An ultrasonic-assisted laser shock forming method and system for aluminum alloy plate

Abstract

The application provides an ultrasonic-assisted laser shock forming method and system for an aluminum alloy plate, and comprises the following steps: dividing the surface of the aluminum alloy plate into an inner concave surface and an outer convex surface according to bending forming requirements of the plate; impacting the inner concave surface by using a pulsed laser beam, and assisting in applying ultrasonic shock waves to the outer convex surface at a position corresponding to the laser impact; and synchronously moving the pulsed laser beam and the ultrasonic shock waves according to a moving path to obtain an aluminum alloy plate with a bending curvature. The application realizes flexible dieless forming of the aluminum alloy plate by using ultrasonic-assisted laser shock forming technology. The acoustic softening effect caused by high-frequency vibration of the ultrasonic shock can effectively improve the plastic forming capacity of the aluminum alloy plate, and realize macroscopic plastic forming of the high-strength aluminum alloy plate by laser impact.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of metal sheet forming processing, and particularly relates to an ultrasonic-assisted aluminum alloy sheet laser shock forming method and system. BACKGROUND

[0002] Aluminum alloy is widely used in the field of high-speed rail and aircraft manufacturing industry due to its high strength, good toughness and plasticity, and excellent mechanical and processing performance, such as aircraft skin and high-speed rail carriages. With the development and progress of equipment, in order to meet the high-performance use requirements of equipment, the manufacturing requirements of complex curved surfaces of aluminum alloy sheets are increasing.

[0003] Current cold stamping forming is the main method to realize metal sheet forming, and has high production efficiency and is suitable for mass production. However, the forming technology has high requirements for the precision of the die, and the manufacturing process of the die is complex, long in cycle and expensive, which limits the application of this method in the production of small batch parts. Cold stamping forming is only suitable for the forming of metal sheets with good plasticity such as low-carbon steel and aluminum-copper alloy, and is not suitable for the forming of high-strength metal sheets such as hard aluminum alloy. In addition, cold stamping forming is also difficult to realize the forming of sheets with special curvature requirements, and is prone to defects such as tensile cracks, which affects the service life of the formed components. Therefore, the traditional processing method is often difficult to meet the requirements of current high-precision sheet forming, and it is necessary to find an advanced flexible precision forming technology to realize the rapid and efficient forming of aluminum alloy sheets, which has important significance.

[0004] Laser forming technology is a new type of metal forming technology, which overcomes the shortcomings of poor flexibility, high mold cost and long production cycle of traditional forming process, and shows a wide application prospect in many fields such as automobile, aviation and national defense industry. Among them, laser shock forming (LSF) has the characteristics of ultra-high pressure, high energy and high strain rate, and is a composite forming technology integrating material modification and strengthening and forming. Its principle is to use the mechanical effect of high-energy short-pulse laser and material interaction to induce high-amplitude shock wave or stress wave to promote the macroscopic plastic deformation of the sheet. By selecting appropriate laser pulse energy, pulse width, spot size and overlap rate, the ideal sheet deformation can be obtained; by setting appropriate forming trajectory, impact area and pulse number, local or large-area forming of sheet can be realized. For hard aluminum alloy, the plastic deformation of sheet formed by single laser shock is very small, and the forming efficiency is low, which is difficult to adapt to the large-area macroscopic forming of high-strength aluminum alloy sheet, which greatly limits the effective application of laser shock forming technology in the field of sheet forming. Therefore, it is necessary to improve the laser shock forming technology. For example, the prior art discloses a sheet forming method and device, which uses CO2 continuous laser to heat pretreat the sheet to improve the plastic forming ability of the sheet and increase the deformation of the sheet in laser shock forming. The disadvantage of this method is that the laser heating temperature is high, which is easy to cause thermal damage to the sheet, and the heating is uneven, and the stress distribution is difficult to control, which will form harmful residual tensile stress on the surface of the sheet. For another example, the prior art discloses a multi-point laser shock forming device and forming method, which uses several independent single pulse lasers for multi-point synchronous laser shock forming, effectively avoids the fracture damage phenomenon easily caused by single spot shock forming, significantly improves the processing efficiency of laser shock forming, and easily realizes the precise forming of complex surface. But the multi-pulse laser works together, the cost of this processing method is too high, and it has great limitations in actual production, and the lack of overlap rate makes it difficult to eliminate the concave-convex marks formed by single-point laser shock, and the surface quality of the formed workpiece is poor. SUMMARY

