Outer-layer focus rotation auxiliary high-power laser hybrid welding device

Abstract

The invention provides an outer-layer focus rotation auxiliary high-power laser hybrid welding device, and belongs to the technical field of laser welding, the outer-layer focus rotation auxiliary high-power laser hybrid welding device comprises a vertical light path system, an L-shaped light path system and a composite light path system, the vertical light path system comprises a first optical fiber laser, a first collimating lens and a light beam guiding element which are sequentially arranged from top to bottom; the L-shaped optical path system comprises a second optical fiber laser, a second collimating lens and a reflector which are sequentially arranged from top to bottom; the composite light path system comprises a beam combiner and a focusing lens from top to bottom, the beam combiner is used for combining laser beams from the vertical light path system and the L-shaped light path system, and the focusing lens is used for focusing the combined laser beams to the surface of a workpiece to be welded. According to the outer-layer focus rotation auxiliary high-power laser hybrid welding device, the problems that in the laser welding process, the stability of a key hole is poor and the like can be solved, and the outer-layer focus rotation auxiliary high-power laser hybrid welding device is suitable for laser welding of metal materials.

Description

Technical Field

[0001] The invention relates to the technical field of laser welding, and in particular to a high-power laser composite welding device assisted by outer layer focus rotation. Background Art

[0002] High-power fiber lasers have attracted close attention from many scholars in the manufacturing field due to their significant advantages such as small size, excellent beam quality, low operating cost and high electro-optical conversion efficiency. Especially in the field of welding manufacturing, high-power fiber laser welding technology has become one of the most popular research directions in the 21st century. In recent years, this technology has made rapid progress and has shown broad application potential in many key fields such as aerospace, rail transportation, and automobile manufacturing.

[0003] However, during laser deep penetration welding, the keyhole is often affected by the imbalance of energy and pressure, which increases the possibility of keyhole collapse and pore formation. In order to meet this challenge, focus rotation laser technology has been cleverly introduced into the laser welding process. Through high-frequency rotating laser focus, this technology can balance the input of laser energy and optimize the flow behavior of the molten pool, thereby ensuring the stability of the welding process and generating high-quality welds without defects such as spatter, cracks, and pores.

[0004] Nevertheless, while the focus rotation laser improves the welding stability and quality, it also brings about the problem of a significant decrease in laser penetration ability, which in turn inhibits the improvement of weld penetration depth. In order to overcome this limitation, the present invention proposes an outer focus rotation assisted high-power laser composite welding device. During the welding process, the method uses an inner layer of high-power fiber laser beam to form a keyhole, while the outer layer of low-power fiber laser beam performs a uniform rotation motion on the keyhole wall to accurately control the laser-induced vaporization steam on the keyhole wall. This composite welding method not only makes the keyhole wall more uniformly stressed and reduces the risk of collapse, but also further improves the stability of the welding process. Compared with traditional laser welding methods, this composite welding method not only has a more stable process, but also has higher quality welds and a lower risk of defect formation, such as pores, collapses and cracks. This innovative technology provides a new way to improve welding quality and efficiency, and is expected to play a greater role in the future manufacturing field. Summary of the invention

[0005] The purpose of the present invention is to provide an outer layer focus rotation assisted high-power laser composite welding device, which can solve the problem of poor keyhole stability during laser welding and is suitable for laser welding of metal materials.

[0006] To achieve the above-mentioned purpose, the present invention provides an outer focus rotation assisted high-power laser hybrid welding device, comprising a vertical optical path system, an L-shaped optical path system and a composite optical path system, wherein the vertical optical path system comprises a first optical fiber laser, a first collimating lens and a beam guiding element arranged in sequence from top to bottom, wherein the first collimating lens and the beam guiding element are installed to be perpendicular to the central axis of the vertical optical path system; the L-shaped optical path system comprises a second optical fiber laser, a second collimating lens and a reflector arranged in sequence from top to bottom, wherein the second collimating lens is installed to be perpendicular to the central axis of the L-shaped optical path system, and the reflector is installed at an angle of 45° to the central axis of the L-shaped optical path system; the composite optical path system comprises a beam combining mirror and a focusing lens from top to bottom, wherein the beam combining mirror is installed at an angle of 45° to the central axis of the composite optical path system, and is used to combine the laser beams from the vertical optical path system and the L-shaped optical path system, and the focusing lens is installed at an angle of 90° to the central axis of the composite optical path system, and is used to focus the combined laser beam onto the surface of the workpiece to be welded; The light beam guiding element is a scanning galvanometer or a wedge mirror.

