Method for establishing point-ring laser welding heat source model, system and medium

Abstract

The present invention relates to the technical field of laser welding. Disclosed are a method for establishing a point-ring laser welding heat source model, a system and a medium. A point-ring laser is composed of point light of a central laser body heat source and ring light of an annular laser surface heat source, the point light is used for achieving a weld seam having a high depth-to-width ratio for a welded material, and the ring light is used for achieving auxiliary heating and slow cooling for the welded material. According to the method for establishing a point-ring laser welding heat source model provided in the present invention, the laser power ratio of the point light to the ring light in the model can be regulated and controlled according to any proportion, the defocusing amounts of the point light and the ring light can be separately controlled, and spot parameters such as point light spot diameter and ring light spot diameter can be used for effectively expressing heat flux density distribution. The method for establishing a heat source model provides a powerful reference basis for accurately simulating a temperature field, a stress field and a deformation field of point-ring laser welding. On the basis of regulation and control of a welding path, the present invention can be widely applied to the field of finite element simulation of point-ring laser linear welding and weaving welding.

Description

Method, system and medium for establishing heat source model of spot ring laser welding Technical Field

[0001] The present invention relates to the field of laser welding, specifically, to the field of laser welding finite element simulation, and in particular to a method, system and medium for establishing a point ring laser welding heat source model. Background Art

[0002] Laser welding technology is widely used in fields such as new energy, aerospace, and electronic equipment. It is an advanced welding technology with advantages such as high precision, high efficiency, and a high degree of automation. With the development of automation technology, swing welding technology has gradually been introduced into the laser welding field. By controlling the swinging motion of the laser beam through a swinging head and a galvanometer lens, this automated swing laser welding can improve the stability, consistency, and accuracy of welding and reduce human error. Swing laser welding effectively solves the problem of excessive assembly precision requirements in traditional narrow-gap laser welding. In recent years, laser systems have been continuously upgraded and improved, and ring-core adjustable laser welding technology has been introduced to the laser welding market. The most representative is the ring-core adjustable laser produced by TRUMPF. Ring-core adjustable laser, also known as point ring light, is a new laser beam mode. Conventional lasers only output a single point light source through their optical fibers, while the point ring light output by a ring-core adjustable laser adds a ring light source to the conventional point light source, forming a point ring light beam mode. During the welding process, the front ring light in the welding direction preheats the metal material, while the rear ring light in the welding direction slows down the cooling of the metal material. Reports have shown that compared to conventional laser welding, spot ring laser welding produces significantly less spatter. However, the welding characteristics, spot ring energy ratio, process parameter matching, and spatter suppression mechanism of spot ring light remain unclear. The energy distribution of spot ring light is different from that of conventional lasers. There is a correlation between welding spatter and the dynamic behavior of the keyhole during welding. When analyzing this correlation from the perspective of energy distribution, finite element simulation can be used to simulate the flow behavior and heat transfer characteristics of the molten pool of metal materials during welding. Establishing a welding heat source model is the first step in conducting finite element simulation of laser welding. It provides the energy distribution form of the welding heat source. Currently, there is no good model to characterize the spot ring laser welding heat source, especially the spot ring laser swing welding heat source. Therefore, it is necessary to provide a spot ring laser welding heat source model. Summary of the Invention

[0003] 1. Technical problems to be solved

[0004] The purpose of the present invention is to solve the problem that it is difficult to establish a heat source model for point-ring laser welding of a ring-core tunable laser, and to provide a method, system and medium for establishing a heat source model for point-ring laser welding.

[0005] 2. Technical solution

[0006] The purpose of the present invention is achieved through the following technical solutions.