[0005] In view of the deficiencies in the prior art, the present application provides an ultrasonic-assisted aluminum alloy sheet laser shock forming method and system, which realizes flexible dieless forming of aluminum alloy sheets by using ultrasonic-assisted laser shock forming technology. The acoustic softening effect caused by ultrasonic shock high-frequency vibration can effectively improve the plastic forming ability of aluminum alloy sheets, realizing macroscopic plastic forming of high-strength aluminum alloy sheets by laser shock. At the same time, the ultrasonic effect effectively enhances the ability of laser shock to induce dynamic recrystallization in the substrate material, and effectively regulates the stress generated by the plasma shock wave in the substrate material, so that the mechanical gain of the material caused by laser shock can be further enhanced. In addition, the coupling mechanism of high-frequency vibration caused by ultrasonic shock and ultrahigh strain rate caused by laser shock can effectively reduce the surface defects of the laser shock formed workpiece, and the surface quality of the aluminum alloy sheet is also improved while realizing macroscopic plastic forming.

[0006] The present application realizes the above technical object through the following technical means.

[0007] An ultrasonic-assisted aluminum alloy sheet laser shock forming method, comprising the following steps:

[0008] According to the bending forming requirements of the sheet, the surface of the aluminum alloy sheet is divided into an inner concave surface and an outer convex surface;

[0009] The inner concave surface is impacted by a pulsed laser beam, and an ultrasonic shock wave is applied to the outer convex surface at the corresponding position of the laser impact;

[0010] The pulsed laser beam and the ultrasonic shock wave are synchronously moved according to the advancing path to obtain an aluminum alloy sheet with a bending curvature.

[0011] Further, the method further comprises the following step: pretreating the surface of the aluminum alloy sheet to make the surface roughness value ≤5µm.

[0012] Further, the surface of the aluminum alloy sheet is pretreated, specifically: the surface of the sheet is polished after being ground by sandpaper with different particle sizes, and the treated surface is ultrasonically cleaned with anhydrous ethanol solution and dried.

[0013] Further, an absorption layer and a flow water constraint layer are coated on the inner concave surface, the thickness of the absorption layer is 40-60μm, and the thickness of the flow water constraint layer is about 2mm.

[0014] Further, in the advancing path, the pulsed laser beam acts vertically on the inner concave surface, and the ultrasonic shock wave acts vertically on the outer convex surface.

[0015] Further, the pulse laser beam is generated by a nanosecond pulse laser, the spot diameter of the pulse laser beam is 3-10 mm, the pulse frequency of the pulse laser beam is 1-10 Hz, the pulse width of the pulse laser beam is 10-20 ns, the pulse energy of the pulse laser beam is 3-20 J, and the spot overlap rate of the pulse laser beam is 20%-80%.

[0016] Further, the ultrasonic shock wave is generated by an ultrasonic generator, the vibration frequency of the ultrasonic shock wave is 20-40 kHz, the amplitude of the ultrasonic shock head of the ultrasonic generator is 20-100 mu m, and the diameter of the ultrasonic shock head is 3-10 mm.

[0017] An ultrasonic-assisted aluminum alloy sheet laser shock forming method system, comprising an ultrasonic generator, a pulse laser, and a controller; the ultrasonic generator is used to generate an ultrasonic shock wave, and the pulse laser is used to generate a pulse laser beam.

[0018] The pulse laser beam acts on the inner concave surface of the aluminum alloy sheet, and the ultrasonic shock wave acts on the outer convex surface of the aluminum alloy sheet at the corresponding position of the laser shock;

[0019] The controller controls the ultrasonic shock wave and the pulse laser beam to move synchronously.

[0020] The beneficial effects of the present application are that:

[0021] 1. The ultrasonic-assisted aluminum alloy sheet laser shock forming method of the present application can greatly reduce the flow stress and deformation resistance of the material in the impact area by using the high-frequency vibration generated by ultrasonic impact, so that the material has good plastic deformation ability, and the forming limit of the laser-impacted aluminum alloy sheet is improved; at the same time, the ultrasonic impact stress bending forming mechanism can effectively reduce the energy required for laser shock forming, improve the laser shock forming efficiency, increase the deformation amount of the single laser-impacted plastic forming sheet, and expand the application of laser shock in the forming field of high-strength aluminum alloy sheets.

