A multi-heat source coupled titanium alloy welding apparatus and method

Abstract

The present application relates to the technical field of metal welding and additive manufacturing, and provides a titanium alloy welding device and method coupled with multiple heat sources, the welding device comprising a ring laser system, a TIG welding system, a MIG welding system and a bypass shunt coordination control system, forming arc coupling between TIG and MIG and light arc coupling between laser and arc; the bypass shunt coordination control system is connected with the TIG welding system and the MIG welding system respectively, the bypass shunt coordination control system can shunt the main circuit current of the MIG welding system to the TIG welding system, and by adjusting the bypass current value flowing into the TIG welding system, the flexible switching of linear or curved welds is realized. The present application effectively solves the technical problems such as low wire cladding efficiency, poor adaptability, poor weld forming, uncontrollable heat input, unstable droplet transfer and the like in traditional laser additive manufacturing.

Description

Technical Field

[0001] This invention relates to the fields of metal welding and additive manufacturing technology, and more specifically, to a titanium alloy welding apparatus and method with multiple heat source coupling. Background Technology

[0002] Titanium alloys are widely used in aerospace, shipbuilding, and high-end equipment structures due to their high specific strength, excellent corrosion resistance, and good high-temperature mechanical properties. However, titanium alloys have low thermal conductivity and high surface tension in the molten state, which can easily lead to problems such as poor molten pool fluidity, insufficient melting of the welding wire, and unstable droplet transfer during welding, seriously affecting the stability and forming quality of the additive manufacturing process.

[0003] In laser-assisted wire-filled additive manufacturing technology, traditional methods typically use point lasers as the main heat source. Although point lasers have advantages such as high energy density and strong penetration, their effective area is limited and the heat input range is small, making it difficult to achieve uniform heating of the welding wire and the substrate. Especially under high-speed wire feeding conditions, defects such as insufficient wire preheating, local lack of fusion, and increased spatter often occur, limiting the improvement of cladding efficiency and weld bead formation accuracy.

[0004] To improve welding wire deposition efficiency and welding stability, researchers have explored the introduction of hybrid heat source welding processes. Among these, MIG (Metal Inert Gas) arc welding combined with laser technology is widely used, enhancing heat input control through the synergistic effect of the arc and laser. However, conventional MIG-laser hybrid processes still suffer from problems such as excessively high substrate heat input, significant impact of laser disturbance on arc stability, and strong droplet transfer directionality. This is particularly problematic in additive manufacturing of complex trajectory or curved weld seams, where precise control of the droplet landing point is difficult.

[0005] In recent years, bypass current shunting technology and multi-arc coupling concepts have been increasingly applied to the field of hybrid welding. By diverting a portion of the main current to the auxiliary electrode, the heating effect of the welding wire can be enhanced while reducing the heat input to the substrate, thereby improving melting efficiency. Simultaneously, coupling multiple circumferentially symmetrically arranged TIG (tungsten inert gas) welding torches with a central heat source helps to form a uniform thermal field distribution throughout the circumference, improving the symmetry of the molten pool and the droplet transfer behavior. However, existing technologies often rely on multiple independent laser sources or non-coaxial structural designs, resulting in complex systems, high costs, and a lack of effective means to control the stress state of the molten droplets, failing to meet the demands of high-precision, high-efficiency additive manufacturing of titanium alloys.

[0006] Chinese patent CN118989599A discloses a laser-arc coaxial heat source coupled additive manufacturing apparatus and method. The apparatus includes: a ring laser system that emits laser light and transmits it to a laser mirror group, which emits a hollow ring laser beam; a rotating tungsten inert gas (TIG) welding system, in which a rotating motor drives a fixed disk and a tungsten electrode to rotate, the fixed disk and the ring laser beam being coaxial, and the tungsten electrode passing through the interior of the ring laser beam; and a wire feeding system for conveying a metal wire to the molten pool. This apparatus achieves coupling between the TIG arc and the ring laser beam, but it still lacks consideration in improving the stability of the coupled arc, operational flexibility, and additive manufacturing accuracy.

