Multi-energy field composite welding method and device for enhancing penetration of super-thick plate

Abstract

The application provides a multi-energy field composite welding method and device for enhancing the penetration of super-thick plates. The method comprises the following steps: using a laser heat source to construct a plasma environment in a Y-shaped groove structure, which is arranged at the butt joint of two plates to be welded; using the laser heat source and the plasma environment to act on an arc heat source together, so that the arc heat source forms a long arc, thereby enabling the long arc to reach at least the bottom of the Y-shaped groove structure. The method induces a long arc by the combined action of the laser heat source and the plasma environment, enables the long arc to act on the bottom of the Y-shaped groove structure in depth, realizes single-sided welding and double-sided forming, effectively solves the defects of difficult welding groove penetration and difficult root penetration of super-thick plate butt joints existing in traditional arc welding and laser arc welding, realizes deep welding groove penetration, strong penetration capacity, low filling capacity, small weld deformation and other advantages, and effectively improves the welding stability.

Description

Technical Field

[0001] This invention relates to the field of welding, and provides a multi-energy field composite welding method and apparatus for achieving enhanced penetration of ultra-thick plates using laser-arc composite welding. Background Technology

[0002] Laser-arc hybrid welding is a novel welding method that combines the advantages of laser welding and arc welding. It utilizes both a laser and an electric arc as dual heat sources, acting simultaneously on the same molten pool. The laser beam guides and stabilizes the arc, while the arc increases the metal's absorption of the laser, enhancing the bridging ability of the molten droplet transfer. This method fully leverages the advantages of both laser welding and arc welding while compensating for their respective shortcomings.

[0003] However, when laser-arc hybrid welding is applied to welding ultra-thick plates (over 20mm thick), it commonly suffers from defects such as excessively large weld bevels, difficulty in penetration at the bevel, excessive weld filler, and excessive deformation at the joint. For example, many critical load-bearing components on the car body of rail transit vehicles, such as coupler mounting seats, play a crucial role in the coupling and traction of train cars and typically bear high alternating and impact loads. These critical load-bearing components are usually made of ultra-thick aluminum alloy plates exceeding 20mm in thickness. If arc welding is used alone, it is prone to problems such as a large number of weld passes, low product qualification rate, large welding deformation, and high residual stress. If the aforementioned laser-arc hybrid welding is used, the root penetration at the joint of ultra-thick plates is still difficult, weld porosity is difficult to overflow, and some of the problems mentioned above with laser hybrid welding still exist. Summary of the Invention

[0004] This invention provides a multi-energy field composite welding method to enhance the penetration of ultra-thick plates. It can solve the defects of traditional arc welding and laser arc welding, such as difficulty in penetration of the weld groove and difficulty in root penetration at the joint of ultra-thick plates. It achieves advantages such as deep weld groove penetration, strong penetration ability, low filler content, and small weld deformation, effectively improving welding stability.

[0005] The present invention also provides a multi-energy field composite welding device for enhancing the penetration of ultra-thick plates.

[0006] The present invention provides a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates, comprising the following steps.

[0007] A plasma environment is created in a Y-shaped bevel structure using a laser heat source, the Y-shaped bevel structure being set at the joint of two plates to be welded.

[0008] The laser heat source and the plasma environment work together to form a long electric arc, so that the long electric arc can reach at least the bottom of the Y-shaped bevel structure.

[0009] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the step of constructing a plasma environment in the Y-shaped groove structure using a laser heat source further includes the following steps.

[0010] Laser-assisted composite welding is used to weld along the length of the Y-shaped groove structure. The laser-assisted composite welding includes a laser heat source and an electric arc heat source, with the laser heat source located in front of the electric arc heat source.

[0011] The laser beam action section of the laser heat source at least covers the docking portion of the Y-shaped bevel structure, so that the docking portion forms the plasma environment.

[0012] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the step of the laser beam action section of the laser heat source at least covering the butt joint of the Y-shaped groove structure to form the plasma environment at the butt joint further includes: the laser beam action section acting at least on the top of the butt joint to melt the base material at the top of the butt joint; a portion of the melted base material flows to the bottom of the butt joint, and another portion is heated and vaporized to form plasma, the plasma being located in the gap of the butt joint to construct the plasma environment in the gap of the butt joint.

[0013] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the step of utilizing the laser heat source and the plasma environment to act on the electric arc heat source to form a long electric arc, so that the long electric arc can at least reach the bottom of the Y-shaped groove structure, further includes the following steps.

[0014] The electric arc heat source acts on the joint of the Y-shaped bevel structure and forms a conventional electric arc.

[0015] Based on the suppressive effect of the laser heat source and the guiding effect of the plasma environment, the conventional electric arc is induced and transformed into the long electric arc.

[0016] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the stiffness of the long arc is greater than that of the conventional arc, and the arc length of the long arc is greater than that of the conventional arc.

[0017] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates further includes the following steps.

[0018] The electric arc information at the bottom of the Y-shaped bevel structure is collected and monitored in real time.

[0019] Based on the arc information, the arc voltage of the arc heat source is adjusted online.

[0020] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the step of adjusting the arc voltage of the arc heat source online based on the arc information further includes the following.

[0021] The arc information includes the arc signal and the arc length.

[0022] If the arc signal can be collected at the bottom of the Y-shaped bevel structure, it is further determined whether the arc length exceeds the bottom of the Y-shaped bevel structure. If so, the current arc voltage is reduced; otherwise, the arc voltage is kept unchanged.

[0023] If the arc signal is not detected at the bottom of the Y-shaped bevel structure, the current arc voltage is increased until the arc signal can be detected at the bottom of the Y-shaped bevel structure.