[0022] 2. The ultrasonic-assisted laser shock forming method for aluminum alloy plate material according to the present application, the high-frequency vibration induced by ultrasonic impact promotes the periodic densification and loosening of atomic lattice, promotes the rapid transformation of microstructure such as dislocation cell and dislocation wall to low-energy state during the propagation of laser shock wave, and makes subgrain boundary and high-angle grain boundary form, so that the dynamic recrystallization ability is improved, the grain inside the matrix material is induced to be more refined, the dislocation density is higher, the residual compressive stress amplitude is larger, and the beneficial influence layer thickness is deeper, thereby effectively enhancing the strengthening effect of laser shock on the material; the addition of the ultrasonic field can also effectively reduce the pit depth generated on the surface of the plate material by laser impact, improve the precision of the surface of the formed plate material, and effectively improve the uneven distribution of residual stress in the surface layer and depth direction of the matrix, realize beneficial regulation of the stress inside the matrix material, and improve the mechanical properties and service life of the formed aluminum alloy plate material.

[0023] 3. The ultrasonic-assisted laser shock forming method for aluminum alloy plate material according to the present application, the coupling effect of ultrahigh strain rate generated by laser impact and high-frequency vibration generated by ultrasonic impact reduces the dislocation activation energy and reduces the influence of dislocation pinning, reduces the stress rebound amount of plate forming, and improves the forming precision and efficiency of the aluminum alloy plate material; the ultrasonic impact and laser impact process parameters are accurately controllable, and all process parameters can be set in the computer, which is easy to realize large-scale industrial production and has a wide industrial application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. The drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0025] Figure 1 The ultrasonic-assisted laser shock forming method for aluminum alloy plate material according to the present application.

[0026] Figure 2 The ultrasonic-assisted laser shock forming method for aluminum alloy plate material according to the present application.

[0027] Figure 3 The actual forming effect of the aluminum alloy plate according to the first embodiment of the present application.

[0028] Figure 4 The profile of the formed aluminum alloy plate according to each embodiment of the present application.

[0029] Figure 5 The surface hardness of the formed aluminum alloy plate according to each embodiment of the present application.

[0030] Figure 6 A residual stress map of a shaped aluminum alloy plate according to an embodiment of the present invention.

[0031] In the drawings:

[0032] 1 - pulsed laser beam; 2 - ultrasonic shock wave; 3 - ultrasonic shock head; 4 - absorption layer; 5 - water outlet; 6 - concave inner surface; 7 - convex outer surface. DETAILED DESCRIPTION

[0033] The present invention will be further described with reference to the drawings and specific examples, but the scope of the present invention is not limited thereto.

[0034] Embodiments of the present invention are described in detail below with reference to the drawings, in which examples of the embodiments are shown in the drawings, wherein the same or similar notations are used to denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present invention, and cannot be understood as limiting the present invention.

[0035] In the description of the present invention, it needs to be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "axial", "radial", "vertical", "horizontal", "inner", "outer" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can be explicitly or implicitly included one or more of the features. In the description of the present invention, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0036] In the present invention, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present invention can be understood according to the specific circumstances.

[0037] As Figure 1 shown, the ultrasonic-assisted aluminum alloy plate laser shock forming method according to the present invention comprises the following steps:

[0038] The surface of the aluminum alloy plate is polished by sandpaper with different particle sizes to make the surface roughness value ≤5 µm, and the treated plate surface is placed in anhydrous ethanol solution for ultrasonic cleaning, and then dried for standby;

[0039] The surface of the aluminum alloy plate is polished by sandpaper with different particle sizes to make the surface roughness value ≤5 µm, and the treated plate surface is placed in anhydrous ethanol solution for ultrasonic cleaning, and then dried for standby;

[0040] The pulse laser beam 1 and the ultrasonic impact wave 2 are moved synchronously according to the advancing path, the pulse laser beam 1 is kept vertical to the inner concave surface 6, and the ultrasonic impact wave 2 is kept vertical to the outer convex surface 7, so that the aluminum alloy plate with bending curvature is obtained.

