Dynamic spot shaping device, system and method for oblique incidence laser shock peening

Abstract

The application provides a spot dynamic correction device, system and method for oblique incidence laser shock peening, wherein the device comprises a base, a light beam shaping assembly arranged on one side of the base and used for receiving a light beam and generating a circular parallel light beam, a light beam correction assembly installed on the base and used for compressing the circular parallel light beam into an elliptical parallel light beam, the light beam correction assembly comprises a plano-convex cylindrical lens unit and a plano-concave cylindrical lens unit arranged in sequence, the plano-convex cylindrical lens unit is arranged on the light exit side of the light beam shaping assembly, the plano-concave cylindrical lens unit is arranged on the light exit side of the plano-convex cylindrical lens unit, and a light beam focusing assembly is arranged on the light exit side of the plano-concave cylindrical lens unit. The circular light beam is corrected into an elliptical parallel light beam through the light beam correction assembly, and the elliptical parallel light beam generates a circular spot on the surface of a part during oblique incidence laser shock peening, so that the strengthening effect is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser shock peening, and in particular to a spot dynamic correction device, system and method for oblique incidence laser shock peening. BACKGROUND

[0002] Laser shock processing (LSP) is a technique that uses a high-power density of GW / cm2 and a short pulse width of nanoseconds to irradiate a material surface with a strong laser, an absorption protective layer coated on the material surface absorbs the laser energy to cause explosive gasification and evaporation, forming a high-temperature (>10000℃) plasma, the plasma continues to absorb the laser energy to expand sharply, and under the constraint of water flow, a high-pressure (>1GPa) shock wave is formed to propagate to the inside of the material, the material is subjected to severe plastic deformation under the action of the high-pressure shock wave, residual stress is formed, the microstructure is changed, and the fatigue performance, wear and stress corrosion performance of the material are improved.

[0003] The fatigue danger area of an aircraft structure is usually at the root R of a frame, beam or wall, and the area is blocked and has limited opening conditions. When laser shock peening is performed, the laser incidence direction cannot be guaranteed to be consistent with the normal line of the part strengthening surface, at which time spot distortion occurs, forming an elliptical impact spot. When the oblique incidence angle is too large, the spot distortion is serious, and the strengthening effect is reduced. In addition, due to the blocking and other reasons, it is usually not possible to use the same incidence angle to complete the processing of the area to be strengthened. The impact spot distortion degree of the strengthening area is different, and it is difficult to form a uniform residual compressive stress field, thereby reducing the gain effect of the fatigue performance after strengthening.

[0004] At present, in order to solve the problem of reduced strengthening effect caused by spot distortion of large-angle oblique incidence laser shock peening, the existing technology uses energy compensation to ensure the strengthening effect, that is, by calculating the power density attenuation change caused by spot distortion, the size of the input energy is changed to ensure that the power density acting on the metal surface is consistent, thereby realizing the consistency of the strengthening effect. This method requires a large amount of redundant laser energy of the device, and for laser shock peening of aircraft structures, in order to improve processing efficiency, a large energy and large spot method is generally used, and the amount of redundant laser energy of the device is small, making it difficult to achieve effective compensation. In addition, existing research shows that under the same laser power density, the size and shape of the spot will affect the distribution of the residual stress field, and only by energy compensation can the laser power density be consistent under different oblique incidence conditions, which will not be able to control the uniformity of the residual stress field. SUMMARY

[0005] In view of the above prior art problems, the present application provides a spot dynamic correction device, system and method for oblique incidence laser shock peening.

[0006] To achieve the above object and other objects, the technical scheme adopted by the present application is as follows.

[0007] Optionally, a spot dynamic correction device for oblique incidence laser shock peening is provided, which comprises:

[0008] a base;

[0009] a beam shaping assembly arranged on one side of the base and configured to receive a light beam and generate a circular parallel light beam;

[0010] a beam correction assembly mounted on the base and configured to compress the circular parallel light beam into an elliptical parallel light beam, the beam correction assembly comprising a plano-convex cylindrical lens unit and a plano-concave cylindrical lens unit arranged in sequence, the plano-convex cylindrical lens unit being arranged on an outgoing light side of the beam shaping assembly, and the plano-concave cylindrical lens unit being arranged on an outgoing light side of the plano-convex cylindrical lens unit; and

[0011] a beam focusing assembly arranged on an outgoing light side of the plano-concave cylindrical lens unit.