[0024] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the Y-shaped groove structure includes a butt joint and a groove joint.

[0025] The mating part is vertically arranged and formed between the mating end faces of the two plates, and a gap is formed between the mating end faces of the two plates at the position of the mating part.

[0026] The bevel portion is connected to the mating portion and is located near the welding surface of the mating portion.

[0027] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the bevel portion includes a ramp and a bottom, the ramp and the bottom being sequentially connected between the welding surface and the butt joint.

[0028] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the ramp is inclined downward relative to the surface of the plate; and the ramps on the two plates tend to gradually approach each other from the welding surface to the butt joint.

[0029] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the bottom of the slope is an arc-shaped slope, and the slope of the bottom of the slope is less than or equal to the slope of the ramp.

[0030] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the two plates include a first plate and a second plate, the end face of the first plate and the end face of the second plate are abutted and form a gap; the butt joint includes a plurality of protruding joints, all of which are located within the gap.

[0031] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the butt joint includes at least two said convex joints, all of which are fixed to the end face of the first plate and can contact the end face of the second plate.

[0032] According to a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to the present invention, the adjacent convex joints are arranged at intervals.

[0033] According to the present invention, a multi-energy field composite welding method for enhancing the penetration of ultra-thick plates is provided, wherein the thickness of both plates is greater than or equal to 20 mm.

[0034] The present invention also provides a multi-energy field composite welding device for enhancing the penetration of ultra-thick plates, which can perform the above-mentioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates; the multi-energy field composite welding device for enhancing the penetration of ultra-thick plates includes an arc module, a laser module and a drive module.

[0035] The electric arc module forms an electric arc heat source.

[0036] The laser module has a laser heat source, which is used to construct a plasma environment in the Y-shaped bevel structure. The laser heat source and the plasma environment work together to form a long electric arc, so that the long electric arc can reach at least the bottom of the Y-shaped bevel structure.

[0037] A drive module, connected to the laser module and the arc module, is used to drive the laser heat source and the arc heat source to weld along the Y-shaped groove structure.

[0038] According to the present invention, a multi-energy field composite welding device for enhancing the penetration of ultra-thick plates further includes: a welding monitoring module, which is connected to the laser module and the arc module, for real-time acquisition and monitoring of the arc information at the bottom of the Y-shaped bevel structure, and for online adjustment of the arc voltage of the arc heat source based on the arc information.

[0039] The multi-energy field composite welding method for enhancing the penetration of ultra-thick plates proposed in this invention includes the following steps: constructing a plasma environment in a Y-shaped groove structure using a laser heat source, wherein the Y-shaped groove structure is set at the joint of two plates to be welded; utilizing the combined action of the laser heat source and the plasma environment on the electric arc heat source to form a long electric arc, thereby ensuring that the long electric arc can reach at least the bottom of the Y-shaped groove structure. This method utilizes the laser heat source to construct a plasma environment in the Y-shaped groove structure, thereby creating an environment conducive to inducing a long electric arc, and achieving the positioning and jointing of ultra-thick plates through the Y-shaped groove structure, effectively resisting deformation during welding, avoiding welding shrinkage, and ensuring the stability of the joint between the two plates during welding; the combined action of the laser heat source and the plasma environment induces a long electric arc, allowing the long electric arc to deeply penetrate to the bottom of the Y-shaped groove structure, achieving single-sided welding with double-sided forming.

[0040] Compared with traditional laser arc welding, this method can solve the engineering problems existing in ultra-thick plate welding, and effectively solve the defects of traditional arc welding and laser arc welding, such as difficult weld groove penetration and difficult root penetration at the joint of ultra-thick plates. It enhances the welding stability of ultra-thick plates and the root penetration ability of welds, and achieves advantages such as deep weld groove penetration, strong penetration ability, low filling amount, and small weld deformation, thus effectively improving welding stability.

[0041] The multi-energy field composite welding device for enhancing the penetration of ultra-thick plates proposed in this invention includes: an arc module, a laser module, and a drive module. The arc module forms an arc heat source. The laser module forms a laser heat source. The drive module connects the laser module and the arc module, and is used to drive the laser heat source and the arc heat source to weld along a Y-shaped groove structure, thereby utilizing the arc module and the laser module to jointly execute the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates. This welding device, by executing the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates, possesses all the advantages of the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates, which will not be elaborated further here. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0043] Figure 1 This is a schematic flowchart of the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by the present invention.

[0044] Figure 2 This is a schematic diagram showing some types and evolution of the Y-shaped bevel structure provided by the present invention.

[0045] Figure 3 This is a schematic diagram of the basic structure of the Y-shaped bevel structure provided by the present invention.

[0046] Figure 4 This is a schematic diagram of the Y-shaped bevel structure provided by the present invention.

[0047] Figure 5 This is a front sectional view of the Y-shaped bevel structure provided by the present invention.

[0048] Figure 6 This is a top view of the Y-shaped bevel structure provided by the present invention.

[0049] Figure 7 This is a schematic diagram of the structure of the first plate provided by the present invention.

[0050] Figure 8 This is a schematic diagram of the structure of the second plate provided by the present invention.

[0051] Figure 9 This is a cross-sectional view of the joint of the Y-shaped bevel structure provided by the present invention.

[0052] Figure 10 This is a stress analysis diagram of the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by the present invention.

[0053] Figure 11 This is a schematic diagram of the layout of the laser heat source and the electric arc heat source in the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by the present invention.