[0041] The ultrasonic auxiliary aluminum alloy plate laser impact forming method provided by the application is a dieless forming method of high-strength aluminum alloy plate, and ultrasonic impact is introduced to assist aluminum alloy plate forming in the laser impact forming process. The high-frequency vibration generated by ultrasonic impact can effectively reduce the deformation resistance and deformation resistance of the material and improve the plastic forming capacity of the plate. The formed aluminum alloy material prepared by the laser impact process under the assistance of ultrasonic impact has a more effective grain refinement and a uniform residual compressive stress affected layer, which significantly improves the mechanical properties and fatigue resistance of the formed workpiece. In addition, the addition of the ultrasonic field effectively suppresses the pit depth generated on the plate surface by laser impact, improves the quality of the formed plate surface, and the coupling of the ultrahigh strain rate of laser impact and the high-frequency vibration of ultrasonic impact reduces the dislocation activation energy of the material and weakens the dislocation pinning effect, reduces the springback amount of the plate forming stress, and improves the forming precision and efficiency of the aluminum alloy plate.

[0042] To make the purpose, technical scheme and advantages of the application more clear, the following describes the application in detail by selecting 2024 aviation aluminum alloy plate as the research object, combining with the drawings and three specific embodiments.

[0043] Example one:

[0044] The ultrasonic auxiliary aluminum alloy plate laser impact forming method of example one comprises the following specific steps:

[0045] (1) Use sandpaper with different particle sizes to polish the surface of a 2024 aviation aluminum alloy plate with a size of 40mm×20mm×1mm to make the surface roughness value ≤5 µm, and use anhydrous ethanol solution to ultrasonically clean the treated surface and dry it;

[0046] (2) Laser shock is performed by using a Nd:YAG high-repetition-rate high-energy nanosecond pulse laser, the laser pulse energy is 6 J, the spot diameter is 3 mm, the pulse frequency is 1 Hz, the pulse width is 10 ns, and the overlap rate is 50%, and 40 μm thick black paint is sprayed on the inner concave surface as an absorbing layer 4, and 2 mm of flowing water is used as a flowing water constraint layer;

[0047] (3) Ultrasonic shock is synchronously applied at the relative position of the laser shock on the aviation aluminum alloy plate, the diameter of the impact head is 3 mm, the working frequency is 20 kHz, and the amplitude is 20 μm, the pulse laser beam and the ultrasonic impact head are always vertically applied to the symmetrical positions of the two sides of the plate, the motion paths are coincident, and the laser shock and the ultrasonic shock have synchronicity, and the working paths of the laser shock and the ultrasonic shock are as shown in Figure 2

[0048] (4) Laser shock forming is performed on the aluminum alloy plate under the assistance of ultrasonic shock to obtain an aluminum alloy plate with a bending curvature.

[0049] The actual effect of the aviation aluminum alloy formed plate prepared in the embodiment one is as shown in Figure 3 , the profile curve of the aluminum alloy plate formed by different laser shock processes is as shown in Figure 4 , under the laser shock plastic forming mechanism, the maximum deformation depth of the formed aluminum alloy plate is only 1.78 mm, while the maximum deformation depth of the aluminum alloy plate formed by the ultrasonic assisted laser shock in the embodiment one is 2.83 mm, which is increased by about 59% compared with the maximum deformation depth of the aluminum alloy plate formed by single laser shock. This result shows that the ultrasonic shock effectively softens the matrix material and improves the plastic deformation capacity of the material, so that the laser shock obtains a larger plate deformation. The surface hardness of the formed aluminum alloy plate is as shown in Figure 5 , the surface hardness of the aluminum alloy plate formed by ultrasonic assisted laser shock is 189 HV, which is increased by about 45.4% compared with the surface hardness 130 HV of the untreated aluminum alloy plate, and is increased by about 13.2% compared with the surface hardness 167 HV of the aluminum alloy plate formed by single laser shock. The surface residual stress of the formed aluminum alloy plate is as shown in Figure 6 , the surface residual stress of the aluminum alloy plate formed by ultrasonic assisted laser shock in the embodiment one is -191 MPa, which is increased by about 16 times compared with the surface residual stress -11 MPa of the untreated aluminum alloy plate, and is increased by about 15.1% compared with the surface residual stress -166 MPa of the aluminum alloy plate formed by single laser shock, which greatly improves the service life of the aviation aluminum alloy formed component.