[0012] Optionally, the plano-convex cylindrical lens unit comprises:

[0013] a first support mounted on one end of the base close to the beam shaping assembly;

[0014] a plano-convex cylindrical lens movably mounted on the first support, a convex surface of the plano-convex cylindrical lens facing the outgoing light side of the beam shaping assembly, and configured to continuously compress the circular parallel light beam into an elliptical light beam.

[0015] Optionally, the plano-convex cylindrical lens unit further comprises:

[0016] a first driving part mounted on the first support, an output end of the first driving part being connected to the plano-convex cylindrical lens, and configured to control the plano-convex cylindrical lens to rotate around a direction perpendicular to an axis of the plano-convex cylindrical lens.

[0017] Optionally, the plano-concave cylindrical lens unit comprises:

[0018] a second support mounted on one end of the base close to the beam focusing assembly;

[0019] A flat-concave cylindrical lens is installed on the second support, a flat surface of the flat-concave cylindrical lens faces the light-emitting side of the flat-convex cylindrical lens unit, and is used to generate the elliptical parallel light beam.

[0020] Optionally, the flat-concave cylindrical lens unit further comprises:

[0021] A second driving part is installed on the second support, an output end of the second driving part is connected to the flat-concave cylindrical lens, and is used to control the flat-concave cylindrical lens to rotate around a direction perpendicular to an axis of the flat-concave cylindrical lens.

[0022] Optionally, the flat-concave cylindrical lens unit further comprises:

[0023] A sliding part comprises a sliding rail and a sliding platform, the sliding rail is arranged on the base near one end of the light beam focusing assembly, and the sliding platform is in sliding connection with the sliding rail.

[0024] The second support is installed on the sliding platform, and is used to slide with the sliding platform on the sliding rail to approach or move away from the flat-convex cylindrical lens unit.

[0025] Optionally, the flat-concave cylindrical lens unit further comprises:

[0026] A third driving part is installed on the base, an output end of the third driving part is connected to the sliding platform, and is used to control the sliding platform to slide on the sliding rail to move away from or approach the flat-convex cylindrical lens unit.

[0027] Optionally, a light spot dynamic shaping system for the light spot dynamic shaping device for oblique incidence laser shock peening is provided, and the light spot dynamic shaping system comprises:

[0028] A light spot dynamic shaping device is used to compress a light beam into an elliptical parallel light beam through a flat-convex cylindrical lens unit and a flat-concave cylindrical lens unit.

[0029] A control module is in electrical connection with the light spot dynamic shaping device, is used to regulate an angle of a lens in the flat-convex cylindrical lens unit and the flat-concave cylindrical lens unit, to control a shaping direction of the elliptical parallel light beam, and is used to regulate a distance between the flat-convex cylindrical lens unit and the flat-concave cylindrical lens unit, to control a shaping degree of the elliptical parallel light beam.

[0030] Optionally, a method for light spot dynamic shaping by using the light spot dynamic shaping device for oblique incidence laser shock peening is provided, and the method comprises:

[0031] Obtaining a structural feature of a part to be strengthened and a preset angle of light beam oblique incidence;

[0032] The structure features and the preset angle of the oblique incidence of the light beam are used for processing path calculation to obtain a preset strengthening processing path;

[0033] According to the preset strengthening processing path, the light beam shaping assembly is adjusted to compress the circular parallel light beam generated by the light beam shaping assembly into an elliptical parallel light beam.

[0034] The light beam shaping assembly comprises a plano-convex cylindrical lens unit and a plano-concave cylindrical lens unit arranged in sequence, the plano-convex cylindrical lens unit is arranged on the light emitting side of the light beam shaping assembly, and the plano-concave cylindrical lens unit is arranged on the light emitting side of the plano-convex cylindrical lens unit.