[0007] A first aspect of the present invention provides a method for establishing a heat source model for spot ring laser welding, comprising the following steps:

[0008] Establish a point-ring laser welding heat source model: The point-ring laser consists of the point light of the central laser body heat source and the ring light of the annular laser surface heat source. The control equations of the point-ring laser welding heat source are shown in formulas (1) and (2):

[0009] In formulas (1) and (2), q Total (x, y, z) represents the total heat flux density function of the spot ring laser welding heat source, (x, y, z) represents the coordinates of the global coordinate system, α represents the laser power distribution coefficient, which refers to the power ratio of the point light in the spot ring laser. The laser power distribution coefficient α has a value range of [0, 1], where α = 0 represents the laser heat source as a ring light, 0 < α < 1 represents the laser heat source as a point ring light, and α = 1.0 represents the laser heat source as a point light. Q represents the total input laser power, β represents the heat flux concentration coefficient of the central laser, γ represents the heat flux concentration coefficient of the ring laser, H represents the effective heating depth of the body heat source, and there is a heat source heating effect within the heat source depth in the [-H, 0] interval. The spot parameters include r v 、r s , r1 and r2, r v represents the effective heating radius of the central laser body heat source, the subscript v represents the body heat source; r s represents the location where the heat flux density of the annular laser surface heat source is the largest, and the subscript s represents the surface heat source; the effective heating range of the annular laser surface heat source is [r 1, r2].

[0010] Establishing a welding path equation: the welding path equation is one or more of a linear welding control equation, a circular swing welding control equation, a sinusoidal swing welding control equation, and a linear swing welding control equation;

[0011] Obtain the movement equation of the point-ring laser welding heat source model: Select the required welding path form, substitute the welding control equation corresponding to the welding path form into the control equation of the welding heat source (1), and obtain the movement equation of the point-ring laser welding heat source model.

[0012] In some embodiments, the language code program of the point ring laser welding heat source model in formulas (1) and (2) is written by language compilation software to generate welding heat source data and pictures for later optimization. The heat source heat flux density peak value will be generated in the picture, and the peak value range is 10 6 -10 7 W / cm 2 .

[0013] Specifically, in the step of establishing the welding path equation:

[0014] The linear welding control equation is established as shown in formula (3):

[0015] In formula (3), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, and t represents the welding time; the welding trajectory is a straight line.

[0016] The circular swing welding control equation is established as shown in formula (4):

[0017] In formula (4), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, t represents the welding time, r represents the radius of the swing circle, and T represents the swing period of the swing circle; the welding trajectory is a spiral line.

[0018] The sinusoidal oscillation welding control equation is established as shown in formula (5):

[0019] In formula (5), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, t represents the welding time, r represents the amplitude of the sinusoidal oscillation, and T represents the oscillation period of the sinusoidal oscillation; the welding trajectory is a sinusoidal line.

[0020] The linear swing welding control equations are established as shown in equations (6)-(8):

[0021] In formulas (6)-(8), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, t represents the welding time, and r represents the swing amplitude of the linear swing. In one swing cycle The reciprocating speeds inside are v1 and v2 respectively. When v1 = -v2, the welding trajectory is an isosceles triangle waveform.

[0022] The global coordinate system of formulas (3) to (8) should match the coordinate system of the three-dimensional finite element mesh model. That is, the coordinates (x0, y0, z0) in the movement equation of the spot ring laser welding heat source model are the starting welding positions of the three-dimensional finite element mesh model, and the relative displacement between z0 and the workpiece surface in formulas (3)-(6) represents the defocus amount.

[0023] Furthermore, the desired welding path form is selected, and formulas (3), (4), (5) or (6)-(8) are selected and substituted into formula (1) to obtain the movement equation of the spot ring laser welding heat source model.

[0024] In some embodiments, a language code program of a moving heat source model of spot ring laser welding is written based on language compilation software to facilitate the subsequent simulation software to call subroutines.

[0025] Furthermore, the method for establishing the heat source model of the spot ring laser welding requires establishing a three-dimensional solid thermal conduction partial differential equation with a heat source and a transient temperature field and solving it in the finite element calculation software to perform thermal-mechanical coupling operations. The three-dimensional solid thermal conduction partial differential equation with a heat source and a transient temperature field is shown in formula (9):

[0026] In formula (9), T represents the transient temperature of the material, t represents the welding and cooling time, k represents the thermal conductivity of the material, ρ represents the material density, c p represents the specific heat of the material, q Total (x, y, z) represents the total heat flux density function of the spot ring laser welding heat source shown in formula (1), and (x, y, z) are the coordinates of the global coordinate system.