[0050] Embodiment two:

[0051] ​On the basis of embodiment one, the laser shock processing parameter in embodiment two is set as follows: laser pulse energy is 15 J, spot diameter is 5 mm, pulse frequency is 5 Hz, pulse width is 15 ns, and the overlap rate is 20%, and 50 μm thick black paint is sprayed on the side of laser shock forming as an absorption layer.

[0052] The ultrasonic auxiliary processing parameter in embodiment two is set as follows: working frequency is 30 kHz, amplitude is 50 μm, and the diameter of the impact head striker is 5 mm.

[0053] The deformation profile curve of the aviation aluminum alloy plate prepared in embodiment two is shown in Figure 4 As can be seen from the figure, the maximum deformation depth of the aluminum alloy plate formed by ultrasonic auxiliary laser shock in embodiment two is 3.41 mm, which is increased by about 20.5% compared with the maximum deformation depth 2.83 mm of the aluminum alloy plate formed by ultrasonic auxiliary laser shock in embodiment one. The surface hardness of the formed aluminum alloy plate in embodiment two is shown in Figure 5 As can be seen from the figure, the surface hardness of the formed aluminum alloy plate in embodiment two is 201 HV, which is increased by about 6.3% compared with the surface hardness 189 HV of the formed aluminum alloy plate prepared in embodiment one. The surface residual stress of the formed aluminum alloy plate prepared in embodiment two is shown in Figure 6 As can be seen from the figure, the surface residual stress of the formed aluminum alloy plate in embodiment two is -207 MPa, which is increased by about 8.4% compared with the surface residual stress -191 MPa of the formed aluminum alloy plate in embodiment one. Since larger laser shock and ultrasonic auxiliary processing parameters are used in embodiment two, the deformation, surface hardness and residual stress are effectively improved compared with those in embodiment one.

[0054] Embodiment three:

[0055] On the basis of embodiment one, the laser shock processing parameter in embodiment three is set as follows: laser pulse energy is 20 J, spot diameter is 10 mm, pulse frequency is 10 Hz, pulse width is 20 ns, and the overlap rate is 80%, and 60 μm thick black paint is sprayed on the side of laser shock forming as an absorption layer.

[0056] The ultrasonic auxiliary processing parameter in embodiment three is set as follows: working frequency is 40 kHz, amplitude is 70 μm, and the diameter of the impact head striker is 10 mm.

[0057] The deformation profile curve of the aviation aluminum alloy plate in embodiment three is shown in Figure 4 As can be seen from the figure, the maximum deformation depth of the aluminum alloy plate formed by ultrasonic auxiliary laser shock in embodiment three is 3.79 mm, which is increased by about 33.9% compared with the maximum deformation depth 2.83 mm of the aluminum alloy plate formed in embodiment one, and is increased by about 11.1% compared with the maximum deformation depth 3.41 mm of the aluminum alloy plate formed in embodiment two. As Figure 5As shown, the surface hardness of the formed aluminum alloy sheet prepared in Example Three is 203 HV, as shown in Figure 6 As shown, the surface residual stress of the formed aluminum alloy sheet prepared in Example Three is -206 MPa. Example Three further increases the process parameters of laser shock and ultrasonic assistance, and the surface hardness and residual stress of the formed sample are similar to those of Example Two due to the influence of saturation effect, but the maximum deformation depth of the formed sheet is better than that of Example One and Example Two, and a greater plastic deformation is obtained.

[0058] The system of the ultrasonic-assisted aluminum alloy sheet laser shock forming method described in the present application comprises an ultrasonic generator, a pulsed laser, and a controller; the ultrasonic generator is used to generate ultrasonic shock waves 2, and the pulsed laser is used to generate a pulsed laser beam 1;

[0059] The pulsed laser beam 1 acts on the inner concave surface 6 of the aluminum alloy sheet, and the ultrasonic shock waves 2 act on the outer convex surface 7 of the aluminum alloy sheet at the corresponding position of the laser shock; the water outlet 5 is located at the inner concave surface 6 for forming a flowing water constraint layer. The controller controls the synchronous movement of the ultrasonic shock waves 2 and the pulsed laser beam 1.

[0060] It should be understood that although the present specification is described in terms of various embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be combined appropriately to form other embodiments that those skilled in the art can understand.