[0035] Optionally, according to the preset strengthening processing path, the light beam shaping assembly is adjusted, comprising:

[0036] According to the preset strengthening processing path, the lenses in the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit are adjusted to rotate by the same angle, and the distance between the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit is adjusted within a preset distance threshold range.

[0037] As described above, the present application provides a spot dynamic shaping device for oblique incidence laser shock peening, the light beam shaping assembly receives the circular laser beam emitted by the light source, and generates a circular parallel light beam after shaping and adjustment; the circular parallel light beam is continuously compressed into an elliptical light beam after passing through the plano-convex cylindrical lens unit, and the elliptical light beam generates an elliptical parallel light beam after passing through the plano-concave cylindrical lens unit; the light beam focusing assembly receives the elliptical parallel light beam and focuses to generate an elliptical parallel light beam with high power density. After the elliptical parallel light beam with high power density is elongated on the intersection line of the light beam incident surface and the surface of the part, the impact spot trace is circular.

[0038] The method for spot dynamic shaping provided by the present application analyzes the spot distortion degree and distortion direction according to the structure features of the region to be strengthened and the preset angle of the oblique incidence of the light beam, calculates the angle and distance of the corresponding plano-convex cylindrical lens and plano-concave cylindrical lens of each impact spot in the preset strengthening processing path, to generate an elliptical parallel light beam with high power density transmitted along the preset angle, which forms a circular spot when irradiating on the part surface in the region to be strengthened; meanwhile, the shaping direction and degree of each impact spot can be adjusted in real time during the laser shock peening process, to ensure that the impact spot trace is always circular, and the light beam energy does not attenuate, thereby realizing the consistency of the strengthening processing effect.

[0039] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0040] The accompanying drawings, which are incorporated herein and constitute part of the specification, illustrate embodiments consistent with the application and, together with the description, further serve to explain the principles of the application. It is to be understood that the drawings are only schematic, and that they do not purport to be to scale with respect to one another. The embodiments presented herein are by way of example only, and various modifications can be made without departing from the spirit of the application.

[0041] Figure 1 A schematic diagram of a circular beam forming a spot on a part surface during oblique incidence laser shock peening is provided for an exemplary embodiment of the application.

[0042] Figure 2 A structural schematic diagram of a spot dynamic correction device for oblique incidence laser shock peening is provided for an exemplary embodiment of the application.

[0043] Figure 3 A structural schematic diagram of a spot dynamic correction system for oblique incidence laser shock peening is provided for an exemplary embodiment of the application.

[0044] Figure 4 A flowchart of a spot dynamic correction method for oblique incidence laser shock peening is provided for an exemplary embodiment of the application.

[0045] Figure 5 An effect schematic diagram of a spot dynamic correction method for oblique incidence laser shock peening is provided for an exemplary embodiment of the application.

[0046] In the figure, 1 is an incident light beam of a light source, 2 is a light beam shaping assembly, 3 is a circular parallel light beam, 4 is a plano-convex cylindrical lens, 5 is a convergent elliptical light beam, 6 is a plano-concave cylindrical lens, 7 is an elliptical parallel light beam, 8 is a light beam focusing assembly, 9 is a laser shock peening light beam, 10 is a region to be strengthened, 11 is a first support, 12 is a first driving part, 13 is a base, 14 is a sliding platform, 15 is a second support, 16 is a second driving part, 17 is a third driving part, 18 is a control bus, and 19 is a control terminal. DETAILED DESCRIPTION

[0047] The present application is herein described, by way of example only, with reference to certain embodiments thereof. It is to be understood that the embodiments and features which are disclosed herein can be combined with each other, unless specifically stated otherwise. It is also to be understood that the specific examples herein are meant to be exemplary only and that the scope of the application is not intended to be limited to the specific examples presented herein.

[0048] It is to be noted that the drawings provided in the following embodiments merely illustrate the basic concept of the present application in a schematic way, and only the components related to the present application are shown in the drawings, rather than being drawn according to the number, shape and size of the components in actual implementation, and the shape, number and ratio of each component in actual implementation can be arbitrarily changed, and the component layout pattern can also be more complex.