[0054] Figure 12 and Figure 13 This is a schematic diagram illustrating the position and principle of the laser heat source acting on the Y-shaped groove structure in the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by the present invention.

[0055] Figure 14 and Figure 15 This is a schematic diagram illustrating the principle of the long arc induction process in the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by the present invention.

[0056] Figure 16 This is a high-speed photograph of the long arc induction process in the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by the present invention.

[0057] Figure 17 This is a schematic diagram of the process for maintaining and dynamically adjusting the long electric arc in the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by the present invention.

[0058] Figure 18 This is a schematic diagram illustrating the logic principle of long arc maintenance and dynamic adjustment in the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by this invention.

[0059] Figure 19 This is a schematic diagram showing the specific dimensions of the Y-shaped bevel structure in a specific embodiment of the present invention.

[0060] Figure 20 , Figure 21 , Figure 22 and Figure 23 This is a high-speed photographic image of the long arc induction and maintenance in the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates provided by the present invention.

[0061] Figure 24 This is a schematic diagram of the weld bead arrangement in a weldment obtained by using a multi-energy field composite welding method to enhance the penetration of ultra-thick plates in a specific embodiment of the present invention.

[0062] Figure 25 This is a macroscopic metallographic image of the weld bead in a weldment obtained by using a multi-energy field composite welding method to enhance the penetration of ultra-thick plates in a specific embodiment of the present invention.

[0063] Figure 26 This is a schematic diagram of the weld bead arrangement in a weldment obtained by conventional electric arc welding method in a comparative example provided by the present invention.

[0064] Figure 27 This is a macroscopic metallographic image of the weld bead in a weldment obtained by conventional electric arc welding method in a comparative example provided by the present invention.

[0065] Figure label: 1. Bevel; 11. Ramp; 12. Bottom of slope; 2. Butt joint; 3. convex joint; 4. First plate; 5. Second plate; 6. Molten droplet; 7. Arc heat source; 71. Long arc; 8. Laser heat source; 81. Laser beam emission section; 82. Laser beam focal point; 83. Laser beam action section; 9. Charge. Detailed Implementation

[0066] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0067] Reference Figures 1 to 25 As shown, the present invention will elaborate in detail on the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates (the present invention may be referred to as the "method") and the multi-energy field composite welding apparatus for enhancing the penetration of ultra-thick plates capable of performing the method (the present invention may be referred to as the "welding apparatus") through the following embodiments.

[0068] like Figure 1 As shown, the multi-energy field composite welding method for enhancing the penetration of ultra-thick plates proposed in this invention includes the following steps.

[0069] Step 1: Construct a plasma environment in the Y-shaped bevel structure using laser heat source 8, wherein the Y-shaped bevel structure is set at the joint of two plates to be welded.

[0070] Step 2: The laser heat source 8 and the plasma environment work together to form a long electric arc 71, so that the long electric arc 71 can reach at least the bottom of the Y-shaped bevel structure.

[0071] The method described in this embodiment of the invention utilizes a laser heat source 8 to construct a plasma environment within a Y-shaped bevel structure, thereby creating an environment conducive to inducing a long electric arc 71. By setting up the Y-shaped bevel structure, the positioning and docking of ultra-thick plates are achieved, effectively resisting deformation during the welding process, avoiding welding shrinkage, and ensuring the stability of the joint between the two plates during the welding process. The long electric arc 71 is induced by the combined action of the laser heat source 8 and the plasma environment, allowing the long electric arc 71 to deeply act on the bottom of the Y-shaped bevel structure, achieving single-sided welding and double-sided forming.

[0072] It should be noted that ultra-thick plates refer to plates with a thickness greater than or equal to 20 mm. Therefore, the thickness of the plates to be welded in the embodiments of the present invention is greater than or equal to 20 mm. Preferably, the plates to be welded in the embodiments of the present invention are aluminum alloy plates with a thickness greater than or equal to 20 mm, which can typically be applied to the car body and coupler mounting positions of rail vehicles.

[0073] In some embodiments, in order to achieve high penetration, small filler and low heat input in the welding of ultra-thick plates, the method adopts a high energy density laser-arc hybrid welding method, and the following analysis is made based on the characteristics of the welding heat source of laser-arc hybrid welding.

[0074] Laser-arc hybrid welding utilizes a laser heat source 8 and an electric arc heat source 7 as dual heat sources, acting simultaneously on the same molten pool. The laser guides and stabilizes the arc, while the arc enhances the metal's absorption of the laser, thereby strengthening the bridging ability of the molten droplets 6. The laser beam generated by the laser heat source 8 features high energy density and rapid heating, while the electric arc provides a large heat-affected zone and a stable welding process. This dual heat source effect enables laser-arc hybrid welding to simultaneously achieve high penetration depth and a wide molten pool, thus improving welding quality and efficiency.

[0075] Laser-arc hybrid welding enables highly efficient energy utilization. The high energy density and rapid heating characteristics of the laser beam cause the metal in the molten pool to melt rapidly and form a keyhole, while the electric arc fills the molten pool and keyhole, achieving sufficient heating and penetration of the molten pool. This highly efficient energy utilization characteristic makes laser-arc hybrid welding a significant advantage in welding thick plates and materials with large thicknesses.

[0076] Based on this, the method of this invention sets a Y-shaped bevel structure at the butt joint position of the ultra-thick plate, thereby achieving reliable positioning of the assembly gap during the welding process, effectively resisting welding deformation, and establishing a reliable foundation for creating a stable long electric arc 71 induced environment.

