Welding penetration prevention dissimilar aluminum alloy unequal thickness thick plate corner joint welding method

Abstract

The invention provides an anti-weld-penetration dissimilar aluminum alloy unequal-thickness thin plate corner joint welding method, belongs to the technical field of electric arc welding, can prevent the problem that a thin plate is easy to weld through caused by an existing CMT welding production process, can reduce joint deformation and inhibit undercut, and enables a weld joint to be attractive in forming and good in consistency.

Description

Technical Field

[0001] The invention belongs to the technical field of arc welding, and in particular relates to a welding method for a fillet joint of heterogeneous aluminum alloy thin plates of unequal thickness that prevents welding penetration. Background Art

[0002] The use of advanced manufacturing processes, optimized structural design and application of lightweight materials are the three major technical means of lightweighting automobiles. Among them, the use of lightweight materials is the most direct and effective way. Aluminum alloys have high specific strength and excellent processing performance. Compared with high-strength steel, magnesium alloys, carbon fiber, etc., they have advantages such as low cost and mature technology. They are widely used in the lightweight field of new energy vehicles; such as aluminum alloy profile heat exchanger system components, body frames, doors, etc., cast aluminum alloy accelerator pedals, wheels, steering wheels, motor housings, etc.

[0003] In the production process of new energy vehicles, there are many parts that need to weld two aluminum alloy thin plate parts. The two thin plates are often made of different aluminum alloy materials. For example, the welding between the bottom plate of the battery box of new energy vehicles and the horizontal and longitudinal beams is made of die-cast AlSi10MnMg / 6005A-T6 aluminum profiles, and the thickness of the thin plates is different. The elongation and weldability between the two are quite different. During welding, problems such as excessive heat input, large deformation and even thin plate welding penetration often occur, which seriously affects the yield of parts. Summary of the invention

[0004] In order to solve the defects of the prior art, the present invention provides a welding method for fillet joints of dissimilar aluminum alloy thin plates of unequal thickness that is resistant to welding penetration, comprising: assembling a die-cast aluminum plate and an aluminum profile plate in the form of a J-shaped fillet joint with a small gap; then tack welding the assembled fillet joint; then CMT welding the tack-welded fillet joint using a welding wire; during the CMT welding process, the welding gun angle is kept biased toward the thinner plate side, and the angle ratio between the welding wire and the two plates is equal to the plate thickness ratio of the two plates to avoid excessive heat concentration on the thin plate.

[0005] Preferably, the die-cast aluminum plate is made of die-cast AlSi10MnMg.

[0006] Preferably, the aluminum profile plate is 6005A-T6 aluminum profile.

[0007] Preferably, a hand-held laser welding gun is used to perform tack welding on the assembled fillet joint.

[0008] Preferably, the welding wire is AlSi5-4043 welding wire.

[0009] Preferably, during the CMT welding process, the process parameters are adjusted to use a smaller heat input while maintaining a good transition of the molten droplets, so as to prevent the die-cast AlSi10MnMg base material from excessively melting and precipitating a large amount of gas.

[0010] Preferably, during CMT welding, the welding gun angle is controlled at 55° to 65°.

[0011] Preferably, during CMT welding, the welding current is controlled at 100-140A.

[0012] Preferably, during CMT welding, the welding voltage is controlled at 14-15V.

[0013] Preferably, during the CMT welding process, the welding speed is controlled at 8 to 10 mm / s.

[0014] The advantages and beneficial effects of the present invention are as follows: the present invention provides a CMT welding method for fillet joints of dissimilar aluminum alloy thin plates of unequal thickness, belonging to the technical field of arc welding. The present invention can prevent the problem of easy welding through of thin plates caused by the existing CMT welding production process. The present invention can reduce joint deformation and inhibit undercutting, so that the weld is beautiful and consistent. DETAILED DESCRIPTION

[0015] The specific implementation of the present invention is further described below in conjunction with the examples. The following examples are only used to more clearly illustrate the technical solutions of the present invention, and cannot be used to limit the protection scope of the present invention.