[0007] Chinese patent CN103071935A discloses a laser-arc hybrid welding device and method based on heat input control. The device includes a laser, a laser head, an arc welding power source, a main consumable electrode welding torch, and a wire feeding mechanism. It also includes a bypass welding torch and a rheostat. The laser head is connected to the laser and positioned above the workpiece. The main consumable electrode welding torch and the bypass welding torch are symmetrically placed on either side of the laser beam formed by the laser head. The main consumable electrode welding torch is connected to the positive terminal of the arc welding power source, and the workpiece's electrical terminal is connected to the negative terminal of the arc welding power source. The bypass welding torch is connected to the negative terminal of the arc welding power source through the rheostat. This device can control the welding heat input of the laser-arc hybrid heat source, reduce the heat-affected zone and welding deformation, and improve the metallurgical properties and microstructure of the weld. Specifically, by adjusting the bypass current (using a rheostat and a current sensor to achieve closed-loop control), the heat input is rationally distributed, effectively reducing the heat-affected zone and welding deformation, and improving weld quality. However, it does not provide a collaborative control scheme for arc coupling between TIG and MIG and optical arc coupling between laser and arc, nor can it achieve active guidance of the weld bead formation position.

[0008] Therefore, it is necessary to develop a titanium alloy welding device and method with multiple heat source coupling to improve welding efficiency and solve related technical problems. Summary of the Invention

[0009] The purpose of this invention is to provide a titanium alloy welding device and method with multiple heat source coupling. This invention effectively solves the technical problems in traditional laser additive manufacturing, such as low wire cladding efficiency, poor adaptability, poor weld bead formation, uncontrollable heat input, and unstable droplet transition.

[0010] To achieve the above objectives, the present invention provides a titanium alloy welding apparatus and method with multi-heat source coupling. The technical solution of the present invention is implemented as follows:

[0011] A multi-heat-source coupled titanium alloy welding apparatus includes a ring laser system, a TIG welding system, a MIG welding system, and a bypass shunt coordination control system, forming arc coupling between TIG and MIG and optical arc coupling between laser and arc. The bypass shunt coordination control system is connected to the TIG welding system and the MIG welding system respectively. The bypass shunt coordination control system can divert the main current of the MIG welding system to the TIG welding system, and can flexibly switch between straight and curved welds by adjusting the bypass current value flowing into the TIG welding system.

[0012] Furthermore, the annular laser system forms an annular laser beam; the welding wire passes through the interior of the annular laser beam, achieving uniform circumferential heating of the welding wire.

[0013] Furthermore, the annular laser beam is a high-frequency pulsed laser, and the annular spot formed by the convergence of the annular laser beam acts stably on the necking of the molten droplet.

[0014] The welding wire is fed vertically into the molten pool to improve the precision of additive manufacturing.

[0015] Furthermore, the TIG welding system includes four TIG welding torches, each holding a tungsten electrode. The four tungsten electrodes are circumferentially and uniformly distributed around the annular laser beam to improve the stability of the coupled arc and enhance the cladding efficiency.

[0016] Furthermore, the bypass shunt coordination control system includes a shunt control module, which is used to control the main current I. Z The distribution and bypass current are controlled to flexibly switch between straight and curved weld seams; the main current I... Z The welding wire significantly improves the melting efficiency.

[0017] Furthermore, the current relationship of the welding device is as follows: I Z =I P1 +I P2 +I P3 +I P4 +I M , among which, I P1 For bypass current I, P2 For bypass current II, I P3 For bypass current three, I P4 For bypass current four, I M The substrate current; the bypass current I P1 Bypass current I P2 Bypass current three I P3 and bypass current fourI P4 The current flows to the four tungsten electrodes respectively, forming four TIG arcs; the substrate current I MIt flows to the substrate, forming the main MIG arc.

[0018] Furthermore, for straight welds, I P1 I P2 I P3 I P4 Set to equal; for curved welds, I P1 I P2 I P3 I P4 Set them to be unequal.

[0019] A method for welding titanium alloys using multiple heat source coupling, the method comprising the following steps:

[0020] S1, Substrate surface pretreatment;

[0021] S2, Installation and startup of the ring laser system;

[0022] S3, MIG welding system installation and startup;

[0023] S4, TIG welding system installation and startup;

[0024] S5, installation and startup of bypass diversion coordination control system.