[0027] The method for establishing the heat source model of the spot ring laser welding in the present invention is applicable to weldable thin sheet metal materials, including but not limited to common metal materials such as aluminum alloy, stainless steel, titanium alloy, and copper alloy.

[0028] A second aspect of the present invention provides a spot ring laser welding system, comprising a spot ring laser, a spot ring laser fiber, a welding head, and a computing unit, wherein:

[0029] The dot ring laser is used to generate dot ring laser and emit the dot ring laser into the welding head through the dot ring laser optical fiber;

[0030] The welding head is provided with a motor and a control unit, and the control unit controls the motor to swing according to a set swing trajectory;

[0031] The computing unit includes a memory, a processor, and a communication bus; the communication bus realizes the connection and communication between the processor and the memory, and the processor executes one or more programs stored in the memory; the computing unit is used for finite element simulation calculation and process optimization, and feeds back the simulation results to the control unit for setting the swing trajectory and swing parameters to run the method for establishing the point ring laser welding heat source model of the first aspect of the present invention.

[0032] The third aspect of the present invention provides a computer-readable storage medium storing one or more programs, which can be executed by one or more processors to run the method for establishing the spot ring laser welding heat source model of the first aspect of the present invention.

[0033] 3. Beneficial effects

[0034] Compared with the existing technology, the advantages of the present invention are: the present invention establishes a brand-new point-ring laser welding heat source model, which can well simulate the energy distribution of the point-ring beam mode. By adjusting the laser power ratio parameters, the input power of the point light and the ring light can be regulated in any proportion. By changing the starting welding position (x0, y0, z0), the defocus amount of the point light and the ring light can be controlled separately. By combining the spot parameters such as the effective heating radius of the central laser body heat source and the effective heating range of the annular laser surface heat source, the heat flux density distribution of the point-ring laser can be effectively expressed. The method for establishing the heat source model provides a strong reference basis for accurately simulating the temperature field, stress field and deformation field of point-ring laser welding. Combined with the regulation of the welding path, the present invention can be widely used in the field of finite element simulation of point-ring laser linear welding and swing welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG1 is a schematic diagram of a heat source model for point ring laser welding according to the present invention;

[0036] FIG2 is a heat source model of ring light welding compiled based on MATLAB language according to an embodiment of the present invention;

[0037] FIG3 is a point ring light welding heat source model compiled based on MATLAB language according to an embodiment of the present invention;

[0038] FIG4 is a point light welding heat source model compiled based on MATLAB language according to an embodiment of the present invention;

[0039] FIG5 is a longitudinal cross-sectional morphology of the welding temperature field obtained by the ring light welding heat source model according to an embodiment of the present invention;

[0040] FIG6 is a longitudinal cross-sectional morphology of the welding temperature field obtained by the point ring light welding heat source model according to an embodiment of the present invention;

[0041] FIG7 is a longitudinal cross-sectional morphology of the welding temperature field obtained by the point light welding heat source model according to an embodiment of the present invention;

[0042] FIG8 is a cross-sectional morphology of the welding temperature field obtained by the ring-light welding heat source model according to an embodiment of the present invention;

[0043] FIG9 is a cross-sectional morphology of the welding temperature field obtained by the point ring light welding heat source model according to an embodiment of the present invention;

[0044] FIG10 is a cross-sectional morphology of the welding temperature field obtained by the point light welding heat source model according to an embodiment of the present invention;

[0045] FIG11 is a diagram of the weld surface morphology of the welding temperature field obtained by the circular oscillating point light and heat source model according to an embodiment of the present invention;

[0046] FIG12 is a diagram of the welding temperature field and weld surface morphology obtained by the sinusoidal oscillating point light heat source model according to an embodiment of the present invention;

[0047] FIG13 is a diagram showing the surface morphology of the weld seam obtained by the linear oscillating point light heat source model according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0049] Example 1

[0050] The technical solutions in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments proposed by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] The present invention provides a method for establishing a heat source model for spot ring laser welding, comprising the following steps:

[0052] Establish a heat source model for point-ring laser welding.

