New energy automobile aluminum alloy battery tray die casting and profile welding method

Abstract

The invention provides a new energy automobile aluminum alloy battery tray die casting and profile welding method. The new energy automobile aluminum alloy battery tray die casting and profile welding method comprises the following steps that S1, surface cleaning is conducted before welding; s2, analyzing the weldability of the aluminum alloy die casting material; s3, the machining size of the groove of the aluminum alloy die casting is welded; s4, setting a set value of a welding process of the aluminum alloy die casting and the aluminum alloy profile. According to the method, surface cleaning before welding is adopted, and the technical defects that in the prior art, release agent residues exist on the outer surface of an aluminum alloy die casting, and slag inclusion, near-surface-layer air holes and near-surface-layer cracks are likely to be generated during welding are overcome; aluminum alloy die casting material weldability analysis is adopted, and the technical defect that aluminum alloy die castings are not thoroughly cleaned before being welded is overcome; according to the machining size of the groove for welding the aluminum alloy die casting, single-side horn-shaped and single-V-shaped butt welding seams are mainly used, and the technical defects that in the prior art, due to the fact that the groove angle is too small, the truncated edge is too large, and a gap is too small, the penetration performance during welding can be affected, and incomplete fusion or incomplete penetration is caused are overcome.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, and particularly relates to a welding method for aluminum alloy die-castings and profiles of a new energy vehicle battery tray. Background Art

[0002] In recent years, aluminum alloy die-castings have the characteristics of light weight, strong corrosion resistance, good mechanical properties, high thermal conductivity and electrical conductivity, and have been widely used in many fields such as automobiles, household appliances, communications, energy storage, etc. In recent years, with the rapid development of industries such as automobiles and energy storage, the application demand for aluminum alloy die-castings has been continuously released, and its market has also shown a good development trend. Due to the booming development of new energy vehicles, the demand for vehicle lightweighting is becoming stronger and stronger, and it has been widely used in various system structural parts of vehicles. Especially in the field of battery trays, with the improvement of the manufacturing performance of aluminum alloy die-castings, it has gradually become a trend to replace the proportion of aluminum alloy profiles in some product structures. However, there are the following technical defects in the welding of the two: if there is residual mold release agent on the external surface of the aluminum alloy die-casting, the surface of the aluminum alloy die-casting is not thoroughly cleaned before welding, and slag inclusions, near-surface pores, and near-surface cracks are likely to occur during welding; the internal organizational structure of the aluminum alloy die-casting is loose, easy to absorb moisture, and internal pores and internal cracks are likely to occur due to thermal expansion during welding; the internal organization of the aluminum alloy die-casting contains impurities, and internal slag inclusions and internal cracks are likely to occur during welding; if the welding speed is too fast, the gas in the molten pool has no time to escape; too small groove angle, too large root face, too small gap, etc. will all affect the penetration during welding, resulting in incomplete fusion or incomplete penetration; improper selection of welding parameters, such as too large welding current, too fast welding speed, etc., will overheat the weld seam, generate large thermal stress, and thus lead to the generation of cracks.

[0003] Therefore, how to design a welding method for aluminum alloy die-castings and profiles of a new energy vehicle battery tray has become an urgent problem to be solved. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the present invention provides a welding method for aluminum alloy die-castings and profiles of a new energy vehicle battery tray to solve at least one of the above technical problems.

[0005] The technical solution of the present invention is: a welding method for aluminum alloy die-castings and profiles of a new energy vehicle battery tray, comprising the following steps:

[0006] S1. Surface cleaning before welding,

[0007] Remove the surface mold release agent from the aluminum alloy die-casting before welding and clean the surface of the aluminum alloy die-casting thoroughly;

[0008] S2. Weldability analysis of the aluminum alloy die-casting material,

[0009] ① The material of the aluminum alloy die-casting is CMM.ALSi10MnMg.F; the material of the aluminum alloy profile is 6061. Autogenous welding without filler wire is carried out on the aluminum alloy die-casting by argon arc welding.

[0010] ② For the welding judgment of the aluminum alloy die-casting, the judgment method is that there are no obvious pores on the weld surface, the fluidity of the solution is good during the test welding, and the weld bead is bright.

[0011] ③ The welding of the aluminum alloy die-casting is suitable for small current and slow welding speed, and any one of the positive circle swing or the elliptical circle swing can be adopted.

[0012] S3. Machining dimensions of the groove for welding the aluminum alloy die-casting

[0013] ① A first single V-groove is opened at one end of the aluminum alloy profile close to the aluminum alloy die-casting, and a second single V-groove is opened at one end of the aluminum alloy die-casting close to the aluminum alloy profile. The root face is 1 mm, the assembly gap is 0 mm, and the groove angle after the assembly of the first single V-groove and the second single V-groove is 60°.