[0077] In some embodiments, such as Figure 2 and Figure 3 As shown, the Y-shaped bevel structure of this embodiment includes a butt joint 2 and a bevel joint 1. The bevel joint 1 is connected to the butt joint 2 and is located near the welding surface of the butt joint 2. In this embodiment, the surfaces of the two plates near the laser heat source 8 and the arc heat source 7 are the front surfaces of the plates, i.e., the upper surfaces of the plates, i.e., the welding surfaces mentioned above; while the surfaces away from the laser heat source 8 and the arc heat source 7 are the back surfaces of the plates, i.e., the lower surfaces of the plates. The butt joint 2 is vertically arranged and formed between the end faces (i.e., blunt edges) of the two plates where they are joined.

[0078] In some embodiments, the selection and deformation reference of the Y-shaped bevel structure Figure 2 As shown. The Y-shaped bevel structure is preferably set at the joint of the two plates to give full play to the advantages of the dual heat sources of laser heat source 8 and electric arc heat source 7. Figure 2 The groove A shown is the basic structure of a Y-shaped groove. Groove A has a large groove angle and a large filler volume. Due to the low penetration of arc welding, the blunt edge size is small. Since laser hybrid welding has a stronger penetration than arc welding, to avoid the butt joint 2 being too easily penetrated and having excessive heat input, which would affect the welding quality, a groove structure with a larger blunt edge than groove A can be selected. (Refer to...) Figure 2 The bevel B is shown. Furthermore, based on the concentrated arc density in laser-coupled welding, a bevel structure with a smaller bevel angle is selected, referring to... Figure 2 The bevel C is shown. Furthermore, since the root of the connection between the bevel portion 1 and the butt joint 2 of bevel C is relatively sharp, a platform is added at the root position of bevel C to reduce root welding defects, as shown in the reference. Figure 2 The bevel D is shown. Furthermore, the connection between the platform at the root of bevel D and the inclined ramp 11 of bevel D still has a sharp point, which easily leads to incomplete fusion defects. To improve this defect, the connection between the inclined ramp 11 and the platform at the root of the bevel is optimized into an arc-shaped slope structure, thereby transforming the bevel portion 1 into an approximately U-shaped bevel structure. (Refer to...) Figure 2 The bevel E shown is the most preferred Y-shaped bevel structure selected in the method described in the embodiments of the present invention, taking all factors into consideration.

[0079] In some embodiments, to facilitate accurate self-positioning of the assembly gap between the two plates before welding, such as... Figure 4As shown, preferably, a gap is formed at the joint 2 of the two plates at their mating end faces. This gap not only ensures accurate assembly and welding positioning but also provides reliable space for the induction of the long electric arc 71, allowing it to penetrate the gap in the joint 2 and reach the bottom of the weldment, achieving single-sided welding with double-sided forming. Specifically, as shown... Figures 4 to 6 As shown, the two plates include a first plate 4 and a second plate 5. The end face of the first plate 4 and the end face of the second plate 5 are in contact to form the aforementioned gap.

[0080] In some specific embodiments, such as Figure 3 As shown, the bevel portion 1 of the Y-shaped bevel structure includes a ramp 11 and a bevel base 12, which are sequentially connected between the welding surface and the butt joint 2. To facilitate the guidance and accuracy of the heat input from the laser heat source 8 and the arc heat source 7, the ramp 11 is preferably inclined downwards relative to the surface of the plate; furthermore, the ramps 11 on both plates gradually approach each other from the welding surface towards the butt joint 2. This arrangement also ensures that the heat input energy is more concentrated at the root of the bevel portion 1, thereby achieving sufficient weld penetration with a smaller heat input. Moreover, this arrangement allows for better stress distribution in the weld when under load, thereby improving the strength of the welded joint and making it more advantageous for butt welding of ultra-thick plates to withstand greater loads, thus improving the structural strength and stability of the weld.

[0081] In some specific embodiments, such as Figure 3 and Figure 4 As shown, the preferred bevel portion 1 has an arc-shaped bottom 12, and the slope of the bottom 12 is less than or equal to the slope of the ramp 11. This configuration ensures that, for the same weldment thickness, less weld metal is required compared to other types of bevel structures, which helps to reduce the use of welding materials and lower welding costs. Furthermore, under the same welding conditions, relatively less welding heat can be used, resulting in less weld deformation, making it easier to penetrate the root and thus improving welding quality. In addition, this configuration also allows the Y-shaped bevel structure to better distribute stress when under load, thereby maintaining high-precision welding and ensuring better dimensional stability of the weldment.

[0082] In some embodiments, such as Figures 4 to 6 As shown, the preferred mating part 2 includes several protruding joints 3, all of which are located within the gap. This arrangement enables self-positioning and deformation resistance of the blunt edge of the ultra-thick plate butt joint. Furthermore, by providing the protruding joints 3, it ensures that the plates can contact each other to eliminate assembly gaps, effectively resists structural deformation during welding, avoids welding shrinkage, and thus ensures the stability of the gap during welding.

[0083] In some specific embodiments, such as Figure 5 and Figure 6 As shown, the mating part 2 includes at least two male connectors 3. All male connectors 3 are fixed to the end face of the first plate 4 and can contact the end face of the second plate 5. This structural arrangement causes the first plate 4 to form as shown in the diagram. Figure 7 The structure shown has the second plate 5 formed as follows: Figure 8 The structure shown is such that by simply having the first plate 4 and the second plate 5 in contact through the protruding joint 3, a structural positioning contact can be achieved without requiring additional positional adjustments to the gap. This facilitates assembly and ensures that there is sufficient space between the two plates to induce a long electric arc 71.