[0025] Furthermore, step S2 includes:

[0026] S21, Install a ring laser system and connect to the fiber optic transmission channel;

[0027] S22, activate the ring laser system to form a ring laser beam;

[0028] S23, adjust the working distance to focus the annular laser beam into an annular spot of the desired size.

[0029] Furthermore, step S3 includes:

[0030] S31, install the MIG welding system, connect the welding wire and the bypass shunt coordination control system to form the main circuit loop;

[0031] S32, start the wire feeder.

[0032] Furthermore, step S4 includes: connecting the TIG welding torch and the bypass shunt coordination control system.

[0033] Furthermore, step S5 includes:

[0034] S51, start the bypass shunt coordination control system to achieve dynamic matching between main current and bypass current;

[0035] S52, set the target shunt current value for each TIG branch;

[0036] S53 monitors and adjusts the current distribution ratio in real time.

[0037] Compared with existing technologies, the titanium alloy welding device and method with multiple heat source coupling described in this invention have the following advantages:

[0038] 1. A bypass TIG arc, a main MIG arc, and a hollow annular laser beam achieve multi-field synergistic coupling, forming a highly stable composite coupled arc. This structure not only realizes arc-arc coupling between the TIG and MIG arcs but also enhances the light-arc coupling effect between the laser and the arc through laser guidance and energy injection into the plasma. The synergistic effect of multiple energy fields (thermal, electromagnetic, and fluid) significantly improves the coupling strength and enhances the overall stability of the heat source; simultaneously, the energy density and effective range of the composite heat source are significantly increased, and it also has a preheating function for the welding wire, effectively improving the welding wire melting efficiency and cladding rate.

[0039] 2. The circumferentially symmetrical structure allows welding in any orientation, enhancing automation compatibility. Four TIG electrodes are circumferentially symmetrically distributed around the welding wire, forming four bypass arcs that achieve full-circumferential arc coupling outside the welding wire, significantly improving the arc's encirclement of the welding wire and the uniformity of heat input. Compared to single TIG electrodes or asymmetrically arranged composite arcs, this structure offers a higher degree of coupling and a more symmetrical heat field distribution, completely eliminating the direction dependence of the welding process and improving process adaptability.

[0040] 3. Optimized welding wire and annular laser beam setup improves weld bead formation. The welding wire passes through the interior of the annular laser beam, achieving uniform circumferential heating and eliminating welding directionality; the welding wire is fed vertically into the molten pool, ensuring consistent droplet landing points to improve additive manufacturing precision; the annular laser beam is a high-frequency pulsed laser, and the annular spot of the beam acts stably on the necking point of the molten droplet, which helps improve and control the droplet transition process.

[0041] 4. The current flowing through the TIG welding torch is a bypass current diverted from the main MIG current. The bypass TIG arc and the main welding wire achieve strong electromagnetic coupling through a shared current loop, significantly enhancing the synergistic effect of the multi-arc system. At the same time, since part of the current is diverted through the TIG path, the main current flowing through the substrate is reduced accordingly, thereby effectively reducing the heat input to the substrate and shrinking the heat-affected zone, which is beneficial for welding and additive manufacturing of precision components such as thin-walled or heat-sensitive structures.

[0042] 5. By independently adjusting the bypass current of each TIG welding torch, the asymmetry of the electromagnetic force distribution around the molten droplet can be dynamically controlled, thereby applying a controllable deflection force and achieving precise control of the droplet transition direction and landing point. This function makes the weld bead formation position programmable, making it particularly suitable for high-precision additive manufacturing and repair operations of curved welds, variable curvature paths, and three-dimensional spatial structures. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the titanium alloy welding device described in Embodiment 1 of the present invention. Figure 1 ;

[0044] Figure 2 This is a schematic diagram of the titanium alloy welding device described in Embodiment 1 of the present invention. Figure 2 .