[0014] ② Within a range of 20 mm on both sides of the front and back of the weld bead, the oxide film is removed with a wire brush.

[0015] S4. Set values of the welding process for the aluminum alloy die-casting and the aluminum alloy profile

[0016] Welding method; MIG welding function of the robot-equipped welding machine;

[0017] Welding curve; Pulse GMAW universal 1 / 1 3555;

[0018] Wire rod grade; 4043, with a diameter of ϕ1.2 mm;

[0019] Welding shielding gas; pure argon, and the gas flow rate of pure argon is 22 L / min.

[0020] The present invention adopts surface cleaning before welding, which solves the technical defects of the prior art that there is release agent residue on the external surface of aluminum alloy die-castings, and slag inclusions, near-surface pores, and near-surface cracks are likely to occur during welding; by analyzing the weldability of the aluminum alloy die-casting material and the incomplete cleaning before welding of the aluminum alloy die-casting, it solves the technical defects of the prior art that the internal organizational structure of the aluminum alloy die-casting is loose, easy to absorb moisture, and internal pores and internal cracks are likely to occur due to thermal expansion during welding; it solves the technical defects of the prior art that the internal structure of the aluminum alloy die-casting contains impurities and internal slag inclusions and internal cracks are likely to occur during welding; the processing dimensions of the welding groove of the aluminum alloy die-casting are mainly unilateral trumpet-shaped and single-V butt welds, which solves the technical defects of the prior art that too small groove angle, too large root face, too small gap, etc. will all affect the penetrability during welding and result in incomplete fusion or incomplete penetration; the method of setting values for the welding process of aluminum alloy die-castings and aluminum alloy profiles solves the technical defects of the prior art that improper selection of welding parameters, such as too large welding current, too fast welding speed, etc., will cause the weld to overheat and generate large thermal stress, thus resulting in crack generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is the front view before welding of the present invention.

[0022] Figure 2 is the top view during welding of the present invention.

[0023] Figure 3 is Figure 2 the top view of the welding torch rotating towards the direction of the aluminum alloy profile.

[0024] In the figure: 1. Aluminum alloy profile; 2. Aluminum alloy die-casting. DETAILED DESCRIPTION OF THE INVENTION

[0025] The present invention will be further described below with reference to the accompanying drawings.

[0026] Refer to Figure 1-2 , the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in this technology to understand and read, and are not used to limit the implementation conditions of the present invention. Therefore, they do not have technical essential significance. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle", and "one" cited in this specification are only for the convenience of clear narration and are not used to limit the implementation scope of the present invention. The change or adjustment of their relative relationships, without substantial change in the technical content, should also be regarded as the scope in which the present invention can be implemented.

[0027] Example 1. A welding method for an aluminum alloy battery tray die-casting and profile of a new energy vehicle, refer to Figure 1 , Figure 2 , including the following steps:

[0028] S1. Surface cleaning before welding,

[0029] Before welding, remove the surface release agent from the aluminum alloy die-casting 2 and clean the surface of the aluminum alloy die-casting 2 thoroughly.

[0030] S2. Weldability analysis of the aluminum alloy die-casting material,

[0031] ① The material of the aluminum alloy die-casting 2 is CMM.ALSi10MnMg.F; the material of the aluminum alloy profile 1 is 6061. Use GTAW to perform autogenous welding without filler wire on the aluminum alloy die-casting 2.

[0032] ② Welding judgment of the aluminum alloy die-casting 2. The judgment method is that there are no obvious pores on the weld surface, the solution has good fluidity during the test welding, and the weld bead is bright.

[0033] ③ The aluminum alloy die-casting 2 is suitable for welding with small current and slow welding speed. Use any one of the positive circle swing or the oval circle swing. The circle swing can fully stir the molten pool and facilitate the precipitation of gas in the molten pool.

[0034] S3. Processing dimensions of the welding groove of the aluminum alloy die-casting,

[0035] ① Open a first single V-groove at one end of the aluminum alloy profile 1 close to the aluminum alloy die-casting 2, and open a second single V-groove at one end of the aluminum alloy die-casting 2 close to the aluminum alloy profile 1. The blunt edge is 1 mm, the assembly gap is 0 mm, and the groove angle after the assembly of the first single V-groove and the second single V-groove is 60°. This solves the technical defects that too small groove angle, too large blunt edge, too small gap, etc. in the prior art will affect the penetration during welding and cause lack of fusion or lack of penetration.

[0036] ② Within 20 mm on both sides of the front and back of the weld bead, use a wire brush to remove the oxide film.

