvature was obtained through data fitting, specifically: ； Where R is the radius of curvature. For liquid pressure, Where L is the arc height value, and L is the length of the aluminum alloy profile plate; , Laser energy, The pulse width. The radius of the light spot is... This is the ratio of plasma thermal energy to internal energy, and is a set value.

9. The liquid filling and laser shock blasting composite forming method as described in claim 1, characterized in that, Also includes: After the impact is completed, the target aluminum alloy profile is scanned using a 3D scanner. The actual radius of curvature is compared with the theoretical radius of curvature. If the error exceeds the allowable range, it is corrected. If the error is within the allowable range, the liquid in the target aluminum alloy profile is extracted and recovered. The profile part connected to the sealing device is cut off. Then the cut profile is cleaned and polished, and the processing is completed.

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