[0045] Explanation of reference numerals in the attached figures:

[0046] 1. Coupled arc; 101. TIG arc one; 102. TIG arc two; 103. TIG arc three; 104. TIG arc four; 2. TIG welding torch one; 201. Tungsten electrode one; 3. TIG welding torch two; 301. Tungsten electrode two; 4. TIG welding torch three; 401. Tungsten electrode three; 5. TIG welding torch four; 501. Tungsten electrode four; 6. Molten droplet; 7. Welding wire; 8. Substrate; 9. Coordination controller; 10. TIG power supply one; 11. TIG power supply two; 12. TIG power supply three; 13. TIG power supply four; 14. MIG power supply; 15. Laser; 16. Wire feeder; 17. Annular laser beam; 18. Laser mirror assembly. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the described embodiments are only some, not all, of the embodiments of this invention. The specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0048] Example 1

[0049] A multi-heat-source coupled titanium alloy welding device includes a ring laser system, a TIG welding system, a MIG welding system, and a bypass shunt coordination control system. The bypass TIG arc, the main MIG arc, and the hollow ring laser beam 17 achieve multi-field synergistic coupling, forming a highly stable composite coupled arc 1. This setup not only achieves arc-arc coupling between the TIG and MIG arcs but also enhances the light-arc coupling effect between the laser and the arc through laser guidance and energy injection of the plasma. The synergistic effect of multiple energy fields (thermal, electromagnetic, and fluid) significantly improves the coupling strength and enhances the overall stability of the heat sources; simultaneously, the energy density and effective range of the composite heat source are significantly increased, and it also has a preheating function for the welding wire 7, effectively improving the melting efficiency and cladding rate of the welding wire 7.

[0050] The ring laser system consists of a laser 15, an optical fiber, a laser mirror assembly 18, and a ring laser beam 17. The laser 15 is connected to the laser mirror assembly 18 via an optical fiber. After being transmitted through the optical fiber to the laser mirror assembly 18, the laser beam is shaped into a hollow ring laser beam 17. The ring laser beam 17 irradiates the substrate 8 perpendicularly, uniformly heating the substrate 8 and melting it to form a molten pool, thus achieving precise heat input and molten pool control in the welding area.

[0051] The annular laser beam 17 is a high-frequency pulsed laser, which, after focusing, forms an annular spot on the welding wire 7. The spot is located 10-15 mm above the plane of the area to be welded. Within a suitable process parameter window, the annular spot acts stably on the necking region of the molten droplet 6.

[0052] High-frequency pulse excitation causes the annular spot to drive the molten droplet 6 to generate high-frequency vibration, which effectively overcomes surface tension and facilitates the molten droplet 6 to detach from the end of the welding wire 7, thereby improving and controlling the transition process of the molten droplet 6.

[0053] The annular light spot preheats the welding wire 7, increases the initial energy of the molten droplet 6, accelerates its heating and melting rate, and can improve the transition frequency of the molten droplet 6.

[0054] The welding wire 7 passes through the interior of the annular laser beam 17, ensuring that the laser energy is evenly distributed around the welding wire 7, achieving uniform circumferential heating. This avoids the uneven energy distribution problem caused by the unilateral heating of traditional point lasers and eliminates welding directionality. Preferably, the welding wire 7 passes through the center of the annular laser beam 17, achieving precise distribution of laser energy around the welding wire 7, which can significantly promote the transfer of molten droplets 6 and improve welding accuracy.

[0055] The welding wire 7 is fed vertically into the molten pool, which makes the landing point of the molten droplets 6 consistent, which is beneficial to improve the formation of the additive weld and improve the precision of additive manufacturing.

[0056] A TIG welding system includes a TIG power source and a TIG welding torch. For example... Figure 1 As shown, the four TIG power supplies are TIG Power Supply 1 (10), TIG Power Supply 2 (11), TIG Power Supply 3 (12), and TIG Power Supply 4 (13). The positive terminal of each TIG power supply is connected to a bypass shunt coordinator 9. The four TIG power supplies are connected to four TIG welding torches: TIG Welding Torch 1 (2), TIG Welding Torch 2 (3), TIG Welding Torch 3 (4), and TIG Welding Torch 4 (5). Each TIG welding torch holds a tungsten electrode: Tungsten Electrode 1 (201), Tungsten Electrode 2 (301), Tungsten Electrode 3 (401), and Tungsten Electrode 4 (501). The four tungsten electrodes form four TIG arcs: TIG Arc 1 (101), TIG Arc 2 (102), TIG Arc 3 (103), and TIG Arc 4 (104).

