Welding laser

Abstract

The utility model discloses a welding laser which comprises a plurality of first-type laser modules, first-type output optical fibers of the first-type laser modules are arranged in an array mode to form a first array, and second-type output optical fibers of the first-type laser modules are arranged in an array mode to form a second array. A plurality of second-type laser modules, second-type output optical fibers of the second-type laser modules are sequentially arranged around the first array to form a second array; the light beam control module is connected with each first type of laser module and is used for controlling the output time sequence of each first type of laser module to form a swinging light beam; the light beam control module is further connected with the second type laser modules and controls the second type laser modules to form annular light beams. The welding laser provided by the utility model can form a composite light spot consisting of swinging optical fiber laser and semiconductor laser without adopting a complex optical element.

Description

Technical Field

[0001] The utility model relates to the field of laser processing, in particular to a welding laser. Background Art

[0002] In laser deep-penetration welding, since the wavelength of traditional fiber lasers is in the near-infrared light band, metals such as copper and aluminum alloy have a high reflectivity to near-infrared light beams. The absorption rate of laser energy when the material is in a solid state and in a molten liquid state is quite different, which makes the welding process unstable. To solve this problem, a welding scheme using semiconductor composite spots for auxiliary welding has emerged. In this scheme, the semiconductor spot first preheats the surface of the solid material to form a molten pool, and then the fiber laser is applied to the molten pool to form a keyhole. This can effectively avoid the problem of large differences in energy absorption rates and ensure the stability of the welding process.

[0003] However, when the keyhole is formed, it is often in an unstable state due to the combined effects of the recoil pressure of the liquid metal erupting in the molten pool and the surface tension of the molten pool surface, and is therefore prone to collapse, which forms spatter and pores that affect the welding quality. In order to eliminate the keyhole, an oscillating laser method is used to make the keyhole oscillate relative to the molten pool. The stirring effect of the laser on the molten pool can effectively eliminate pores, effectively refine grains, effectively eliminate solidification cracks, and improve weld strength and welding quality.

[0004] Taking the invention patent with Chinese invention publication number CN117600653A as an example, it uses a blue light laser (semiconductor laser) and a fiber laser for composite processing. The blue light laser is used to preheat the material, and the fiber laser is controlled by a galvanometer system to swing during welding. Among them, in this scheme, in order to composite the blue light laser and the fiber laser, it is necessary to use a beam combining prism to combine the two light beams. The beam combining element is expensive and will produce serious return light. In order to swing the fiber laser, it is necessary to use a galvanometer system. The galvanometer system is expensive and is prone to temperature drift due to the return light, resulting in unstable control. Utility Model Content

[0005] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a welding laser that can form a composite light spot composed of a swinging fiber laser and a semiconductor laser without using complex optical elements.

[0006] To achieve the above objectives and other related objectives, the present application provides a welding laser, comprising:

[0007] A plurality of first-type laser modules, wherein the first-type output optical fibers of the first-type laser modules are arranged in an array to form a first array;

[0008] A plurality of second-type laser modules, wherein the second-type output optical fibers of the second-type laser modules are sequentially arranged around the first array to form a second array;

[0009] A beam control module, connected to each of the first-type laser modules, controls the output timing of each of the first-type laser modules to form a swinging beam;

[0010] The beam control module is also connected to each of the second-type laser modules to control each of the second-type laser modules to form a ring-shaped beam.

[0011] Optionally, the beam control module further controls the output power of each of the first-type laser modules, and controls the power of the swinging beam acting at different swinging positions.

[0012] Optionally, the beam control module further controls the output power of each of the second-type laser modules to control the power distribution of the annular beam.

[0013] Optionally, the first-type output optical fibers are arranged in a regular hexagonal array, a circular array, or a strip array.

[0014] Optionally, each of the first-type output optical fibers outputs a single-mode laser; and each of the second-type output optical fibers outputs a multi-mode laser.

[0015] Optionally, a laser wavelength output by the first type laser module is different from a laser wavelength output by the second type laser module.

[0016] Optionally, the first type laser module adopts a fiber laser, and the second type laser module adopts a semiconductor laser.

[0017] Optionally, the first type laser module adopts a green light fiber laser, and the second type laser module adopts a blue light semiconductor laser.

[0018] Optionally, a plurality of mutually spaced first-type output optical fibers in the first array simultaneously output to form a plurality of swinging light beams.

[0019] Optionally, a plurality of adjacent first-type output optical fibers in the first array are output simultaneously and bundled to form the swinging light beam.

