阅读说明：本技术 一种铝合金厚板多层激光-tig复合焊接装置及方法 (Multilayer laser-TIG (tungsten inert gas) hybrid welding device and method for aluminum alloy thick plate ) 是由 彭进 许红巧 龙伟民 王星星 于 2020-06-23 设计创作，主要内容包括：一种铝合金厚板多层激光-TIG复合焊接装置及方法,包括两个TIG电源、两把TIG焊枪、一个热丝电源和一个激光器,两个TIG电源和热丝电源配合,从而形成不同功率、不同位置和不同作用的三个电弧,并与激光束进行复合,从而实现了显著提高焊丝的熔化率,提高填充和盖面的焊接效率,而且解决激光熔化焊接工件时对坡口间隙适应性差的问题。本发明在焊接时,熔池后方具有保护熔池防止其氧化的TIG电弧保护气,可以保护焊接熔池防止其氧化,而且与MIG电弧相比TIG电弧焊接过程中焊接较为稳定,不易出现剧烈的焊接飞溅的情况,因此可去除每层填充焊后对焊道及其附近待焊区域清洗打磨工序,提高焊接效率。(A multilayer laser-TIG hybrid welding device and method for an aluminum alloy thick plate comprises two TIG power supplies, two TIG welding guns, a hot wire power supply and a laser, wherein the two TIG power supplies are matched with the hot wire power supply to form three electric arcs with different powers, different positions and different actions, and the three electric arcs are combined with a laser beam, so that the melting rate of a welding wire is obviously improved, the welding efficiency of filling and capping is improved, and the problem of poor adaptability to a groove gap when a workpiece is welded by laser melting is solved. During welding, the TIG arc shielding gas for protecting the molten pool from oxidation is arranged behind the molten pool, so that the welding molten pool can be protected from oxidation, and the welding is more stable in the TIG arc welding process compared with the MIG arc, and the condition of violent welding spatter is not easy to appear, so that the cleaning and polishing process of a welding track and a to-be-welded area nearby the welding track after each layer of filling welding can be removed, and the welding efficiency is improved.)

1. The utility model provides an aluminum alloy thick plate multilayer laser-TIG hybrid welding device which characterized in that: the welding device comprises a first TIG power supply (9), a second TIG power supply (1) and a hot wire power supply (8), wherein the negative electrode and the positive electrode of the first TIG power supply (9) are respectively connected with a first TIG welding gun (5) and an aluminum alloy thick plate (10) to be welded, so that a molten pool arc (12) is formed between the first TIG welding gun (5) and the aluminum alloy thick plate (10) to be welded; the negative electrode and the positive electrode of the hot wire power supply (8) are respectively connected with the first TIG welding gun (5) and the welding wire (7), so that a fuse arc (11) is formed between the bottom ends of the first TIG welding gun (5) and the welding wire (7); and the negative electrode and the positive electrode of the second TIG power supply (1) are respectively connected with the second TIG welding gun (2) and the aluminum alloy thick plate (10) to be welded, so that a heating arc (13) is formed between the second TIG welding gun (2) and the aluminum alloy thick plate (10) to be welded, and a laser for emitting a laser beam (4) towards the surface of the aluminum alloy thick plate (10) to be welded is arranged between the first TIG welding gun (5) and the second TIG welding gun (2).

2. The multi-layer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 1, characterized in that: the first TIG welding gun (5) is controlled by an ultrasonic amplitude transformer (3) to vibrate in a reciprocating mode along the welding direction in the welding process.

3. The multi-layer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 1, characterized in that: the welding wire (7) is controlled by a wire feeding mechanism (6) to feed wires.

4. A welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 1 or 2, which is to perform backing welding first and then perform filling and facing welding, characterized in that:

1) during backing welding, a first TIG welding torch (5) is arranged in front of the laser beam (4) in the welding direction and is connected to a first TIG power supply (9) and a hot wire power supply (8) according to the method of claim 1; a second TIG welding torch (2) is arranged behind the laser beam (4) and connected to the second TIG power supply (1) according to the method of claim 1 or to the second TIG power supply (1) and the ultrasonic horn (3) according to the method of claim 2, after which the welding operation is performed;

2) in filling and facing welding, a second TIG welding gun (2) is placed in front of the laser beam (4) in the welding direction and is connected to a second TIG power supply (1) according to the method of claim 1 or to a second TIG power supply (1) and an ultrasonic horn (3) according to the method of claim 2; a first TIG welding gun (5) is arranged behind the laser beam (4) and connected to a first TIG power supply (9) and a hot wire power supply (8) according to the method of claim 1, after which the welding operation is performed.

5. The welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 4, characterized in that: before the backing welding, a Y-shaped or U-shaped groove needs to be machined on the aluminum alloy thick plate (10) to be welded, meanwhile, the surface of a welding workpiece is treated, and then the welding workpiece and the groove of the aluminum alloy thick plate (10) to be welded are connected and fixed by a welding clamp.

6. The welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 4, characterized in that: during the backing welding or the filling and cover welding, a protective gas is required to be opened to protect the molten pool from being oxidized.