[0057] Four TIG electrodes are circumferentially symmetrically distributed around the welding wire 7, forming four bypass arcs that achieve full-circumferential arc coupling outside the welding wire 7. This significantly improves the arc's encirclement of the welding wire 7 and the uniformity of heat input. Compared to single TIG electrodes or asymmetrically arranged composite arcs, this structure has a higher degree of coupling and a more symmetrical heat field distribution, completely eliminating the direction dependence of the welding process and improving process adaptability.

[0058] The annular laser beam 17 is coupled with four TIG arcs, which helps to improve the stability of the coupled arc 1, expand the heat source's effective volume, increase the overall energy input, and significantly improve the melting efficiency and energy utilization of the welding wire 7. The four tungsten electrodes are circumferentially uniformly distributed around the welding wire 7 and the annular laser beam 17, and the resulting coupled arc 1 achieves full-circumferential coupling outside the annular laser beam 17. The degree of coupling is significantly better than that of single tungsten electrode composite welding, and the directionality of welding is eliminated, thus improving the flexibility of additive welding.

[0059] The MIG welding system includes a MIG power supply 14, a wire feeder 16, a MIG welding torch, and a shielding gas supply system. These components work together via electrical and mechanical connections. The positive terminal of the MIG power supply 14 is connected to the welding wire 7, and the negative terminal is connected to a bypass shunt coordinator 9, providing the system with the main current I. Z This forms the main MIG arc. The wire feeder 16 delivers the welding wire 7 to the MIG welding torch at a set speed, allowing it to pass vertically through the center of the hollow annular laser beam 17 into the molten pool area. The MIG welding torch is responsible for guiding the welding wire 7, conducting current, and stabilizing the arc's position. The shielding gas supply system is coaxially or diaxially connected to the welding torch, continuously supplying inert gas to the welding area to form an effective gas curtain that protects the molten pool from oxidation.

[0060] The welding wire 7 passes through the interior of the annular laser beam 17, igniting an arc on the substrate 8 to form a MIG arc. This MIG arc couples with the annular laser beam 17, TIG arc 101, TIG arc 2 102, TIG arc 3 103, and TIG arc 4 104 to form a coupled arc 1. The volume and energy of the coupled arc 1 are significantly increased, which helps improve welding stability, enhances the cladding efficiency of the welding wire 7, and reduces welding spatter.

[0061] The presence of the bypass TIG arc can also preheat the welding wire 7, thereby improving the melting efficiency of the welding wire 7.

[0062] The bypass shunt coordinated control system includes multiple shunt control modules, which can adjust the main current I according to process requirements. Z Distribute the bypass current to achieve I P1 Bypass current I P2 Bypass current three I P3 Bypass current four I P4 and substrate current I MEffective control. The shunt control module includes a coordinating controller 9. Main current I Z A portion of the current emitted from MIG power supply 14 flows to substrate 8 to form substrate current I. M A portion flows to the four TIG welding torches to form a bypass current -I P1 Bypass current I P2 Bypass current three I P3 and bypass current fourI P4 Main circuit current I Z By using welding wire 7, welding wire 7 becomes a consumable electrode for welding, and its melting efficiency is significantly improved.

[0063] The current flowing through the TIG welding torch is a bypass current shunted from the main MIG current. The bypass TIG arc and the main welding wire 7 achieve strong electromagnetic coupling through a shared current loop, significantly enhancing the synergistic effect of the multi-arc system. At the same time, since part of the current is shunted through the TIG path, the main current flowing through the substrate 8 is reduced accordingly, thereby effectively reducing the heat input to the substrate 8 and reducing the heat-affected zone, which is beneficial for welding and additive manufacturing of thin-walled or heat-sensitive structures.