[0020] As described above, the present application provides a welding laser, which is formed by arranging a first output optical fiber array to form a first array, and the output optical fibers in the first array are intermittently output at different spatial positions according to a time sequence, forming a swinging light beam that swings at a high speed at a focusing center at a preset focal plane, and the swinging light beam with high power density can stir the molten pool and improve the welding quality; a second output optical fiber is arranged in a ring outside the first array, and the second output optical fiber arranged in a ring outside the first array outputs a ring light beam, and the spatial position of the ring light beam is fixed, which can preheat and anneal the material; based on the arrangement and output control of the first array and the second array, even if a beam combining prism and a galvanometer are not used, a composite light spot composed of a swinging optical fiber laser and a semiconductor laser can be formed. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0022] Figure 1 Schematic diagram of the structure of the welding laser provided in the embodiment.

[0023] Figure 2 It is a schematic diagram of the structure of array optical fibers in which the first array and the second array provided in the embodiment are both arranged in a regular hexagon.

[0024] Figure 3 It is a schematic diagram of the structure of array optical fibers in which the first array and the second array provided in the embodiment are arranged in different shapes.

[0025] Figure 4 It is a schematic diagram of the structure of an array optical fiber in which the first array provided in the embodiment is arranged in a square array.

[0026] Figure 5 It is an output timing for outputting a circular oscillating light spot path along the first array of the weld provided in the embodiment.

[0027] Figure 6 It is a flow chart of the composite welding method provided in the embodiment. DETAILED DESCRIPTION

[0028] In order to facilitate the understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on another element or there can be one or more centered elements therebetween. When an element is described as "connected" to another element, it can be directly connected to another element or there can be one or more centered elements therebetween. The orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "bottom" and the like used in this specification is based on the orientation or positional relationship shown in the accompanying drawings, only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" and the like are used only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0029] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0030] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0031] The present application proposes a welding laser 1, the welding beam formed by the laser includes a swinging beam with high-speed periodic motion and a ring beam located on the periphery of the motion path of the swinging beam. Among them, the ring beam, for example, uses a semiconductor laser in the blue light band. Under normal temperature, materials such as copper and aluminum alloy that are highly reflective to near-infrared lasers have a high absorption rate to blue light lasers, and can melt metals to form a molten pool under the irradiation of a relatively low-power blue light laser. After the molten pool is formed, the temperature of the molten liquid in the molten pool is relatively high, and the absorption rate of the near-infrared beam increases. The use of a fiber laser to form a laser in the near-infrared band can effectively utilize the characteristics of the fiber laser that can form a high-power laser and a high power density to form a molten pool with a large depth-to-width ratio, and the swinging beam can stir the molten pool, reduce the incidence of bubbles and spatters during welding, and effectively improve the welding quality. It should be noted that the laser 1 provided in the present application is not only suitable for materials such as copper, gold, and aluminum that are highly reflective to near-infrared light, but also suitable for conventional stainless steel and carbon steel processing.

[0032] like Figure 1 and Figure 2As shown, the welding laser 1 provided in this embodiment includes: a plurality of first-type laser modules 10a and a plurality of second-type laser modules 10b. The first-type laser modules 10a output through a first-type output optical fiber 11a, and the second-type laser modules 10b output through a second-type output optical fiber 11b; Figure 2 As shown, a plurality of first type output optical fibers 11a are arranged in an array to form a first array 12a, and a plurality of second type output optical fibers 11b are arranged around the first array 12a to form a second array 12b. The first array 12a and the second array 12b are coupled to the laser output head 20 according to a preset arrangement shape.

[0033] In this embodiment, the first type of output optical fibers are of the same model, forming a first array 12a, which outputs, for example, optical fiber lasers; the second type of output optical fibers are of the same model, forming a second array 12b, which outputs, for example, semiconductor lasers. The first array 12a is located inside the ring formed by the second array 12b. The special combination and arrangement of the two arrays enables the laser 1 to form a beam composed of a semiconductor laser and an optical fiber laser. Furthermore, by controlling the output timing of each laser module in the first array 12a, the optical fiber laser can also be controlled to swing. Therefore, there is no need to set up a complex beam combining element and galvanometer system in the subsequent laser output head 20, and a composite light spot composed of a swinging optical fiber laser and a semiconductor laser can be formed to reduce costs, reduce system return light, and improve the control accuracy of the swinging light beam. Figures 2 to 4 As shown, the first array 12a can be a regular hexagonal array, a circular array (not shown), a triangular array (not shown), a strip array, etc., and accordingly, the second array 12b is arranged around the periphery of the first array 12a. In addition, the second array 12b can be formed in the same shape as the first array 12a, forming an array of the same shape, such as Figure 2 The combination of the regular hexagonal first array 12a and the hexagonal second array 12b shown in FIG. 1 may also be different from the shape formed by the first array 12a, for example, Figure 3 The illustrated embodiment is a combination of a first array 12a of regular hexagons and a second array 12b of circles.