[0053] The point-ring laser consists of the point light of the central laser body heat source and the ring light of the annular laser surface heat source. The control equations of the point-ring laser welding heat source are shown in formulas (1) and (2):

[0054] In formulas (1) and (2), q Total (x, y, z) represents the total heat flux density function of the spot ring laser welding heat source, (x, y, z) represents the coordinates of the global coordinate system, α represents the laser power distribution coefficient, which refers to the power ratio of the point light in the spot ring laser, Q represents the total input laser power, β represents the heat flux concentration coefficient of the center laser, γ represents the heat flux concentration coefficient of the ring laser, H represents the effective heating depth of the body heat source, and there is a heat source heating effect within the heat source depth in the [-H, 0] interval. The spot parameters include r v 、r s , r1 and r2, r v represents the effective heating radius of the central laser body heat source, r s It represents the position where the heat flux density of the annular laser surface heat source is the largest. The effective heating range of the annular laser surface heat source is [r1, r2].

[0055] Based on the MATLAB language compiler software, a MATLAB language code program for the point ring laser welding heat source model described in formulas (1) and (2) was written to generate welding heat source data and images for later optimization. The same function can also be achieved using other languages, not limited to MATLAB.

[0056] Establish the welding path equation.

[0057] The linear welding control equation is established as shown in formula (3):

[0058] In formula (3), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, and t represents the welding time; the welding trajectory is a straight line.

[0059] The circular swing welding control equation is established as shown in formula (4):

[0060] In formula (4), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, t represents the welding time, r represents the radius of the swing circle, and T represents the swing period of the swing circle; the welding trajectory is a spiral line.

[0061] The sinusoidal oscillation welding control equation is established as shown in formula (5):

[0062] In formula (5), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, t represents the welding time, r represents the amplitude of the sinusoidal oscillation, and T represents the oscillation period of the sinusoidal oscillation; the welding trajectory is a sinusoidal line.

[0063] The linear swing welding control equations are established as shown in equations (6)-(8):

[0064] In formulas (6)-(8), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, t represents the welding time, and r represents the swing amplitude of the linear swing. In one swing cycle The reciprocating speeds inside are v1 and v2 respectively. When v1 = -v2, the welding trajectory is an isosceles triangle waveform.

[0065] Select the desired welding path form and substitute formula (3), (4), (5), or (6)-(8) into formula (1) to obtain the movement equation of the heat source model of the spot ring laser welding. In this embodiment, a FORTRAN language code program of the point ring laser welding movement heat source model is written based on FORTRAN language compiler software, which facilitates the subsequent simulation software to call the subroutine. Similarly, there is no restriction on the language in which the relevant program is written and called.

[0066] The global coordinate system of formula (3) to formula (8) should match the coordinate system of the three-dimensional finite element mesh model, that is, the coordinates (x0, y0, z0) in the movement equation of the spot ring laser welding heat source model are the starting welding position of the three-dimensional finite element mesh model, and the relative displacement of z0 in the formula (3)-(6) and the z-axis coordinate of the three-dimensional finite element mesh model represents the defocus amount.

[0067] The establishment method requires establishing a three-dimensional solid thermal conduction partial differential equation with a heat source and a transient temperature field and solving it in finite element calculation software to perform thermal-mechanical coupling operations. The three-dimensional solid thermal conduction partial differential equation with a heat source and a transient temperature field is shown in formula (9):

[0068] In formula (9), T represents the transient temperature of the material, t represents the welding and cooling time, k represents the thermal conductivity of the material, ρ represents the material density, c p represents the specific heat of the material, q Total (x, y, z) represents the total heat flux density function of the spot ring laser welding heat source shown in formula (1), and (x, y, z) are the coordinates of the global coordinate system.