[0064] The bypass shunt coordination control system is connected to the TIG welding system and the MIG welding system respectively. The bypass shunt coordination control system can divert the main current of the MIG welding system to the TIG welding system, and achieve flexible switching between straight and curved welds by adjusting the bypass current value flowing into the TIG welding system.

[0065] In this invention, the welding current has the following relationship:

[0066] I Z =I P1 +I P2 +I P3 +I P4 +I M

[0067] Among them: I Z Main circuit current, I P1 For bypass current one, I P2 For the bypass current two, I P3 For the bypass current three, I P4 For bypass current four, I M The substrate current.

[0068] During the welding process, the main current I flowing from MIG power supply 14 Z A portion flows to substrate 8, forming substrate current I. MThis forms the main MIG arc; a portion flows to tungsten electrode 1 (201), tungsten electrode 2 (301), tungsten electrode 3 (401), and tungsten electrode 4 (501), forming four bypass TIG arcs: TIG arc 1 (101), TIG arc 2 (102), TIG arc 3 (103), and TIG arc 4 (104). This results in the substrate current I flowing through the substrate 8. M Diverted by the bypass, in the main circuit current I Z At a certain time, the substrate current I flowing through substrate 8 M Reducing the heat input to the substrate 8 can decrease the heat input of the substrate 8. The substrate current I can be controlled via the coordination controller 9. M By controlling the size, the heat input of the substrate 8 is reduced, allowing more energy to be applied to the welding wire 7, thereby improving energy utilization and the melting efficiency of the welding wire 7.

[0069] Bypass current I P1 I P2 I P3 I P4 It can be set to be the same or different to achieve additive or welding of straight and curved welds.

[0070] When the bypass current I P1 I P2 I P3 I P4 When the current values ​​of the four bypass TIG arcs (TIG arc 101, TIG arc 202, TIG arc 303, and TIG arc 404) are equal, their arc pressure, shape, and arc force are consistent, forming a uniform and stable coupled arc 1.

[0071] Under the action of this symmetrical electric arc field, the molten droplet 6 generated by the welding wire 7 is subjected to mutually canceling lateral arc forces from four directions (front, back, left, and right) during its descent, bearing only the resultant force of the vertical downward force. This characteristic effectively eliminates the influence of welding directionality, promotes a smooth axial transition of the molten droplet 6, and significantly improves the transition efficiency of the molten droplet 6. This process is suitable for additive manufacturing or conventional welding of straight welds, and is conducive to achieving high-quality and high-stability forming.

[0072] When the bypass current I P1 I P2 I P3 I P4When the current values ​​of the four bypass TIG arcs (TIG arc 101, TIG arc 202, TIG arc 303, and TIG arc 404) are unequal, the arc pressure, shape, and arc force differ, resulting in a non-uniform distribution of the coupled arc 1. On the side with the larger current, the arc intensity is higher and the energy density is more concentrated. During its descent, the molten droplet 6 generated by the welding wire 7 is subjected not only to the vertically downward arc force but also to a lateral deflection force pointing towards the stronger arc due to the asymmetry of the arc forces around it.

[0073] By adjusting the bypass current I P1 I P2 I P3 I P4 The relative magnitude of the force allows for precise control of the direction and amplitude of the deflection force, thereby regulating the trajectory and landing position of the molten droplet 6 and actively guiding the weld bead formation position. This mode is suitable for additive manufacturing or welding processes of curved welds, exhibiting good path adaptability and forming controllability.

[0074] By independently adjusting the bypass current of each TIG welding torch, the asymmetry of the electromagnetic force distribution around the molten droplet 6 can be dynamically controlled, thereby applying a controllable deflection force and achieving precise control of the transition direction and landing position of the molten droplet 6. This function makes the weld bead formation position programmable, and is particularly suitable for high-precision additive manufacturing and repair operations of curved welds, variable curvature paths, and three-dimensional spatial structures.

[0075] Example 2

[0076] A method for welding titanium alloys with multiple heat sources coupled together, comprising the following steps:

[0077] S1, Surface pretreatment of substrate 8.