[0034] like Figure 1 As shown, a beam control module 30 is provided, and the beam control module 30 is connected to each of the first-type laser modules. Since each laser module can be turned on and off independently, the beam control module 30 can control the output timing of each first-type output optical fiber in the first array 12a to control the light beam formed by the first array 12a to swing along a preset path. The relative movement speed of the swinging light beam is faster, which can expand the keyhole opening and reduce the probability of keyhole collapse, thereby reducing the probability of pore formation caused by collapse. In addition, the swinging light beam can play a role in stirring the molten pool, promoting the escape of pores, and reducing the probability of pores remaining. As an example, the first array 12a is as follows Figure 2 The regular hexagonal array shown in Figure 5 The timing shown controls the output of each first type output optical fiber in the first array 12a, and cooperates with the welding direction to form a circular swinging welding path at the weld; it is not limited to Figure 5 The circular swing welding path of the timing shown can also form a harmonic swing welding path, a triangle wave swing welding path, an 8-shaped swing welding path, an ∞-shaped swing welding path, etc. through output timing control; it is not limited to Figure 5 In the embodiment, only a single first type laser module is used for output at the same time, and multiple swinging beams can be formed at the same time, or multiple beams can be combined to form one swinging beam. For example, Figure 2 As shown, by appropriately adjusting the spacing between the first type output optical fibers and the beam divergence angle, the energy distributions of the synchronously output beams of two adjacent first type output optical fibers are superimposed on each other to form a swinging beam, and the beams formed by non-adjacent first type output optical fibers cannot be superimposed, forming two swinging beams.

[0035] At the same time, taking circular swing as an example, since the average action time of the swinging light beam at the edge of the weld is longer than the average action time at the middle of the weld, the total amount of heat received at the edge of the weld is higher, and the weld depth is deeper than that in the middle area of ​​the weld. In order to adjust the metallographic cross-section of the weld to be close to the ideal shape (U-shaped cross-section), the beam control module 30 can be used to control the time ratio of the swinging light beam acting on different positions of the weld to control the uniformity of heat input; the beam control module 30 can also be used to control the power ratio of the swinging light beam acting on different positions of the weld to control the uniformity of heat input; of course, the beam control module 30 coordinates and controls the time ratio and power ratio of the swinging light beam acting on different positions of the weld to control the uniformity of heat input.

[0036] like Figure 1As shown, the beam control module 30 is also connected to each of the second-type laser modules 10b. Each of the second-type laser modules 10b outputs simultaneously to form an annular beam; when the material is in a molten state, the laser absorption rate will be significantly improved due to the changes in its shape and temperature. The annular beam is used to act on the surface of the material to increase the temperature of the material until it melts, which can effectively reduce the drastic change in the heat absorption rate when the swinging beam acts on the solid material, thereby reducing the probability of keyhole collapse caused by large changes in periodic heat input; when the swinging beam forms a deep keyhole, the annular beam behind the keyhole can anneal the condensed tissue. Based on the same power control, the beam control module 30 can freely control the spot energy distribution of the annular beam formed by the second array. For example, the power of the annular beam on the front side of the molten pool is set to twice the power of the annular beam on the rear side of the molten pool, so as to achieve diversified spot energy distribution of the same annular beam, which is suitable for scenes with inconsistent preheating and annealing requirements.

[0037] In some embodiments, the first type laser module 10a uses a fiber laser, and the second type laser module 10b uses a semiconductor laser. The laser beam formed by the fiber laser and the laser beam output by the semiconductor laser both have the characteristics of high power, and can form a laser with better beam quality and higher power density than the semiconductor laser. Compared with the semiconductor laser, its beam is suitable for deep melting welding to form a high welding depth. In order to form a keyhole with a large depth-to-width ratio, the first type laser module 10a can use a single-mode laser. The energy distribution of the beam formed by the single-mode laser is a Gaussian distribution with high power density. In terms of contact that satisfies deep melting welding, the fiber laser, for example, uses a green fiber laser. The laser band emitted by the green fiber laser can be efficiently absorbed by high-reflective materials (materials that are highly reflective to near-infrared lasers). Compared with near-infrared lasers, the fluctuation of beam energy absorption is small, which is beneficial to welding quality; semiconductor lasers such as blue lasers, whose laser bands can also be efficiently absorbed by high-reflective materials, and have higher power, but due to the large divergence angle and low power density, are suitable for melting high-reflective materials before welding to form a molten pool and subsequent annealing.