[0084] In some specific embodiments, adjacent protruding joints 3 are spaced apart to provide a sufficiently large plasma environment for inducing a long electric arc 71. For example Figure 6 As shown, two protruding joints 3 are arranged at intervals on the mating end face of the first plate 4. The two-line positioning contact surface can ensure reliable and stable end face contact assembly of the first plate 4 and the second plate 5, ensure assembly gap, and leave plasma environment for long electric arc 71 to be induced between the two protruding joints 3 and on both sides, thereby achieving welding stability and improving welding quality.

[0085] It should be noted that in the method described in this embodiment of the invention, the two plates to be welded can be pre-assembled and butt-jointed to achieve joint assembly. During the joint assembly process, a first plate 4 and a second plate 5 are selected for assembly and butt-jointing to form a Y-shaped bevel structure. Figure 7 The first plate 4 shown is self-positioned by the fixed protrusion joint 3 at the mating end face, while... Figure 8 The second plate 5 shown has a smooth mating end face, facilitating direct contact and connection with the protruding joint 3 of the first plate 4. Because the first plate 4 has a protruding joint 3 of fixed height on its mating end face, it not only achieves self-positioning during assembly between the two plates, but also, since the protrusion height of the protruding joint 3 directly determines the gap width formed by the mating part 2, it ensures uniform gaps during the assembly of the plates to be welded and effectively resists structural shrinkage during welding. That is, as shown... Figure 9 As shown, the gap width D of the mating portion 2 formed between the first plate 4 and the second plate 5 in the Y-shaped bevel structure is equal to the protrusion height d of the convex joint 3. Therefore, the first plate 4 and the second plate 5 can achieve self-positioning by contacting each other through the convex joint 3, ensuring that the gap of the joint assembly meets the process requirements, and no adjustment of the joint gap size is required.

[0086] It should be noted that in the method described in the embodiments of the present invention, the ultra-thick plate forms liquid metal due to heat during the welding process, and shrinks after solidification, thus... Figure 10As shown, as the molten droplet 6 travels, a welding shrinkage force F1 is generated on both sides of the weld. This welding shrinkage force F1 compresses the weld on both sides of the weld formed by the molten droplet 6. However, because the Y-shaped groove structure has a protruding joint 3 at the butt joint 2, the welding shrinkage force F1 compresses the protruding joint 3 at the butt joint 2, causing the protruding joint 3 to generate a reverse resistance force T1. Therefore, the resistance force T1 generated by the protruding joint 3 plays a better role in resisting welding deformation and effectively fixes the gap of the butt joint 2, ensuring the consistency of the joint gap during the welding process. Figure 10 The arrow M in the diagram indicates the welding direction.

[0087] In some specific embodiments of the Y-shaped bevel structure, at least one set of specific embodiments is given to describe the dimensions of the Y-shaped bevel structure in detail. For example... Figure 3 As shown, the height of the butt joint 2 is set as the blunt edge dimension a, and the dimensions of the bevel part 1 include the bevel opening b and the bevel depth h. Since the penetration capability of laser-arc hybrid welding determines the blunt edge dimension a of the two plates in the Y-shaped bevel structure, to achieve single-pass welding of the cover surface, the coverage area of ​​the welding arc heat source 7 determines the bevel opening b, while the net elongation of the arc heat source 7 determines the bevel depth h. The welding capability of this method applied to ultra-thick plates is the plate thickness h + a of the two plates. Using the welding process experiments corresponding to this method, the specific parameters of the Y-shaped bevel structure are obtained as shown in the table below.

[0088] Table 1. Specific parameters of the Y-shaped bevel structure

[0089] Based on the specific structure of the Y-shaped bevel structure described above, the welding method for ultra-thick plate welding of the present invention will be described in detail below.

[0090] In some embodiments, step 1 above, which involves constructing a plasma environment in the Y-shaped bevel structure using a laser heat source 8, further includes the following steps.

[0091] Step 11: Weld along the length of the Y-shaped groove structure using laser hybrid welding. The laser hybrid welding includes a laser heat source 8 and an electric arc heat source 7, with the laser heat source 8 located in front of the electric arc heat source 7.

[0092] Step 12: The laser beam action section 83 of the laser heat source 8 at least covers the docking part 2 of the Y-shaped bevel structure so that the docking part 2 forms a plasma environment.

[0093] It should be noted that, as Figure 11As shown, in order to effectively lengthen the welding arc and increase arc penetration during the welding process using the laser heat source 8, the laser heat source 8 and the arc heat source 7 are rationally arranged according to the characteristics of the laser and the arc, based on step 11. The laser heat source 8 is positioned in front of the welding direction M, and the arc heat source 7 is positioned behind the laser, so that the laser beam formed by the laser heat source 8 is always in front of the welding arc formed by the arc heat source 7. This arrangement ensures that the laser beam preferentially acts on the Y-shaped groove structure to create a plasma environment. As the welding progresses, the welding arc entering and being in the plasma environment can be influenced by the preceding laser beam to induce a long arc 71, achieving the purpose of reliably inducing the long arc 71. Preferably, the distance between the laser heat source 8 and the welding heat source is 2mm~4mm, and most preferably 3mm, to avoid the two being too close or too far apart, which would affect the induction effect of the long arc 71.

[0094] It should be noted that, as described in step 12, the laser beam formed by the laser heat source 8 includes a laser beam emitting section 81, a laser beam focal section 82, and a laser beam acting section 83. (Refer to...) Figure 12 As shown. Ensuring that the laser beam action section 83 at least covers the docking part 2 of the Y-shaped bevel structure ensures that the laser beam action section 83 can act on the entire range of the gap of the docking part 2, thereby creating a plasma environment with a sufficiently large space, which is more conducive to the stable induction of the long electric arc 71.