[0069] The method for establishing a heat source model for spot-ring laser welding of the present invention is applicable to weldable thin-plate metal materials, including but not limited to common metal materials such as aluminum alloy, stainless steel, titanium alloy, and copper alloy.

[0070] This process is described in detail below with reference to a specific embodiment.

[0071] FIG1 is a schematic diagram of the heat source model of the point ring laser welding established by the present invention. According to FIG1 , formula (1) and formula (2), the variable parameters are set as follows: the effective heating radius r of the central laser body heat source v =0.3mm, the effective heating range of the annular laser surface heat source is r1 = 0.4mm and r2 = 0.8mm, and the maximum heat flux density position of the annular laser surface heat source is r s =0.6mm, total laser power Q=2000W;

[0072] Figures 2-4 are respectively ring-light, point-ring-light, and point-light welding heat source models compiled based on the MATLAB language according to an embodiment of the present invention. The laser power distribution coefficients α are 0, 0.6, and 1.0, respectively. α = 0 represents a ring-light laser heat source, α = 0.6 represents a point-ring laser heat source, and α = 1.0 represents a point-light laser heat source. Based on the MATLAB language compilation software, MATLAB language code programs for the point-ring laser welding heat source models described in formulas (1) and (2) were written, and the generated welding heat source images are shown in Figures 2-4.

[0073] To establish the welding path equation, we first select the linear welding control equation shown in formula (3). Based on the FORTRAN language compiler software, we compile the FORTRAN language code program of the point-ring laser welding moving heat source model, where the laser power distribution coefficient α is 0, 0.6, and 1.0, respectively. α = 0 represents the laser heat source as a ring light, α = 0.6 represents the laser heat source as a point ring light, and α = 1.0 represents the laser heat source as a point light. The starting welding position is (0, 2, 0), and the welding speed is 200 mm / s.

[0074] A 3D geometric model was established using ABAQUS finite element simulation software. The aluminum alloy workpiece had geometric dimensions of 20 mm × 10 mm × 2 mm and was meshed with a minimum mesh size of 0.2 mm and a maximum mesh size of 1.0 mm. The total number of cells was 20,000 and the total number of nodes was 230,001. The mesh type used was an eight-node thermally coupled hexahedral element, suitable for thermomechanical coupling calculations. Material properties and boundary conditions were established, with both the initial workpiece and ambient temperatures at 20°C. The model was then submitted to the finite element software for calculations and analysis results. Figures 5-7 show longitudinal cross-sectional views of the welding temperature fields obtained using the ring-light, point-ring-light, and point-light welding heat source models, respectively, according to an embodiment of the present invention. Figures 8-10 show cross-sectional views of the welding temperature fields obtained using the ring-light, point-ring-light, and point-light welding heat source models, respectively, according to an embodiment of the present invention. The portion above 2300°C represents the keyhole during welding; the portion above 660°C represents the liquid molten pool, which forms the weld upon cooling. Similarly, the finite element software used for modeling, meshing, and simulation is not restricted.

[0075] The circular, sinusoidal, and linear oscillating welding control equations shown in formulas (4), (5), and (6)-(8) are respectively selected to finally obtain the welding temperature field and weld surface morphology under different oscillation forms. Figure 11 shows the welding temperature field and weld surface morphology obtained by the circular oscillating point light and heat source model of the embodiment of the present invention, where the laser power distribution coefficient α = 1.0, the oscillation circle radius r = 2 mm, and the oscillation period T = 0.01 s. Figure 12 shows the welding temperature field and weld surface morphology obtained by the sinusoidal oscillating point light and heat source model of the embodiment of the present invention, where the laser power distribution coefficient α = 1.0, the oscillation amplitude r = 2 mm, and the oscillation period T = 0.02 s. Figure 13 shows the weld surface morphology of the welding temperature field obtained using the linear oscillating point light heat source model according to an embodiment of the present invention, with a laser power distribution coefficient α = 1.0, an amplitude r = 2 mm, and round-trip speeds v1 = 400 mm / s and v2 = -400 mm / s. It can be understood that although the oscillating welding model according to the embodiment of the present invention does not employ a point ring light (0 < α < 1), this is because the weld track can be visually visualized using a point light with a smaller weld width, while the weld track can be visually visualized using a point ring light with a larger weld width. However, this does not affect the use of the point ring light in the circular, sinusoidal, and linear oscillating welding heat source models. The numerical values ​​corresponding to the different colored icons in the image represent temperature values ​​in degrees Celsius.