[0078] Thoroughly clean the titanium alloy substrate 8:

[0079] First, pickling is used to remove surface oil and impurities; then, a hard grinding head is used to mechanically grind the area to be welded to remove the dense oxide layer until a uniform and bright metal body is exposed; finally, the additive area and its surrounding area of ​​at least 20mm are wiped with high-purity alcohol or acetone to ensure that there are no residual contaminants and to prevent porosity or inclusion defects from occurring during the welding process.

[0080] S2, Installation and startup of the ring laser system.

[0081] Install a ring-shaped laser generating system and connect the fiber optic transmission channel between the laser 15 and the laser mirror group 18.

[0082] After the system is started, the laser beam is controlled by multiple sets of precision reflective / refractive lenses to form a high-frequency pulsed hollow ring laser beam 17 in space.

[0083] Adjust the working distance to focus the annular laser beam 17 into an annular spot of the desired size.

[0084] According to the welding process requirements, key parameters are precisely set, including working distance, outer diameter of the annular spot, laser power and pulse frequency, to ensure uniform energy distribution and symmetrical effect around the welding wire.

[0085] S3, MIG welding system installation and startup.

[0086] To install the MIG welding system, connect the positive terminal of the MIG power supply 14 to the welding wire 7 and the negative terminal to the coordinator 9 to form the main circuit loop.

[0087] Start the wire feeder 16 to deliver the welding wire 7 to the welding area at a constant speed;

[0088] Under voltage, the main MIG arc is ignited between the welding wire 7 and the substrate 8, achieving melting and filling.

[0089] The welding wire 7 passes through the center of the annular laser beam 17, and the laser energy heats the welding wire 7 uniformly around the circumference, significantly improving the thermal field symmetry and welding accuracy; the laser preheating effect effectively promotes the refinement and stable transition of the molten droplets 6, reduces spatter, and improves the forming quality.

[0090] S4, TIG welding system installation and startup.

[0091] Four independent TIG power supplies are configured. The positive terminal of each power supply is connected to the coordinating controller 9, and the negative terminal is connected to the tungsten electrode of its corresponding TIG welding torch.

[0092] The TIG current path is: positive electrode → coordinator 9 → MIG power supply 14 → welding wire 7 → substrate 8 → tungsten electrode → negative electrode.

[0093] A bypass current conduction mechanism is formed, in which the TIG tungsten electrode acts as the current outlet, does not directly participate in the formation of the molten pool, and only undertakes part of the current diversion function.

[0094] This design can reduce the total current density through the substrate 8, reduce the concentration of heat input, avoid local overheating, and help control the microstructure evolution of the heat-affected zone.

[0095] S5, installation and startup of bypass diversion coordination control system.

[0096] Start the bypass shunt coordination control system to integrate the dynamic matching of MIG main current and multiple TIG bypass currents.

[0097] Based on specific welding process requirements (such as plate thickness, joint type, material type, etc.), set the target shunt current value for each TIG branch.

[0098] The system monitors and adjusts the current distribution ratio in real time to ensure the stability of thermo-electric coupling under the synergistic effect of multiple heat sources, thereby improving the controllability and repeatability of the welding process.

[0099] Bypass current I P1 I P2 I P3 I P4 When they are equal, the following conditions must be met:

[0100] I P1 =I P2 =I P3 =I P4 =0.25×D×T×I Z / (15+18.6T)

[0101] Bypass current I P1 I P2 I P3 I P4 When they are unequal, the landing point of the molten droplet 6 and the position of the weld bead formation can be controlled. The molten droplet 6 is positioned along I... P1 -I P3 Taking directional deflection as an example, we have:

[0102] I P1 =0.25×(1-L / 3.2)×D×T×I Z / (15+18.6T)

[0103] I P3 =0.25×(1+L / 3.2)×D×T×I Z / (15+18.6T)

[0104] I P2 =I P4 =0.25×D×T×I Z / (15+18.6T)

[0105] Among them, the main circuit current I Z The preferred values ​​are 160~280A; D is the width of the weld bead to be welded, preferably 5~12mm; T is the weld penetration depth, preferably 0.5~1mm; L is the droplet offset distance, preferably 0~2mm.