[0038] This embodiment further provides a composite welding method, which is implemented based on the above-mentioned welding laser and includes the following steps:

[0039] S1), turning on each of the second type laser modules to form a welding molten pool on the surface of the material to be welded.

[0040] In step S1), the annular beam formed by the second type laser module is pre-irradiated to the welding material to form a welding molten pool on the surface of the welding material. The selection of the annular beam is adapted to the welding material so that the welding material can absorb the laser energy with a higher absorption rate; and when the welding is completed and the welding molten pool solidifies, the annular beam formed by the second type laser module can also control the solidification rate of the molten pool. By controlling the output power of each first type laser module, the energy distribution of the annular beam is uneven, for example, the power of the annular beam acting on the front side of the molten pool is higher, and the power of the annular beam acting on the rear side of the molten pool is lower, so as to freely adjust the solidification rate of the molten pool and affect the morphology and density of the generated grain structure.

[0041] S2), turning on at least one of the first laser modules to form a keyhole in the welding molten pool.

[0042] In step S2), the light beam formed by the first laser module is located inside the annular light beam and acts on the welding molten pool with a higher power density. The molten metal at the focused irradiation position of the light beam is evaporated to form a deep keyhole.

[0043] S3), controlling the output timing of each of the first laser modules so that the position of the keyhole changes continuously to form a swinging keyhole.

[0044] In step S3), each first laser module is, for example, Figure 5 The output is performed in the timing shown, and an oscillating light spot can be formed without the help of a galvanometer system. The keyhole also oscillates accordingly. The keyhole oscillating at a suitable frequency can stir the molten pool and reduce the bubble rate. In addition, the output power of each second laser module can be adjusted to control the depth of the keyhole oscillating to different positions, so as to form an ideal weld cross-section metallographic structure and improve the welding quality.

[0045] In summary, the welding laser described in the present application is formed by arranging a first output optical fiber array to form a first array, and the output optical fibers in the first array are intermittently output at different spatial positions according to a time sequence, forming a swinging light beam with a high-speed swinging focus center at a preset focal plane, and the swinging light beam with high power density can stir the molten pool and improve the welding quality; a second output optical fiber is arranged in a ring outside the first array, and the second output optical fiber arranged in a ring outside the first array outputs a ring light beam, and the spatial position of the ring light beam is fixed, which can preheat and anneal the material; based on the arrangement and output control of the first array and the second array, even without using a beam combining prism and a galvanometer, a composite light spot composed of a swinging optical fiber laser and a semiconductor laser can be formed. Therefore, the present application effectively overcomes the various shortcomings of the prior art and has a high industrial utilization value.

[0046] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A welding laser, characterized in that: The laser comprises: A plurality of first-type laser modules, wherein the first-type output optical fibers of the first-type laser modules are arranged in an array to form a first array; A plurality of second-type laser modules, wherein the second-type output optical fibers of the second-type laser modules are sequentially arranged around the first array to form a second array; The beam control module is connected to each of the first-type laser modules to control the output timing of each of the first-type laser modules to form a swinging beam; the beam control module is also connected to each of the second-type laser modules to control each of the second-type laser modules to form a ring beam.

2. The laser according to claim 1, characterized in that The beam control module also controls the output power of each of the first-type laser modules, and controls the power of the swinging beam when it acts at different swinging positions.

3. The laser according to claim 1, characterized in that The beam control module further controls the output power of each of the second-type laser modules and controls the power distribution of the annular beam.

4. The laser according to claim 1, characterized in that The first-type output optical fibers are arranged in a regular hexagonal array, a circular array, or a strip array.

5. The laser according to claim 1, characterized in that Each of the first-type output optical fibers outputs a single-mode laser; and each of the second-type output optical fibers outputs a multi-mode laser.

6. The laser according to claim 1, characterized in that A plurality of mutually spaced first-type output optical fibers in the first array simultaneously output a plurality of swinging light beams.

7. The laser according to claim 1, characterized in that A plurality of adjacent first-type output optical fibers in the first array output simultaneously and are bundled to form the swinging light beam.

8. The laser according to claim 1, characterized in that The wavelength of the laser output by the first type laser module is different from the wavelength of the laser output by the second type laser module.

9. The laser according to claim 8, characterized in that The first type laser module adopts a fiber laser, and the second type laser module adopts a semiconductor laser.

10. The laser according to claim 9, characterized in that The first type laser module adopts a green light fiber laser, and the second type laser module adopts a blue light semiconductor laser.

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