[0049] In the following description, numerous specific details are discussed in order to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to one of ordinary skill in the art that the embodiments of the present application can be practiced without these specific details. In other instances, well-known structures and devices are not described in detail in order to avoid obscuring the embodiments of the present application.

[0050] In the present application, "a plurality of" means two or more. The association relationship of "and / or" describes the associated objects, which means that there can be three relationships, for example, A and / or B can represent the following three cases: A exists alone, A and B exist together, and B exists alone. The character " / " generally represents an "or" relationship between the front and rear associated objects.

[0051] First of all, it needs to be pointed out that beam shaping is to convert a Gaussian (TEM00) incident laser beam into a circular, rectangular, square, straight line or other custom shape. When actually performing beam shaping operation, there are many beam shapers to choose from. The spot generated by the beam shaper is often used for laser processing, which can prevent overexposure or underexposure in a specific area. Typical applications of beam shapers include cutting, ablation, drilling, scribing, annealing, medicine and aesthetics, microscopy and science, and optical cell counting.

[0052] A plano-convex cylindrical lens is a lens with one flat surface and one convex surface, also known as a positive cylindrical lens. A plano-concave cylindrical lens is a lens with one flat surface and one concave surface, also known as a negative cylindrical lens. A positive cylindrical lens is equivalent to a section cut from a cylinder; a negative cylindrical lens is equivalent to a section taken from the outer model of a cylinder. There is no curvature in the direction of the cylinder axis, and the curvature is zero. In the direction perpendicular to the center line of the cylinder, there is the maximum curvature. Since the cylindrical lens has zero curvature in the direction parallel to the axis, there is no bending, so the light passing through the cylindrical lens will not be bent in this direction; the cylindrical lens has the maximum curvature in the direction perpendicular to the axis, so the light passing through the cylindrical lens will be bent the most in this direction. Parallel light beams converge (or diverge) to a focal point after passing through the cylindrical lens, and the focal point forms a straight line called the focal line, which is parallel to the axis.

[0053] The technical scheme of the embodiment of the present application relates to the technical field of laser shock peening, and is specifically explained as follows:

[0054] Figure 1 A schematic diagram of a circular light spot formed on a part surface during oblique incidence laser shock peening is provided for the exemplary embodiment of the present application.

[0055] Referring to Figure 1 When the circular laser beam with a radius of R is obliquely irradiated on the part surface, the included angle between the laser beam direction and the normal line of the peening surface is θ, at this time, the laser shock spot acting on the peening surface of the part is elongated in the intersection direction of the laser incidence surface and the peening surface of the part, and an elliptical shock spot is formed, at this time, the long axis of the elliptical spot is 2R / cosθ, and the short axis is R. When θ is greater than 15°, the spot distortion is serious, and the effect of laser shock peening is reduced. Therefore, the spot dynamic correction and the reduction of the circularity are important factors to ensure the peening effect, and the dynamic adjustment method during the peening process is also an essential function of the laser shock peening equipment.

[0056] In the embodiment, a spot dynamic correction device for oblique incidence laser shock peening is first provided, as shown in Figure 2 , and Figure 2 A structural schematic diagram of the spot dynamic correction device for oblique incidence laser shock peening is provided for the exemplary embodiment of the present application, and the spot dynamic correction device comprises a base 13, a beam shaping assembly 2, a beam correction assembly, and a beam focusing assembly 8. The beam shaping assembly 2 is arranged on one side of the base 13 and is used to generate a circular parallel light beam 3. The beam correction assembly is installed on the base 13 and is used to compress the circular parallel light beam 3 into an elliptical parallel light beam 7. The beam correction assembly comprises a plano-convex cylindrical lens unit and a plano-concave cylindrical lens unit arranged in sequence. The plano-convex cylindrical lens unit is arranged on the light exit side of the beam shaping assembly 2, and the plano-concave cylindrical lens unit is arranged on the light exit side of the plano-convex cylindrical lens unit. The beam focusing assembly 8 is arranged on the light exit side of the plano-concave cylindrical lens unit.