[0106] TIG arc 101, TIG arc 2 102, TIG arc 3 103, TIG arc 4 104, the main MIG arc, and the ring laser beam 17 together form a coupling arc 1, realizing multiple thermal field coupling modes such as TIG-MIG arc coupling and laser-arc coupling.

[0107] During the welding process, all systems work closely together to ultimately achieve the desired additive weld bead formation.

[0108] It should be noted that all terms used in this invention to indicate direction and position, such as "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "inner", "outer", "top", "lower", "tail end", "head end", "center", etc., are only used to explain the relative positional relationship and connection between components in a specific state. They are only for the convenience of describing this invention and do not require that this invention must be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0109] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0110] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A titanium alloy welding device with multiple heat source coupling, characterized in that, The welding apparatus includes a ring laser system, a TIG welding system, a MIG welding system, and a bypass shunt coordination control system, forming arc coupling between TIG and MIG and optical arc coupling between laser and arc. The bypass shunt coordination control system is connected to the TIG welding system and the MIG welding system respectively. The bypass shunt coordination control system can divert the main current of the MIG welding system to the TIG welding system, and can achieve flexible switching between straight and curved welds by adjusting the bypass current value flowing into the TIG welding system. The ring laser system forms a ring laser beam (17). The TIG welding system includes four TIG welding torches, which hold four tungsten electrodes. The four tungsten electrodes are circumferentially uniformly distributed around the ring laser beam (17) to improve the stability of the coupled arc and increase the cladding efficiency. The bypass shunt coordination control system includes a shunt control module, which is used to control the main current I. Z The distribution and bypass current are controlled to flexibly switch between straight and curved weld seams; the main current I... Z The use of welding wire significantly improves melting efficiency.

2. The welding apparatus according to claim 1, characterized in that, The welding wire of the MIG welding system passes through the interior of the annular laser beam (17), achieving uniform circumferential heating of the welding wire.

3. The welding apparatus according to claim 2, characterized in that, The annular laser beam (17) is a high-frequency pulsed laser, and the annular spot of the annular laser beam (17) is stably applied to the neck of the molten droplet.

4. The welding apparatus according to claim 1, characterized in that, The current relationship of the welding device is: I Z =I P1 +I P2 +I P3 +I P4 +I M , among which, I P1 For bypass current I, P2 For bypass current II, I P3 For bypass current three, I P4 For bypass current four, I M The substrate current; the bypass current I P1 Bypass current I P2 Bypass current three I P3 and bypass current fourI P4 The current flows to the four tungsten electrodes respectively, forming four TIG arcs; the substrate current I M The current flows to the substrate (8) to form the main MIG arc.

5. The welding apparatus according to claim 4, characterized in that, For straight welds, I P1 I P2 I P3 I P4 Set to equal; for curved welds, I P1 I P2 I P3 I P4 Set them to be unequal.

6. A method for welding titanium alloys using multiple heat source coupling, characterized in that, Welding is performed using the welding apparatus described in any one of claims 1 to 5, and the method includes the following steps: S1, Pretreatment of substrate (8) surface; S2, Installation and startup of the ring laser system; S3, MIG welding system installation and startup; S4, TIG welding system installation and startup; S5, installation and startup of bypass diversion coordination control system.

7. The welding method according to claim 6, characterized in that, Step S2 includes: S21, Install a ring laser system and connect to the fiber optic transmission channel; S22, activate the ring laser system to form a ring laser beam (17). S23, adjust the working distance so that the annular laser beam (17) is focused into an annular spot of the required size.

8. The welding method according to claim 6, characterized in that, Step S3 includes: S31, install the MIG welding system, connect the welding wire 7 and the bypass shunt coordination control system to form the main circuit loop; S32, start the wire feeder (16).

9. The welding method according to claim 6, characterized in that, Step S4 includes: connecting the TIG welding torch and the bypass shunt coordination control system.

10. The welding method according to claim 6, characterized in that, Step S5 includes: S51, start the bypass shunt coordination control system to achieve dynamic matching between main current and bypass current; S52, set the target shunt current value for each TIG branch; S53 monitors and adjusts the current distribution ratio in real time.

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