[0007] Preferably, the first fiber laser generates a low-power fiber laser beam with a laser power of 0.1-0.5 kW, and the low-power fiber laser beam passes through a first collimating lens, a beam guiding element, a beam combining mirror and a focusing lens in sequence.

[0008] Preferably, the second fiber laser generates a high-power fiber laser beam with a laser power of 2-15 kW, and the high-power fiber laser beam passes through a second collimating lens, a reflector, a beam combining mirror and a focusing lens in sequence.

[0009] Preferably, the low-power fiber laser beam forms a low-power focused rotating laser beam after passing through the beam guiding element.

[0010] Preferably, the coating of the beam combining mirror has a transmittance of 1020-1090 nm and a reflectivity of 400-500 nm.

[0011] Preferably, the rotation frequency of the low-power focused rotating laser beam is 10-20000 Hz.

[0012] Therefore, the present invention adopts the above-mentioned outer layer focus rotation auxiliary high-power laser hybrid welding device, and the beneficial technical effects are as follows: The present invention integrates the inner layer high-power laser and the outer layer low-power fiber laser into a whole, realizing coaxial focus rotation-assisted high-power laser composite welding based on keyhole wall regulation. During welding, the inner layer high-power fiber laser beam forms a keyhole, and the outer layer low-power fiber laser beam performs uniform rotation on the keyhole wall. The keyhole wall laser is regulated to cause vaporized steam, so that the keyhole wall is more evenly stressed and less likely to collapse, thereby improving the stability of the welding process. Compared with the traditional laser welding method, the welding process is stable, the obtained weld quality is higher, and defects such as pores, collapse and cracks are not easily formed. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic structural diagram of an outer layer focus rotation assisted high power laser composite welding device of the present invention; Figure 2 The cross section of the weld produced by the conventional laser welding method; Figure 3 The cross section of the weld produced by the device of the present invention is shown in FIG.

[0014] Reference numerals 1. Vertical optical path system; 2. Low-power fiber laser beam; 3. First collimating lens; 4. Beam guiding element; 5. Low-power focused rotating laser beam; 6. Beam combining mirror; 7. Focusing lens; 8. Welding seam; 9. Workpiece to be welded; 10. Composite optical path system; 11. Reflector; 12. Second collimating lens; 13. High-power fiber laser beam; 14. L-shaped optical path system; 15. First fiber laser; 16. Second fiber laser. DETAILED DESCRIPTION

[0015] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0016] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0017] Embodiment 1 like Figure 1 As shown, the present invention provides an outer layer focus rotation assisted high-power laser composite welding device, including a vertical optical path system 1, an L-shaped optical path system 14 and a composite optical path system 10.

[0018] The vertical optical path system 1 includes a first optical fiber laser 15, a first collimating lens 3 and a beam guiding element 4 which are arranged in sequence from top to bottom. The first collimating lens 3 and the beam guiding element 4 are installed to be perpendicular to the central axis of the vertical optical path system 1.

[0019] The L-shaped optical path system 14 includes a second fiber laser 16, a second collimating lens 12 and a reflector 11 arranged in sequence from top to bottom. The second collimating lens 12 is installed to be perpendicular to the central axis of the L-shaped optical path system 14, and the reflector 11 is installed at an angle of 45° to the central axis of the L-shaped optical path system 14.

[0020] The composite optical path system 10 includes a beam combiner 6 and a focusing lens 7 from top to bottom. The beam combiner 6 is installed at an angle of 45° to the central axis of the composite optical path system 10, and is used to combine the laser beams from the vertical optical path system 1 and the L-shaped optical path system 14. The focusing lens 7 is installed at an angle of 90° to the central axis of the composite optical path system 10, and is used to focus the combined laser beam onto the surface of the workpiece 9 to be welded.

[0021] The beam guiding element 4 is a scanning galvanometer or a wedge mirror.

[0022] The first fiber laser 15 generates a low-power fiber laser beam 2 with a laser power of 0.1-0.5 kW. The low-power fiber laser beam 2 passes through the first collimating lens 3, the beam guiding element 4, the beam combining mirror 6 and the focusing lens 7 in sequence.