[0095] In some specific embodiments, step 12 above, where the laser beam action segment 83 of the laser heat source 8 at least covers the docking portion 2 of the Y-shaped bevel structure to form a plasma environment at the docking portion 2, further includes the following: the laser beam action segment 83 acts at least on the top of the docking portion to melt the base material at the top of the docking portion; a portion of the melted base material flows to the bottom of the docking portion, and another portion is heated and vaporized to form plasma, which is located in the gap of the docking portion to construct a plasma environment in the gap of the docking portion, as described above. Figure 13 As shown. This setup can reliably achieve laser coverage of the butt joint 2 of the Y-shaped bevel structure. Furthermore, by utilizing the melting process of the base material, reliable penetration is achieved through flow, improving the penetration capability. On the other hand, the heat-induced vaporization of the base material forms plasma within the gap, altering the welding environment within the gap. The movement of charges 9 within the plasma then exerts a precise, efficient, and reliable influence on the subsequent welding arc.

[0096] In some embodiments, step 2 of the method of the present invention, which involves using a laser heat source 8 and a plasma environment to act on an electric arc heat source 7 to form a long electric arc 71, so that the long electric arc 71 can at least reach the bottom of the Y-shaped bevel structure, further includes the following steps.

[0097] Step 21: The electric arc heat source 7 acts on the joint of the Y-shaped bevel structure and forms a conventional electric arc.

[0098] Step 22: Based on the suppressive effect of the laser heat source 8 and the guiding effect of the plasma environment, the conventional electric arc is induced and transformed into a long electric arc 71.

[0099] It should be noted that, as Figure 14 and Figure 15 As shown, step 21 above actually refers to the welding arc generated by the welding heat source being either a conventional arc or a long arc 71 induced by the welding heat source. During the welding process, since the arc heat source 7 is behind the laser heat source 8, that is, the welding wire used to generate the conventional arc is behind the laser beam, the welding wire and the root of the bevel 1 first form a conventional arc. The conventional arc is suppressed by the laser beam and guided by the plasma in the plasma environment within the gap of the butt joint 2, causing the stiffness and length of the welding arc to increase until it reaches the bottom of the butt joint 2, thus transforming the conventional arc into a long arc 71. As the arc length increases, the base material at the bottom of the Y-shaped bevel structure can be heated and melted, achieving stable and reliable long arc 71 deep penetration welding. The method of this embodiment records the welding arc during the welding process using a high-speed camera, obtaining the image and mechanism of the long arc 71 as follows: Figure 16 As shown.

[0100] It should be noted that, based on the above explanation of principles, the stiffness of the long electric arc 71 described in this embodiment of the invention is greater than that of a conventional electric arc. The arc length of the long electric arc 71 described in this embodiment of the invention is greater than that of a conventional electric arc.

[0101] In some embodiments, after inducing a long electric arc 71 through a reasonable process based on steps 1 and 2 described above, the method further includes a step of maintaining and dynamically adjusting the long electric arc 71. This step maintains the effect of the long electric arc 71 during the welding process through measures such as the composite laser heat source 8 and reducing sidewall attraction, thereby ensuring more stable and reliable deep penetration welding. Specifically, as shown... Figure 17 As shown, the maintenance and dynamic adjustment steps specifically include the following steps.

[0102] Step 31: Collect and monitor the electric arc information at the bottom of the Y-shaped bevel structure in real time.

[0103] Step 32: Based on the arc information, adjust the arc voltage of the arc heat source 7 online.

[0104] The steps of maintaining and dynamically adjusting the long electric arc 71 described in this embodiment of the invention, through implementing steps 31 and 32, enable real-time monitoring of the electric arc information at the bottom of the Y-shaped bevel structure (i.e., as shown in the figure). Figure 17The arc detection shown enables reliable arc information feedback (i.e., as illustrated). Figure 17 The parameter feedback processor (shown as feeding back arc information) dynamically adjusts the arc voltage of the arc heat source 7 (i.e., as shown in the figure). Figure 17 The welding parameters are adjusted as shown, thereby ensuring that the welding machine power supply can output the adjusted welding parameters (i.e., as shown) to the arc heat source 7. Figure 17 The output adjustment parameters are shown, and this process is repeated to achieve real-time dynamic adjustment. This process can maintain a stable long arc 71 welding process after the long arc 71 is generated, and ensure stable output welding process parameters, thereby obtaining a more stable welding process.

[0105] In some specific embodiments, such as Figure 18 As shown, step 32, the step of adjusting the arc voltage of the arc heat source 7 online based on arc information, further includes the following: It should be noted that the arc information includes the arc signal and the arc length.

[0106] If an arc signal can be collected at the bottom of the Y-shaped groove structure, it means that the long arc 71 has been able to penetrate to the bottom of the Y-shaped groove structure. Based on this, it is further determined whether the arc length exceeds the bottom of the Y-shaped groove structure. If so, it means that the long arc 71 is too long, and the current arc voltage should be reduced accordingly. Otherwise, it means that the parameters of the long arc 71 meet the welding requirements, and the arc voltage should be kept unchanged.

[0107] If no arc signal is detected at the bottom of the Y-shaped bevel structure, it indicates that the long arc 71 is too short. Therefore, the current arc voltage should be increased until an arc signal can be detected at the bottom of the Y-shaped bevel structure.