[0057] For example, in the embodiment of the present application, the beam shaping assembly 2 is a shaping lens group. After the circular laser beam emitted by the light source passes through the shaping lens group, the divergent laser beam is shaped into a parallel laser beam to obtain a circular parallel light beam. The beam focusing assembly 8 is a focusing lens group. After the elliptical parallel light beam 7 passes through the focusing lens group, a high-power-density laser beam is generated. When the high-power-density laser beam irradiates on the part surface, the shock peening can be performed.

[0058] The spot dynamic shaping device for oblique incidence laser shock peening provided by the embodiment of the application comprises a light beam shaping assembly 2, a first support 11, a plano-convex cylindrical lens 4, a first driving part 12, a base 13, a plano-concave cylindrical lens unit, and a light beam focusing assembly 8.

[0059] In an embodiment of the application, the plano-convex cylindrical lens unit comprises the first support 11 installed on the base 13 near one end of the light beam shaping assembly 2, and the plano-convex cylindrical lens 4 movably installed on the first support 11, wherein the convex surface of the plano-convex cylindrical lens 4 faces the light exit side of the light beam shaping assembly 2, and is used for compressing the circular parallel light beam 3 into the convergent elliptical light beam 5. In the embodiment, after the circular parallel light beam 3 passes through the plano-convex cylindrical lens 4, the circular parallel light beam 3 is compressed into the convergent elliptical light beam 5 in the direction perpendicular to the axis of the cylindrical lens due to the light transmission principle of the plano-convex cylindrical lens 4, and the compression degree is higher at a farther distance.

[0060] In an embodiment of the application, the plano-convex cylindrical lens unit further comprises the first driving part 12 installed on the first support 11, wherein the output end of the first driving part 12 is connected to the plano-convex cylindrical lens 4, and the first driving part 12 is used for controlling the plano-convex cylindrical lens 4 to rotate around the direction perpendicular to the axis of the plano-convex cylindrical lens 4. In the embodiment, the length of the major axis of the generated elliptical light beam can be controlled by adjusting the angle of the plano-convex cylindrical lens 4 towards the light beam shaping assembly 2. In the embodiment, the first driving part 12 is an adjusting motor, and the output end of the adjusting motor is connected to the transverse shaft of the plano-convex cylindrical lens 4 through a transmission mechanism. When the adjusting motor rotates, the plano-convex cylindrical lens 4 can be driven to rotate around the direction perpendicular to the axis of the plano-convex cylindrical lens 4 by a certain angle, so as to change the length of the major axis of the elliptical cross section of the convergent elliptical light beam 5.

[0061] In an embodiment of the present application, the plano-concave cylindrical lens unit comprises: a second support 15, which is installed on the base 13 near one end of the light beam focusing assembly 8; a plano-concave cylindrical lens 6, which is installed on the second support 15, and the plane of the plano-concave cylindrical lens 6 faces the light exit side of the plano-convex cylindrical lens unit, for generating an elliptical parallel light beam 7. In this embodiment, the converging elliptical light beam 5 passes through the plano-concave cylindrical lens 6, and based on the light transmission principle of the plano-concave cylindrical lens 6, the converging light beam is diverged into a parallel light beam, generating an elliptical parallel light beam 7.

[0062] In an embodiment of the present application, the plano-concave cylindrical lens unit further comprises: a second driving part 16, which is installed on the second support 15, and the output end of the second driving part 16 is connected to the plano-concave cylindrical lens 6, for controlling the rotation of the plano-concave cylindrical lens 6 around the direction perpendicular to its own axis. In this embodiment, the second driving part 16 is an adjusting motor, and the output end of the adjusting motor is connected to the plano-concave cylindrical lens 6 through a transmission mechanism. When the adjusting motor rotates, it can drive the plano-concave cylindrical lens 6 to rotate around the direction perpendicular to its own axis by a certain angle, thereby adjusting the length of the major axis of the elliptical cross section of the elliptical parallel light beam 7.