7. The welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 4, characterized in that: the distance between the tungsten needles of the first TIG welding gun (5) and the second TIG welding gun (2) and the aluminum alloy thick plate (10) to be welded is 0-6mm, and the included angle theta between the first TIG welding gun (5) and the horizontal plane₁Is 40-80 degrees, and the included angle theta between the second TIG welding gun (2) and the horizontal plane₂Is 40-80 degrees.

8. The welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 4, characterized in that: the current of the first TIG power supply (9) is 20-300A, the current of the second TIG power supply (1) is 20-150A, and the current of the hot wire power supply (8) is 50-400A.

9. The welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 4, characterized in that: the diameter of the welding wire (7) is 0.8-3mm, and the wire feeding speed is 0.2-20 m/min.

10. The welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate according to claim 4, characterized in that: the ultrasonic vibration frequency of the ultrasonic amplitude transformer (3) is 5-900kHz, and the vibration amplitude is 1-10 um.

Technical Field

The invention relates to the field of welding of aluminum alloy plates, in particular to a multilayer laser-TIG (tungsten inert gas) hybrid welding device and method for an aluminum alloy thick plate.

Background

Because the aluminum alloy has good electrical and thermal conductivity, large linear expansion coefficient and good fluidity in a liquid state, and a layer of oxide film is arranged on the surface of the aluminum alloy, the defects of air holes, undercut, poor weld seam formation and the like often occur in welding. The traditional welding method of the aluminum alloy thick plate generally adopts multilayer multi-pass welding. The traditional welding method has the disadvantages of large heat input, wide heat affected zone, coarse grains, easy generation of welding deformation and residual stress and poor mechanical property of a welding joint.

The chinese patent published as 2015.04.29 discloses a thick plate multilayer laser-MIG hybrid welding method, which discloses backing welding a workpiece by a laser rear-mounted mode; and cleaning and polishing a welding seam formed by backing welding, and filling and facing welding in a laser preposing mode. After each layer of filling welding is carried out, the welding channel and the area to be welded nearby the welding channel need to be cleaned and polished, and the welding efficiency is reduced. And the MIG electric arc is easy to generate the condition of liquid metal splashing in the welding process, the welding seam quality is influenced, meanwhile, the welding current needs to be increased for increasing the melting rate of a welding wire, so that the welding seam heat input is overlarge, and the defects of large deformation of a welding workpiece, large texture crystal grains and poor mechanical property can be caused.

Disclosure of Invention

The invention provides a multilayer laser-TIG composite welding device and a method for an aluminum alloy thick plate, wherein the device utilizes two TIG welding guns, two TIG power supplies and a hot wire power supply to generate three electric arcs with different actions, and the three electric arcs are compounded with laser, so that welding wires flow into a molten pool formed by laser beams after being melted.

The technical scheme adopted by the invention for solving the technical problems is as follows: a multilayer laser-TIG (tungsten inert gas) hybrid welding device for an aluminum alloy thick plate comprises a first TIG power supply, a second TIG power supply and a hot wire power supply, wherein a negative electrode and a positive electrode of the first TIG power supply are respectively connected with a first TIG (tungsten inert gas) welding gun and the aluminum alloy thick plate to be welded, so that a molten pool electric arc is formed between the first TIG welding gun and the aluminum alloy thick plate to be welded; the negative electrode and the positive electrode of the hot wire power supply are respectively connected with the first TIG welding gun and the welding wire, so that a fuse wire arc is formed between the first TIG welding gun and the bottom end of the welding wire; and a laser for emitting laser beams towards the surface of the aluminum alloy thick plate to be welded is arranged between the first TIG welding gun and the second TIG welding gun.

As an improvement of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate, the first TIG welding gun is controlled by an ultrasonic amplitude transformer to vibrate back and forth along the welding direction in the welding process.

As another improvement of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate, the welding wire is controlled by a wire feeding mechanism to feed.

The welding method of the multilayer laser-TIG composite welding device for the aluminum alloy thick plate comprises the following steps of backing welding, filling and facing welding, wherein:

1) during backing welding, a first TIG welding gun is arranged in front of a laser beam along the welding direction and is connected with a first TIG power supply and a hot wire power supply according to the method; the second TIG welding gun is arranged behind the laser beam and is connected with a second TIG power supply according to the method, or is connected with the second TIG power supply and the ultrasonic amplitude transformer according to the method, and then welding operation is carried out;

2) during filling and facing welding, the second TIG welding gun is arranged in front of the laser beam along the welding direction and is connected with a second TIG power supply according to the method, or is connected with the second TIG power supply and an ultrasonic amplitude transformer according to the method; a first TIG welding gun is arranged behind the laser beam and connected to a first TIG power supply and a hot wire power supply according to the method described before the welding operation is performed.

As an improved scheme of the welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate, before the backing welding, a Y-shaped or U-shaped groove needs to be processed on the aluminum alloy thick plate to be welded, meanwhile, the surface treatment is performed on the welding workpiece, and then the welding workpiece and the groove of the aluminum alloy thick plate to be welded are connected and fixed by a welding fixture.