[0061] The series of detailed descriptions listed above are only specific descriptions of the feasible embodiments of the present application, and are not intended to limit the protection scope of the present application, and any equivalent embodiments or changes made without departing from the spirit of the present application should be included in the protection scope of the present application.

Claims

1. An ultrasonic-assisted laser shock forming method for an aluminum alloy sheet, characterized by, It comprises the following steps: According to the bending forming requirements of the plate, the surface of the aluminum alloy plate is divided into an inner concave surface (6) and an outer convex surface (7); The inner concave surface (6) is impacted by a pulsed laser beam (1), and an ultrasonic impact wave (2) is applied at the corresponding position on the outer convex surface (7) to assist the laser impact; the high-frequency vibration generated by the ultrasonic impact wave (2) reduces the flow stress and deformation resistance of the material in the laser impact area, and the ultrasonic impact wave (2) reduces the energy required for laser impact forming; the high-frequency vibration induced by the ultrasonic impact wave (2) promotes the periodic densification and loosening of the atomic lattice in the aluminum alloy plate, promotes the transformation of dislocation cells and dislocation walls to a low-energy state during the propagation of the laser impact wave, and forms sub-grain boundaries and large-angle grain boundaries, thereby improving the dynamic recrystallization ability; the ultrasonic impact wave (2) reduces the pit depth generated by the pulsed laser beam (1) impacting the surface of the plate, thereby improving the precision of the formed plate surface; The pulsed laser beam (1) and the ultrasonic impact wave (2) are moved synchronously according to the travel path to obtain an aluminum alloy plate with a bending curvature.

2. The ultrasonic-assisted aluminum alloy sheet laser shock forming method according to claim 1, characterized by, It also comprises the following steps: pretreating the surface of the aluminum alloy plate to make the surface roughness value ≤5µm.

3. The ultrasonic-assisted aluminum alloy sheet laser shock forming method according to claim 2, characterized in that, The surface of the aluminum alloy plate is pretreated, specifically: the surface of the plate is polished after being ground by sandpaper with different particle sizes, and the treated surface is ultrasonically cleaned with anhydrous ethanol solution and dried.

4. The ultrasonic-assisted aluminum alloy sheet laser shock forming method according to claim 1, characterized by, An absorption layer (4) and a flowing water constraint layer are coated on the inner concave surface (6), the thickness of the absorption layer (4) is 40-60µm, and the thickness of the flowing water constraint layer is about 2mm.

5. The ultrasonic-assisted aluminum alloy sheet laser shock forming method according to claim 1, characterized by, In the travel path, the pulsed laser beam (1) acts vertically on the inner concave surface (6), and the ultrasonic impact wave (2) acts vertically on the outer convex surface (7).

6. The ultrasonic-assisted aluminum alloy sheet laser shock forming method according to claim 1, characterized by, The pulsed laser beam (1) is generated by a nanosecond pulsed laser, the spot diameter of the pulsed laser beam (1) is 3-10mm, the pulse frequency of the pulsed laser beam (1) is 1-10Hz, the pulse width of the pulsed laser beam (1) is 10-20ns, the pulse energy of the pulsed laser beam (1) is 3-20J, and the spot overlap rate of the pulsed laser beam (1) is 20%-80%.

7. The ultrasonic-assisted aluminum alloy sheet laser shock forming method according to claim 1, characterized by, The ultrasonic impact wave (2) is generated by an ultrasonic wave generator, the vibration frequency of the ultrasonic impact wave (2) is 20-40kHz; the amplitude of the ultrasonic impact head (3) of the ultrasonic wave generator ranges from 20 to 100µm, and the diameter of the striker ranges from 3 to 10mm.

8. A system for the ultrasonic-assisted laser shock forming of aluminum alloy sheets according to the method of any one of claims 1-7, characterized in that, It comprises an ultrasonic wave generator, a pulsed laser, and a controller; the ultrasonic wave generator is used to generate an ultrasonic impact wave (2), and the pulsed laser is used to generate a pulsed laser beam (1); The pulsed laser beam (1) acts on the inner concave surface (6) of the aluminum alloy plate, and the ultrasonic impact wave (2) acts on the outer convex surface (7) of the aluminum alloy plate at the corresponding position of the laser impact; The controller controls the synchronous movement of the ultrasonic impact wave (2) and the pulsed laser beam (1).

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