[0063] In an embodiment of the present application, the plano-concave cylindrical lens unit further comprises a sliding part and a third driving part 17. The sliding part comprises a sliding rail and a sliding platform 14, the sliding rail is arranged on the base 13 near one end of the light beam focusing assembly 8, and the sliding platform 14 is in sliding connection with the sliding rail. The second support 15 is installed on the sliding platform 14, for reciprocating movement on the sliding rail with the sliding platform 14 to approach or move away from the plano-convex cylindrical lens unit; the plano-concave cylindrical lens 6 is installed on the second support 15, and the plane of the plano-concave cylindrical lens 6 faces the light exit side of the plano-convex cylindrical lens unit, for generating an elliptical parallel light beam 7; the second driving part 16 is installed on the second support 15, and the output end of the second driving part 16 is connected to the plano-concave cylindrical lens 6, for controlling the rotation of the plano-concave cylindrical lens 6 around the direction perpendicular to its own axis; and the third driving part 17 is installed on the base 13, and the output end of the third driving part 17 is connected to the sliding platform 14, for controlling the reciprocating movement of the sliding platform 14 on the sliding rail to approach or move away from the plano-convex cylindrical lens unit. In this embodiment, the third driving part 17 is an adjusting motor, and the output end of the adjusting motor is connected to the sliding platform 14 through a transmission assembly. When the adjusting motor rotates, it will control the reciprocating movement of the sliding platform 14 on the sliding rail to approach or move away from the plano-convex cylindrical lens unit, and adjust the distance between the plano-convex cylindrical lens 4 and the plano-concave cylindrical lens within a predetermined distance threshold range, to control the degree of dynamic correction of the light spot. When adjusting the distance between the two lenses, the lens spacing must be less than the focal length of the plano-convex cylindrical lens.

[0064] The spot dynamic correction device for oblique incidence laser shock peening provided in the application sequentially arranges a plano-convex cylindrical lens 4 and a plano-concave cylindrical lens 6 in the light beam emitting direction, and the circular light beam forms an elliptical parallel light beam 7 irradiated at a preset angle after passing through the two lenses, so that the impact spot of the part to be strengthened region 10 is circular; the rotation angle of the lenses is controlled through two adjusting motors to control the length of the major axis of the elliptical cross section of the elliptical light beam 7; the distance between the two lenses is adjusted within a preset distance threshold range to control the dynamic correction degree of the light spot, that is, to control the size of the minor axis of the elliptical parallel light beam, so that the traces of the impact spots are always circular during the oblique incidence processing of different regions, and the strengthening effect is guaranteed.

[0065] In an embodiment of the application, a spot dynamic correction system for oblique incidence laser shock peening is provided, which is implemented by using the above-mentioned spot dynamic correction device. Referring to Figure 3 , Figure 3 A structure diagram of a spot dynamic correction system for oblique incidence laser shock peening provided for an exemplary embodiment of the application. The system comprises: a spot dynamic correction device for compressing the light beam emitted by the light source into an elliptical parallel light beam 7 through a plano-convex cylindrical lens unit and a plano-concave cylindrical lens unit; a control module electrically connected with the spot dynamic correction device, for adjusting the angle of the lenses in the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit to control the correction direction of the elliptical parallel light beam 7, and for adjusting the distance between the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit to control the correction degree of the elliptical parallel light beam 7. In this embodiment, the control module comprises a control terminal 19 and a control bus 18; the specific structure of the spot dynamic correction device has been described in the above description, and will not be repeated here. The control terminal 19 acquires the structural features of the part to be strengthened region 10 and the preset angle of the light beam oblique incidence, calculates the strengthening processing path based on the structural features and the preset angle of the light beam oblique incidence, obtains the preset strengthening processing path, calculates the angle at which the lenses need to be rotated and the distance that needs to be adjusted based on the preset strengthening processing path, and generates a control instruction. The control instruction is transmitted to the spot dynamic correction device through the control bus 18 to control the rotation of the adjusting motor, so as to control the rotation angle and the distance of the lenses.

[0066] In an embodiment of the application, a spot dynamic correction method for oblique incidence laser shock peening is provided, which uses the above-mentioned spot dynamic correction device for spot dynamic correction. Referring to Figure 4 , Figure 4 A flowchart of a spot dynamic correction method for oblique incidence laser shock peening provided for an exemplary embodiment of the application, which comprises the following steps:

[0067] S410, acquiring the structural features of the part to be strengthened region and the preset angle of the light beam oblique incidence;

[0068] S420, a preset strengthening machining path calculation is performed on the structural features and the preset angle of oblique incidence of the light beam, to obtain a preset strengthening machining path;

[0069] S430, according to the preset strengthening machining path, the light beam shaping assembly is adjusted to compress the circular parallel light beam generated by the light beam shaping assembly into an elliptical parallel light beam.