As another improvement of the welding method of the multilayer laser-TIG hybrid welding device for the aluminum alloy thick plate, protective gas is required to be started to protect a molten pool from being oxidized during backing welding or filling and cover welding.

As another improvement of the welding method of the multilayer laser-TIG composite welding device for the aluminum alloy thick plate, the distance between the tungsten needles of the first TIG welding gun and the second TIG welding gun and the aluminum alloy thick plate to be welded is 0-6mm, and the included angle theta between the first TIG welding gun and the horizontal plane is₁Is 40-80 degrees, and the included angle theta between the second TIG welding gun and the horizontal plane₂Is 40-80 degrees.

As another improvement of the welding method of the multilayer laser-TIG composite welding device for the aluminum alloy thick plate, the current of the first TIG power supply is 20-300A, the current of the second TIG power supply is 20-150A, and the current of the hot wire power supply is 50-400A.

As another improvement of the welding method of the multilayer laser-TIG composite welding device for the aluminum alloy thick plate, the diameter of the welding wire is 0.8-3mm, and the wire feeding speed is 0.2-20 m/min.

As another improvement of the welding method of the multilayer laser-TIG composite welding device for the aluminum alloy thick plate, the ultrasonic vibration frequency of the ultrasonic amplitude transformer is 5-900kHz, and the vibration amplitude is 1-10 um.

Compared with the prior art, the invention has the following beneficial effects:

1) the composite welding device utilizes the hot wire power supply to form the fuse wire arc between the first TIG welding gun and the welding wire, the fuse wire arc is used for heating the welding wire to melt the welding wire, so that the melting rate of the welding wire is obviously improved and the welding efficiency of filling and capping is improved under the condition of not increasing the heat input of an aluminum alloy thick plate to be welded, and a melt formed by the melted welding wire flows into a groove gap in advance, thereby solving the problem that the adaptability of a laser melting welding workpiece to the groove gap is poor during backing welding;

a first TIG power supply is utilized to form a molten pool electric arc between a first TIG welding gun and the aluminum alloy thick plate to be welded, the electric arc can generate a composite action with a laser beam, the welding stability can be improved, and the weld penetration can be increased;

forming a heating electric arc between a second TIG welding gun and the aluminum alloy thick plate to be welded by using a second TIG power supply;

when backing welding is carried out, the heating electric arc can act on a molten pool formed by a laser beam and a molten pool electric arc, so that the solidification time of the molten pool is prolonged, welding bubbles can conveniently escape from the molten pool, the porosity of a welding seam is reduced, and the molten pool can be protected by protective gas during welding to prevent the molten pool from being oxidized in the solidification process; when filling and cover surface welding are carried out, the heating electric arc is in front, the thick aluminum alloy plate to be welded can be preheated, the oxide film on the surface of the aluminum alloy can be eliminated, and the laser energy utilization rate of a laser beam acting on a welding workpiece is improved (because the solid aluminum alloy can emit the energy of the laser beam, the laser energy utilization rate acting on a base metal is reduced);

2) in the composite welding device, the second TIG welding gun is connected with the ultrasonic amplitude transformer, so that heating electric arc generated by the second TIG welding gun can reduce heat input to a base metal, simultaneously, a molten pool is stirred by using the vibration action of the ultrasonic amplitude transformer, the solidification time of the molten pool is prolonged, welding bubbles can escape from the molten pool, and the porosity of a welding seam of backing welding is reduced.

3) In the invention, when the bottoming, filling and cover welding are carried out, the TIG arc shielding gas for protecting the molten pool from oxidation is arranged behind the molten pool, so that the welding molten pool can be protected from oxidation, and the welding is more stable in the TIG arc welding process compared with the MIG arc, and the condition of violent welding spatter is not easy to occur, so that the cleaning and polishing process of the welding track and the area to be welded nearby the welding track after each layer of filling welding can be removed, and the welding efficiency is improved.

Drawings

FIG. 1 is a schematic view of the operation of the backing weld of the present invention;

FIG. 2 is a schematic diagram of the operation of the present invention during fill and cap welding;

FIG. 3 is a schematic cross-sectional view of a weld joint obtained by a conventional multi-layer laser-MIG arc hybrid welding method for an aluminum alloy thick plate;

FIG. 4 is a schematic cross-sectional view of a weld resulting from the welding method of the present invention;

reference numerals: 1. the welding device comprises a second TIG power supply, 2, a second TIG welding gun, 3, an ultrasonic amplitude transformer, 4, a laser beam, 5, a first TIG welding gun, 6, a wire feeding mechanism, 7, a welding wire, 8, a hot wire power supply, 9, a first TIG power supply, 10, a thick aluminum alloy plate to be welded, 11, a fuse wire arc, 12, a molten pool arc, 13 and a heating arc.

Detailed Description

The technical solution of the present invention is further described in detail with reference to the following specific embodiments. The specific structures and mounting and connecting methods of the laser, the TIG power supply, the hot wire power supply, the TIG welding gun, the wire feeding mechanism, the ultrasonic horn, etc., which are not specifically described in the following embodiments, are all known in the art, and are not described herein again.