[0076] By establishing a heat source model for spot-ring laser welding, this invention effectively simulates the energy distribution of the spot-ring beam pattern. The laser power ratio of the spot and ring beams can be adjusted in any proportion, and the defocus of the spot and ring beams can be independently controlled. Spot parameters such as the spot diameter and the ring beam diameter can be used to effectively express the heat flux density distribution. This heat source modeling method provides a powerful reference for accurately simulating the temperature, stress, and deformation fields of spot-ring laser welding. Combined with the control of the welding path, this invention can be widely applied to finite element simulations of spot-ring laser linear welding and oscillating welding.

[0077] Example 2

[0078] The second aspect of the present invention provides a spot ring laser welding system, which includes a spot ring laser, a spot ring laser fiber, a welding head, and a computing unit. The spot ring laser is used to generate a spot ring laser and inject the spot ring laser into the welding head through the spot ring laser fiber. The welding head is provided with a motor and a control unit. The control unit controls the motor to swing according to a set swing trajectory. The computing unit includes a memory, a processor, and a communication bus. The communication bus realizes the connection and communication between the processor and the memory. The processor executes one or more programs stored in the memory. The computing unit is used for finite element simulation calculation and process optimization, and feeds back the simulation results to the control unit for setting the swing trajectory and swing parameters, thereby realizing the steps of the method for establishing the spot ring laser welding heat source model in the above-mentioned embodiment 1.

[0079] Example 3

[0080] In the third aspect of the present invention, an embodiment of the present application also provides a computer-readable storage medium, which stores one or more programs, and the one or more programs can be executed by one or more processors to run any step of the method for establishing a point ring laser welding heat source model as in the above-mentioned embodiment 1.

[0081] The above schematically describes the invention and its implementation methods. This description is not restrictive. Without departing from the spirit or basic features of the invention, the invention can be implemented in other specific forms. What is shown in the accompanying drawings is only one of the implementation methods of the invention. The actual structure is not limited to this. Any figure mark in the claims should not limit the claims involved. Therefore, if a person of ordinary skill in the art is inspired by it and designs a structural method and embodiment similar to the technical solution without creativity without departing from the purpose of the invention, they should all fall within the scope of protection of the present invention. In addition, the word "including" does not exclude other elements or steps, and the word "one" before an element does not exclude the inclusion of "multiple" elements. The multiple elements stated in the product claim can also be implemented by one element through software or hardware. Words such as first and second are used to indicate names and do not indicate any specific order.

Claims

1. A method for establishing a point-ring laser welding heat source model, characterized in that: The spot-ring laser consists of the spot light of the central laser body heat source and the ring light of the annular laser surface heat source. The control equations of the spot-ring laser welding heat source are shown in Formulas (1) and (2) as follows: In formulas (1) and (2), q Total (x, y, z) represents the total heat flux density function of the point-ring laser welding heat source, (x, y, z) represents the coordinates of the global coordinate system, α represents the laser power distribution coefficient, which is the proportion of the power of the point light in the point-ring laser, Q represents the total input laser power, β represents the heat flux concentration coefficient of the central laser, γ represents the heat flux concentration coefficient of the annular laser, H represents the effective heating depth of the volume heat source, and there is a heat source heating effect in the heat source depth range of [-H, 0]. The spot parameters include r v 、r s 、r1 and r2, r v represents the effective heating radius of the central laser volume heat source, and the subscript v represents the volume heat source; r s represents the position where the heat flux density of the annular laser surface heat source is the largest, and the subscript s represents the surface heat source; the effective heating range of the annular laser surface heat source is [r1, r2].