[0016] The technical solutions specifically implemented in the present invention are as follows: The present invention provides a welding method for a fillet joint of dissimilar aluminum alloy thin plates with unequal thickness and anti-welding properties, comprising: assembling a die-cast aluminum plate and an aluminum profile plate in the form of a J-shaped fillet joint with a small gap; then using a handheld laser welding gun to perform positioning welding on the assembled fillet joint; then using a welding wire to perform CMT welding on the position-welded fillet joint; during the CMT welding process, the welding gun angle is kept biased toward the thinner plate side, and the angle ratio between the welding wire and the two plates is equal to the plate thickness ratio of the two plates, so as to avoid excessive heat being concentrated on the thin plate; The die-cast aluminum sheet adopts die-cast AlSi10MnMg; The aluminum profile plate adopts 6005A-T6 aluminum profile; The welding wire is AlSi5-4043 welding wire; During CMT welding, the process parameters are adjusted to use a smaller heat input while maintaining a good droplet transition to prevent excessive melting of the die-cast AlSi10MnMg base material and the precipitation of a large amount of gas; More specifically, during the CMT welding process, the welding gun angle is controlled at 55° to 65°, the welding current is controlled at 100 to 140A, the welding voltage is controlled at 14 to 15V, and the welding speed is controlled at 8 to 10mm / s.

[0017] The present invention can prevent the problem of easy welding through of thin plates caused by the existing CMT welding production process. The present invention can reduce joint deformation and inhibit undercutting, so that the weld is beautifully formed and has good consistency.

[0018] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A welding method for welding fillet joints of heterogeneous aluminum alloy plates of unequal thickness to prevent welding penetration, characterized in that: include: Assemble the die-cast aluminum sheet and aluminum profile sheet in the form of J-shaped corner joints with a small gap; Then, the assembled fillet joint is tack welded; then, the tack welded fillet joint is CMT welded using welding wire; during the CMT welding process, the welding gun is angled toward the thinner plate, and the angle ratio between the welding wire and the two plates is equal to the plate thickness ratio of the two plates to avoid excessive heat concentration on the thin plate.

2. The welding method for the fillet joint of heterogeneous aluminum alloy thin plates of unequal thickness to prevent welding penetration according to claim 1 is characterized in that: The die-cast aluminum sheet adopts die-cast AlSi10MnMg.

3. The welding method for weld-through-proof fillet joints of heterogeneous aluminum alloy thin plates of unequal thickness according to claim 2 is characterized in that: The aluminum profile plate adopts 6005A-T6 aluminum profile.

4. The welding method for welding fillet joints of heterogeneous aluminum alloy thin plates of unequal thicknesses to prevent welding penetration according to claim 3 is characterized in that: The completed assembly is tack welded using a handheld laser welding torch.

5. The welding method for welding fillet joints of heterogeneous aluminum alloy thin plates of unequal thicknesses to prevent welding penetration according to claim 4 is characterized in that: The welding wire is AlSi5-4043 welding wire.

6. The welding method for weld-through-proof fillet joints of heterogeneous aluminum alloy thin plates of unequal thickness according to claim 5 is characterized in that: During CMT welding, the process parameters are adjusted to use a smaller heat input while maintaining a good transition of the molten droplet to prevent the die-cast AlSi10MnMg base material from excessive melting and precipitation of a large amount of gas.

7. The welding method for weld-through-proof fillet joints of heterogeneous aluminum alloy thin plates of unequal thickness according to claim 6 is characterized in that: During CMT welding, the welding gun angle is controlled at 55° to 65°.

8. The welding method for weld-through-proof fillet joints of heterogeneous aluminum alloy thin plates of unequal thickness according to claim 7 is characterized in that: During CMT welding, the welding current is controlled at 100-140A.

9. The welding method for fillet joints of heterogeneous aluminum alloy thin plates of unequal thicknesses to prevent welding penetration according to claim 8 is characterized in that: During CMT welding, the welding voltage is controlled at 14-15V.

10. The welding method for fillet joints of heterogeneous aluminum alloy thin plates of unequal thicknesses to prevent welding penetration according to claim 9 is characterized in that: During CMT welding, the welding speed is controlled at 8 to 10 mm / s.