[0108] That is, in the method described in the embodiments of the present invention, the arc voltage is adjusted in real time by the arc signal and the arc length, thereby achieving reliable maintenance and optimization of the long arc 71.

[0109] In some specific embodiments, after completing the acquisition of the arc signal and the determination of the arc length data, the method further determines whether the arc temperature is too high. If so, the current arc voltage is reduced accordingly; otherwise, the arc voltage is kept constant. This temperature determination can effectively prevent excessive heat output from a long arc from reducing welding quality, damaging the welding environment, and affecting the welding process.

[0110] It should be noted that, in order to reliably detect the arc signal at the bottom of the Y-shaped bevel structure, it is preferable to set an arc signal receiving sensor at the bottom of the Y-shaped bevel structure. This sensor is connected to the aforementioned parameter feedback processor via a signal, the parameter feedback processor is connected to the welding machine power supply via a signal, and the welding power supply is connected to the welding device via a signal, thereby realizing reliable monitoring of the welding process and achieving the maintenance and dynamic adjustment of the long arc 71.

[0111] This invention provides a specific embodiment for butt welding of ultra-thick aluminum alloy plates with a thickness of 20mm. The ultra-thick plate is a 6005A aluminum alloy plate with a thickness of 20mm. The welding is performed using the multi-energy field composite welding method for enhancing penetration of ultra-thick plates described in this embodiment. To meet the long arc 71 induction condition, the weld bevel structure formed between the two plates of the ultra-thick plate is as follows... Figure 19 As shown in the figure, the specific dimensions are shown in Table 2.

[0112] Table 2. Specific parameters of the welding groove structure in specific embodiments

[0113] The method described in this specific embodiment is used to weld the aforementioned ultra-thick plate. Figure 20 and Figure 21 The image shows a high-speed image of a long arc 71 induced in the multi-energy field composite welding method for enhanced penetration of ultra-thick plates according to this specific embodiment. It can be seen that the welding wire of the arc heat source 7 penetrates into the groove portion 1 of the Y-shaped groove structure and generates a welding arc towards the root of the groove portion 1; the groove edge (i.e., the ramp 11) is located on both sides of the welding wire; the long arc 71 is formed in the gap of the butt joint portion 2 of the Y-shaped groove structure and passes through the gap to reach the bottom of the Y-shaped groove structure. Figure 22 and Figure 23 The image shows a high-speed image of the formation and maintenance of a long electric arc 71 in the multi-energy field composite welding method for enhanced penetration of ultra-thick plates according to this specific embodiment. It can be seen that the molten droplet 6 is located above the root of the groove portion 1 of the Y-shaped groove structure, and the long electric arc 71 is maintained in the gap of the mating portion 2 of the Y-shaped groove structure, always ensuring that it can reach the bottom of the Y-shaped groove structure. Figure 22 The T marked in the figure represents the start time of the unit pulse period, where the unit pulse period refers to the welding transition method used in the welding method described in the embodiments of the present invention, which is pulse transition.

[0114] The relationship between the arc voltage and arc length of the ultra-thick plate is shown in Table 3.

[0115] Table 3. Relationship between arc voltage and arc length

[0116] Therefore, the specific embodiments of this invention employ the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates. Targeting ultra-thick aluminum alloy plates exceeding 20mm in thickness, the method utilizes a large blunt edge, narrow bevel, and gentle bottom bevel design. This effectively reduces weld filler, reliably ensures the assembly gap of the welded joint, and effectively resists deformation during welding, guaranteeing a stable joint gap. During the welding process, this method effectively utilizes laser-arc composite welding. By creating a long arc 71 induction environment, long arc 71 welding can be performed. Furthermore, arc information is collected and fed back during welding, and welding parameters are adjusted in real time based on this information to maintain the long arc 71 welding process.

[0117] Another control group was selected for comparison with the above-described embodiments. In this control group, the dimensions of the two plates of the ultra-thick plate were the same as those in the specific embodiments described above, but the bevel structure between the two plates adopted a conventional V-shaped bevel. This control group was welded using ordinary arc welding.

[0118] Comparative experiments show that weldments obtained using the aforementioned multi-energy field composite welding method for enhancing ultra-thick plate penetration are as follows: Figure 24 and Figure 25 As shown, Figure 25 The 10mm shown and the line segment below it serve as a unit reference length scale with a length of 10mm. Figure 25 The plate thickness shown is not less than two scale lengths, meaning the plate thickness is greater than or equal to 20 mm. Welded parts obtained using the welding method of the control group are shown below. Figure 26 and Figure 27 As shown in the comparison, the number of weld beads in the welded parts obtained by the above-mentioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates is significantly reduced, the structural strength of the molten pool metallographic structure is significantly stronger, and the welding quality is better.

[0119] The welding apparatus provided by the present invention will be described below. The welding apparatus described below can be referred to in correspondence with the method described above.

[0120] The multi-energy field composite welding device for enhancing the penetration of ultra-thick plates described in this embodiment of the invention is capable of performing the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates. This multi-energy field composite welding device for enhancing the penetration of ultra-thick plates includes an arc module, a laser module, and a drive module. The arc module forms an arc heat source 7. The laser module forms a laser heat source 8. The laser module is used to construct a plasma environment in the Y-shaped groove structure using the plasma environment laser heat source 8, and to utilize the plasma environment laser heat source 8 and the plasma environment plasma environment to act together on the plasma environment arc heat source 7, so that the plasma environment arc heat source 7 forms a long arc 71, thereby ensuring that the long arc 71 reaches at least the bottom of the plasma environment Y-shaped groove structure. The drive module connects the plasma environment laser module and the plasma environment arc module, and is used to drive the plasma environment laser heat source 8 and the plasma environment arc heat source 7 to weld along the plasma environment Y-shaped groove structure. This welding apparatus, by performing the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates, possesses all the advantages of the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates, which will not be elaborated here.