2. The method for establishing a point-ring laser welding heat source model according to claim 1, wherein, It includes the following steps: Establish a point-ring laser welding heat source model: The control equations of the point-ring laser welding heat source are shown in Formulas (1) and (2); Establish a welding path equation: The welding path equation is one or more of a linear welding control equation, a circular swing welding control equation, a sine swing welding control equation, and a linear swing welding control equation; Select the required welding path form, and substitute the welding control equation corresponding to the welding path form into the control equation (1) of the welding heat source to obtain the moving equation of the point-ring laser welding heat source model.

3. The method for establishing a point-ring laser welding heat source model according to claim 2, wherein, It further includes the following steps: Write a code program for the point-ring laser welding moving heat source model according to the moving equation of the point-ring laser welding heat source model, and generate welding heat source data and pictures, and the pictures include the peak value of the heat flux density of the heat source.

4. The method for establishing a point-ring laser welding heat source model according to claim 3, characterized in that The peak value range of the heat flux density of the heat source is 10 6 -10 7 W / cm 2 .

5. The method for establishing a point-ring laser welding heat source model according to claim 4, characterized in that: Establish the straight-line welding control equation as shown in Equation (3): In Formula (3), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, and t represents the welding time; the welding trajectory is a straight line.

6. The method for establishing a point-ring laser welding heat source model according to claim 4, characterized in that, Establish the circular swing welding control equation as shown in Equation (4): In Formula (4), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, t represents the welding time, r represents the radius of the swing circle, and T represents the swing period of the swing circle; the welding trajectory is a helix.

7. The method for establishing a point-ring laser welding heat source model according to claim 4, characterized in that The sine swing welding control equation is established as shown in Equation (5): In Formula (5), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the welding starting position, v represents the welding speed, t represents the welding time, r represents the amplitude of the sine swing, and T represents the swing period of the sine swing; the welding trajectory is a sine curve.

8. The method for establishing a point-ring laser welding heat source model according to claim 4, characterized in that, The straight-line swing welding control equations are established as shown in equations (6)-(8): In formulas (6)-(8), (x, y, z) represents the coordinates of the global coordinate system, (x0, y0, z0) represents the coordinates of the starting position of welding, v represents the welding speed, t represents the welding time, and r represents the amplitude of the linear oscillation. During one oscillation period The reciprocating speeds within are v1 and v2 respectively. When v1 = v2, the welding trajectory is an isosceles triangular waveform.

9. The method for establishing a point-ring laser welding heat source model according to any one of claims 1-8, characterized in that, A partial differential equation for heat conduction of a three-dimensional solid with a heat source and a transient temperature field is also established, and thermo-mechanical coupling calculations are performed. The partial differential equation for heat conduction of the three-dimensional solid with a heat source and a transient temperature field is shown in Equation (9) as follows: In Equation (9), T represents the transient temperature of the material, t represents the welding and cooling time, k represents the thermal conductivity of the material, ρ represents the material density, and c p represents the specific heat of the material.

10. A dot-ring laser welding system, comprising a dot-ring laser, a dot-ring laser optical fiber, a welding head and a calculation unit; characterized in that, Wherein: The point-ring laser is used to generate point-ring laser, and the point-ring laser is injected into the welding head through the point-ring laser optical fiber; The welding head is provided with a motor and a control unit, and the control unit controls the motor to swing according to the set swing trajectory; The calculation unit includes a memory, a processor, and a communication bus; The communication bus realizes the connection and communication between the processor and the memory, and the processor executes one or more programs stored in the memory; The calculation unit is used for finite element simulation calculation and process optimization, and feeds back the simulation results to the control unit for setting the swing trajectory and swing parameters to run the method for establishing a point-ring laser welding heat source model according to any one of claims 1-9.

11. A computer-readable storage medium storing one or more programs, characterized in that, The one or more programs can be executed by one or more processors to run the method for establishing a point-ring laser welding heat source model according to any one of claims 1-9.

Images