[0037] S4. Set values of the welding process for the aluminum alloy die-casting and the aluminum alloy profile,

[0038] Welding method; MIG welding function of the robot-equipped welding machine;

[0039] Welding curve; Pulse GMAW universal 1 / 1 3555;

[0040] Welding wire grade; 4043, diameter is ϕ1.2 mm;

[0041] Welding shielding gas: pure argon, and the gas flow rate of pure argon is 22 L / min. The present invention adopts surface cleaning before welding, which solves the technical defects of the prior art that there is residual mold release agent on the external surface of aluminum alloy die-castings, and slag inclusions, near-surface pores, and near-surface cracks are likely to occur during welding; by analyzing the weldability of the aluminum alloy die-casting material, it solves the technical defects of the prior art that the internal organizational structure of aluminum alloy die-castings is loose, easy to absorb moisture, and internal pores and internal cracks are likely to occur due to thermal expansion during welding; it solves the technical defects of the prior art that the internal structure of aluminum alloy die-castings contains impurities and internal slag inclusions and internal cracks are likely to occur during welding; the processing dimensions of the groove of the aluminum alloy die-casting are mainly single-sided trumpet-shaped and single-V butt welds, which solves the technical defects of the prior art that too small groove angle, too large root face, too small gap, etc. will affect the penetration during welding, resulting in lack of fusion or lack of penetration; the method for setting the welding process of aluminum alloy die-castings and aluminum alloy profiles solves the technical defects of the prior art that improper selection of welding parameters, such as too large welding current and too fast welding speed, will cause the weld to overheat, generate large thermal stress, and thus lead to crack generation.

[0042] Example 2: On the basis of Example 1, in step S1, before welding the aluminum alloy die-casting 2, the surface mold release agent is removed by any one of hot water cleaning, or ultrasonic cleaning, or surface sandblasting. The present invention adopts removing the surface mold release agent of the aluminum alloy die-casting before welding, which solves the technical defect of incomplete cleaning before welding of the aluminum alloy die-casting in the prior art.

[0043] Example 3: On the basis of Example 1, referring to Figure 3 , in step S2, the thicknesses of both the aluminum alloy profile 1 and the aluminum alloy die-casting 2 are 3 mm, and a positive circle is swung counterclockwise without staying at both sides of the groove, and the trajectories of each circle overlap by 2 / 3. The present invention adopts the method of swinging a positive circle without staying at both sides of the groove and the trajectories of each circle overlapping by 2 / 3. The positive circle swing can fully stir the molten pool and facilitate the precipitation of gas in the molten pool.

[0044] The above is only the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for welding die castings and profiles of aluminum alloy battery trays for new energy vehicles, comprising the following steps: S1. Surface cleaning before welding, Before welding, the surface release agent of the aluminum alloy die casting (2) is removed, and the surface of the aluminum alloy die casting (2) is cleaned; S2. Analysis of weldability of aluminum alloy die castings. ① The material of the aluminum alloy die casting (2) is CMM.ALSi10MnMg.F; the material of the aluminum alloy profile (1) is 6061, and argon arc welding is used to autogenously weld the aluminum alloy die casting (2) without filling wire; ② Aluminum alloy die castings (2) Welding judgment: the judgment method is that there are no obvious pores on the weld surface, the solution has good fluidity during the test welding, and the weld is bright; ③ Aluminum alloy die castings (2) Welding is suitable for small current, slow welding speed, and either positive circle swing or elliptical circle swing; S3. Processing dimensions of grooves for welding aluminum alloy die castings, ① A first single V-shaped groove is formed at one end of the aluminum alloy profile (1) close to the aluminum alloy die casting (2), and a second single V-shaped groove is formed at one end of the aluminum alloy die casting (2) close to the aluminum alloy profile (1), the blunt edge is 1 mm, the assembly gap is 0 mm, and the groove angle of the first single V-shaped groove and the second single V-shaped groove after assembly is 60°; ② Use a wire brush to remove the oxide film within 20mm on both sides of the weld; S4. Setting value of welding process between aluminum alloy die casting and aluminum alloy profile, Welding method; MIG welding function of robot welding machine; Welding curve; pulse GMAW universal 1 / 1 3555; Welding wire brand; 4043, diameter φ1.2mm; Welding shielding gas: pure argon gas, the gas flow rate of pure argon gas is 22L / min.

2. A method for welding die castings and profiles of aluminum alloy battery trays for new energy vehicles according to claim 1, characterized in that: In the step S1, the surface release agent of the aluminum alloy die casting (2) is removed before welding, and any one of hot water cleaning, ultrasonic cleaning, or surface sandblasting is used.

3. The method for welding die castings and profiles of aluminum alloy battery trays for new energy vehicles according to claim 1 is characterized in that: In step S2, the thickness of the aluminum alloy profile (1) and the aluminum alloy die-casting (2) are both 3 mm, and a positive circle swing is adopted, swinging to both sides of the groove without stopping, and each circle trajectory overlaps 2 / 3.

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