[0023] The low-power fiber laser beam 2 passes through the beam guide element 4 to form a low-power focused rotating laser beam 5. The rotation frequency of the low-power focused rotating laser beam 5 is 10-20000 Hz.

[0024] The second fiber laser 16 generates a high-power fiber laser beam 13 with a laser power of 2-15 kW. The high-power fiber laser beam 13 passes through the second collimating lens 12, the reflector 11, the beam combining mirror 6 and the focusing lens 7 in sequence.

[0025] The coating of the beam combiner 6 has a transmittance of 1020-1090 nm and a reflectivity of 400-500 nm.

[0026] The method of using the above device is as follows: Step S1, the high-power fiber laser beam 13 passes through the second collimating lens 12 to form a first collimated beam, and the first collimated beam is reflected by the reflector 11, passes through the beam combiner 6, and then passes through the focusing lens 7 to reach the surface of the workpiece 9 to be welded to form a keyhole; Step S2, the low-power fiber laser beam 2 passes through the first collimating lens 3 to form a second collimated beam, and the second collimated beam passes through the beam guiding element 4 to form a low-power focused rotating laser beam 5, and then passes through the beam combining mirror 6 and the focusing lens 7 to reach the wall of the keyhole; Step S3, the low-power focused rotating laser beam 5 performs uniform rotating motion on the wall of the keyhole, and the laser on the keyhole wall is regulated to evaporate steam, thereby forming an excellent weld 8.

[0027] like Figure 2 and Figure 3 The figures are the cross sections of the weld produced by the conventional laser welding method and the cross sections of the weld produced by the device of the present invention. It can be seen that the quality of the cross section of the weld produced by the device of the present invention is higher than that of the conventional method.

[0028] It is worth noting that the contents not elaborated in detail in the present invention are all prior art and are well known to those skilled in the art.

[0029] Therefore, the present invention adopts the above-mentioned outer focus rotation assisted high-power laser composite welding device to solve the problem of poor keyhole stability during laser welding, and is suitable for laser welding of metal materials.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. An outer focus rotation assisted high-power laser composite welding device, comprising a vertical optical path system, an L-shaped optical path system and a composite optical path system, characterized in that: The vertical optical path system includes a first optical fiber laser, a first collimating lens and a beam guiding element arranged in sequence from top to bottom, and the first collimating lens and the beam guiding element are installed to be perpendicular to the central axis of the vertical optical path system; the L-shaped optical path system includes a second optical fiber laser, a second collimating lens and a reflector arranged in sequence from top to bottom, and the second collimating lens is installed to be perpendicular to the central axis of the L-shaped optical path system, and the reflector is installed at an angle of 45° to the central axis of the L-shaped optical path system; the composite optical path system includes a beam combining mirror and a focusing lens from top to bottom, and the beam combining mirror is installed at an angle of 45° to the central axis of the composite optical path system, and is used to combine the laser beams from the vertical optical path system and the L-shaped optical path system, and the focusing lens is installed at an angle of 90° to the central axis of the composite optical path system, and is used to focus the combined laser beam onto the surface of the workpiece to be welded; The light beam guiding element is a scanning galvanometer or a wedge mirror.

2. The outer layer focus rotation assisted high power laser hybrid welding device according to claim 1, characterized in that: The first fiber laser generates a low-power fiber laser beam with a laser power of 0.1-0.5 kW. The low-power fiber laser beam passes through a first collimating lens, a beam guiding element, a beam combining mirror and a focusing lens in sequence.

3. The outer layer focus rotation assisted high power laser hybrid welding device according to claim 2, characterized in that: The second fiber laser generates a high-power fiber laser beam with a laser power of 2-15 kW. The high-power fiber laser beam passes through a second collimating lens, a reflector, a beam combining mirror and a focusing lens in sequence.

4. The outer layer focus rotation assisted high power laser hybrid welding device according to claim 3, characterized in that: The low-power fiber laser beam forms a low-power focused rotating laser beam after passing through the beam guiding element.

5. The outer layer focus rotation assisted high power laser hybrid welding device according to claim 4, characterized in that: The transmittance of the coating of the beam combining mirror is 1020-1090nm, and the reflectivity is 400-500nm.

6. The outer layer focus rotation assisted high power laser hybrid welding device according to claim 5, characterized in that: The rotation frequency of the low-power focused rotating laser beam is 10-20000 Hz.

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