[0121] In some embodiments, the welding apparatus further includes a welding monitoring module, which is capable of performing the aforementioned steps of maintaining and dynamically adjusting the long arc 71. Specifically, the welding monitoring module is connected to the plasma environment laser module and the plasma environment arc module, and is used to collect and monitor the arc information at the bottom of the Y-shaped groove structure in the plasma environment in real time, and can adjust the arc voltage of the plasma environment arc heat source 7 online based on the plasma environment arc information. By performing the steps of maintaining and dynamically adjusting the long arc 71 in the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates, the welding apparatus possesses all the advantages corresponding to the steps of maintaining and dynamically adjusting the long arc 71 in the aforementioned multi-energy field composite welding method for enhancing the penetration of ultra-thick plates, which will not be elaborated further here.

[0122] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-energy field composite welding method for enhancing the penetration of ultra-thick plates, characterized in that, Includes the following steps: A plasma environment is constructed in a Y-shaped bevel structure using a laser heat source, wherein the Y-shaped bevel structure is located at the joint of two plates to be welded. The laser heat source and the plasma environment work together to form a long electric arc, which can reach at least the bottom of the Y-shaped groove structure. The laser heat source is arranged in front of the welding direction, and the electric arc heat source is arranged behind the laser. The groove of the Y-shaped groove is approximately U-shaped. The step of constructing a plasma environment in the Y-shaped bevel structure using a laser heat source further includes: Laser-assisted composite welding is used to weld along the length of the Y-shaped groove structure. The laser-assisted composite welding includes a laser heat source and an electric arc heat source, with the laser heat source located in front of the electric arc heat source. The laser beam formed by the laser heat source includes a laser beam emitting section, a laser beam focal section, and a laser beam acting section. The laser beam acting section of the laser heat source at least covers the docking section of the Y-shaped bevel structure so that the docking section forms the plasma environment. The step of having the laser beam of the laser heat source at least cover the docking portion of the Y-shaped bevel structure to form the plasma environment at the docking portion further includes: The laser beam acts at least on the top of the mating joint to melt the base material at the top of the mating joint. A portion of the molten base material flows to the bottom of the joint, while another portion is heated and vaporized to form plasma. The plasma is located in the gap of the joint to construct the plasma environment in the gap of the joint.

2. The multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to claim 1, characterized in that, The step of utilizing the laser heat source and the plasma environment to act together on the electric arc heat source, so that the electric arc heat source forms a long electric arc, thereby ensuring that the long electric arc can at least reach the bottom of the Y-shaped bevel structure, further includes: The electric arc heat source acts on the joint of the Y-shaped bevel structure and forms a conventional electric arc; Based on the suppressive effect of the laser heat source and the guiding effect of the plasma environment, the conventional electric arc is induced and transformed into the long electric arc.

3. The multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to claim 2, characterized in that, The stiffness of the long electric arc is greater than that of the conventional electric arc, and the arc length of the long electric arc is greater than that of the conventional electric arc.

4. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to claim 1, characterized in that, The multi-energy field composite welding method for enhancing the penetration of ultra-thick plates also includes the following steps: Real-time acquisition and monitoring of electric arc information at the bottom of the Y-shaped bevel structure; Based on the arc information, the arc voltage of the arc heat source is adjusted online.

5. The multi-energy field composite welding method for enhancing the penetration of ultra-thick plates according to claim 4, characterized in that, The step of adjusting the arc voltage of the arc heat source online based on the arc information further includes: The arc information includes the arc signal and the arc length; If the arc signal can be collected at the bottom of the Y-shaped bevel structure, then it is further determined whether the arc length exceeds the bottom of the Y-shaped bevel structure. If so, the current arc voltage is reduced; otherwise, the arc voltage is kept unchanged. If the arc signal is not detected at the bottom of the Y-shaped bevel structure, the current arc voltage is increased until the arc signal can be detected at the bottom of the Y-shaped bevel structure.

6. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to any one of claims 1-5, characterized in that, The Y-shaped bevel structure includes: The mating part is vertically arranged and formed between the mating end faces of the two plates, and a gap is formed between the mating end faces of the two plates at the position of the mating part; The bevel portion is connected to the mating portion and is located near the welding surface of the mating portion.

7. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to claim 6, characterized in that, The bevel portion includes a ramp and a bottom, which are sequentially connected between the welding surface and the mating portion.

8. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to claim 7, characterized in that, The ramp is inclined downward relative to the surface of the plate; and the ramps on the two plates gradually approach each other from the welding surface to the mating portion.

9. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to claim 7, characterized in that, The bottom of the slope is an arc-shaped slope, and the slope of the bottom of the slope is less than or equal to the slope of the ramp.

10. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to claim 6, characterized in that, The two plates include a first plate and a second plate, with the end face of the first plate abutting against the end face of the second plate and forming a gap; the mating portion includes a plurality of protruding joints, all of which are located within the gap.

11. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to claim 10, characterized in that, The mating part includes at least two of the aforementioned protruding joints, all of which are fixed to the end face of the first plate and can contact the end face of the second plate.

12. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to claim 11, characterized in that, The adjacent male connectors are spaced apart.

13. The multi-energy field composite welding method for enhancing penetration of ultra-thick plates according to any one of claims 1-5, characterized in that, The thickness of both plates is greater than or equal to 20 mm.

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