[0070] In the embodiment, the control terminal 19 arranges the impact spots according to the structural features of the part to be strengthened and the preset angle of oblique incidence of the light beam, sets the preset strengthening machining path, and sets the angle and the distance between the flat convex cylindrical lens 4 and the flat concave cylindrical lens 6 corresponding to each impact spot; the light beam 1 emitted from the laser is adjusted into a circular parallel laser beam by the light beam shaping assembly 2; the circular parallel laser beam is changed into an elliptical parallel light beam 7 compressed in the direction perpendicular to the cylindrical mirror axis after passing through the flat convex cylindrical lens 4 and the flat concave cylindrical lens 6, and the light intensity does not change; the elliptical parallel light beam 7 generates an elliptical parallel laser beam with high power density after passing through the light beam focusing assembly 8, and irradiates on the surface of the part at a certain angle according to the set spot size; the impact spot trace is circular after the elliptical parallel laser beam with high power density is elongated in the intersection direction of the laser incidence surface and the part strengthening surface; after the current impact spot is completed and before the next impact spot starts, the control terminal 19 adjusts the angle of the flat convex cylindrical lens 4 and the flat concave cylindrical lens 6 and the distance between the two to adjust the shaping direction and the shaping degree of the light spot, that is, to adjust the length of the major axis and the minor axis of the elliptical cross section of the elliptical light beam. In this way, the trace of the impact spot during oblique incidence machining is always circular, and the strengthening effect is guaranteed.

[0071] Referring to Figure 5 , Figure 5 An effect schematic diagram of a spot dynamic shaping method for oblique incidence laser impact strengthening provided for an exemplary embodiment of the present application. The angle between the laser impact strengthening light beam 9 and the normal of the surface of the part is θ, the cross-sectional area of the circular light beam is πR 2 After passing through the flat convex cylindrical lens and the flat concave cylindrical lens, an elliptical parallel light beam with a cross-sectional area of πR 2 cosθ is generated, the elliptical parallel light beam is elongated in the intersection direction of the laser incidence surface and the part strengthening surface, and a circular spot with an area of πR 2 is formed.

[0072] In summary, the application provides a spot dynamic correction device, system and method for oblique incidence laser shock peening, which can change the circular light beam incident by the light source into an elliptical parallel light beam through the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit, and can generate a circular spot when the elliptical parallel light beam irradiates the area to be strengthened of the part at a large angle, without affecting the strengthening effect; in addition, by adjusting the angle and spacing of the lens, a uniform residual compressive stress field can be formed for each spot. Therefore, the application effectively overcomes the various shortcomings in the prior art and has high industrial utilization value.

[0073] The above embodiments only exemplarily illustrate the principles and effects of the application, and are not used to limit the application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the application should be covered by the claims of the application.

Claims

1. A spot dynamic correction device for oblique incidence laser shock peening, characterized in that, include: Base; A beam shaping assembly, disposed on one side of the base, is used to receive the beam and generate a circular parallel beam; A beam shaping assembly, mounted on the base, is used to compress the circular parallel beam into an elliptical parallel beam. The beam shaping assembly includes a plano-convex cylindrical lens unit and a plano-concave cylindrical lens unit arranged sequentially. The plano-convex cylindrical lens unit is located on the light-emitting side of the beam shaping assembly, and the plano-concave cylindrical lens unit is located on the light-emitting side of the plano-convex cylindrical lens unit. The convex surface of the plano-convex cylindrical lens in the plano-convex cylindrical lens unit faces the light-emitting side of the beam shaping assembly, and the flat surface of the plano-concave cylindrical lens in the plano-concave cylindrical lens unit faces the light-emitting side of the plano-convex cylindrical lens unit. A beam focusing assembly is disposed on the light-emitting side of the plano-concave cylindrical lens unit to irradiate the focused laser shock enhancement beam onto the area to be enhanced of the part, forming a circular light spot. The dynamic correction degree of the light spot is controlled by adjusting the distance between the plano-convex cylindrical lens and the plano-concave cylindrical lens within a preset distance threshold range. The plano-convex cylindrical lens unit includes: The first bracket is installed on the base at one end near the beam shaping component; A plano-convex cylindrical lens is movably mounted on the first bracket. The plano-convex cylindrical lens is used to continuously compress the circular parallel beam into an elliptical beam. The plano-convex cylindrical lens unit also includes: A first drive unit is mounted on the first bracket. The output end of the first drive unit is connected to the plano-convex cylindrical lens and is used to control the plano-convex cylindrical lens to rotate about a direction perpendicular to its own axis.

2. The oblique incidence laser shock peening spot dynamic straightening device according to claim 1, characterized in that, The plano-concave cylindrical lens unit includes: The second bracket is installed on the base at one end near the beam focusing assembly; A plano-concave cylindrical lens is mounted on the second bracket, and the plano-concave cylindrical lens is used to generate the elliptical parallel beam.

3. The oblique incidence laser shock peening spot dynamic reshaping apparatus of claim 2, wherein, The plano-concave cylindrical lens unit further includes: The second drive unit is mounted on the second bracket. The output end of the second drive unit is connected to the plano-concave cylindrical lens and is used to control the plano-concave cylindrical lens to rotate about a direction perpendicular to its own axis.

4. The oblique incidence laser shock peening spot dynamic reshaping apparatus of claim 3, wherein, The plano-concave cylindrical lens unit further includes: The sliding part includes a slide rail and a sliding platform. The slide rail is disposed on the base near one end of the beam focusing component, and the sliding platform is slidably connected to the slide rail. The second bracket is mounted on the sliding platform and is used to slide along the slide rail to move closer to or further away from the plano-convex cylindrical lens unit.

5. The oblique incidence laser shock peening spot dynamic reshaping apparatus of claim 4, wherein, The plano-concave cylindrical lens unit further includes: The third drive unit is mounted on the base, and its output end is connected to the sliding platform to control the sliding platform to slide on the slide rail to move away from or closer to the plano-convex cylindrical lens unit.

6. A spot dynamic correction system using the spot dynamic correction device for oblique incidence laser shock peening according to any one of claims 1 to 5, characterized in that, The light spot dynamic correction system includes: A dynamic beam correction device is used to compress a light beam into an elliptical parallel beam by passing it through a plano-convex cylindrical lens unit and a plano-concave cylindrical lens unit. A control module is electrically connected with the light spot dynamic orthotic device, and is configured to control the angle of the lenses in the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit to control the orthotic direction of the elliptical parallel light beam, and to control the distance between the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit to control the orthotic degree of the elliptical parallel light beam.

7. A method for performing dynamic beam shaping using the dynamic beam shaping device for oblique incidence laser peening according to any one of claims 1 to 5, characterized in that, Comprise: Obtaining the structural features of the part to be strengthened and the preset angle of oblique incidence of the light beam; The structure characteristics and the preset angle of oblique incidence of the light beam are calculated to obtain the preset strengthening machining path; According to the preset strengthening machining path, adjusting the light beam orthotic assembly to compress the circular parallel light beam generated by the light beam shaping assembly into an elliptical parallel light beam; The light beam orthotic assembly comprises a plano-convex cylindrical lens unit and a plano-concave cylindrical lens unit arranged in sequence, the plano-convex cylindrical lens unit is arranged on the light emitting side of the light beam shaping assembly, and the plano-concave cylindrical lens unit is arranged on the light emitting side of the plano-convex cylindrical lens unit.

8. The method of dynamic correction of the light spot according to claim 7, characterized in that, According to the preset strengthening machining path, adjusting the light beam orthotic assembly, comprising: According to the preset strengthening machining path, adjusting the lenses in the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit to rotate by the same angle, and adjusting the distance between the plano-convex cylindrical lens unit and the plano-concave cylindrical lens unit within a preset distance threshold range.

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