Resistance spot welding process for aluminium alloy parts

Abstract

The invention relates to the technical field of metal welding, and discloses a resistance spot welding process for aluminium alloy parts, which includes the following steps: (S1) parts to be welded are flattened in order to adjust the flatness of the parts to be welded; (S2) the parts to be welded are spot-welded, which includes the following steps: (S10) initial pressure is applied, so that the welding spots of the parts to be welded are in tight contact; (S20) a spot-welding machine is connected with welding current to preheat the welding spots of the parts to be welded; (S30) the welding current is increased to heat and weld the preheated parts to be welded, so that the welding spots of the parts are melted; (S40) the welding current is decreased to post-heat the parts; (S4) the spot-welding machine is disconnected from the welding current, and pressure is kept on the parts for a period of time, so that the welding spots are formed into nuggets. The welding process can reduce welding deformation, ensure the quality of the welding spots and prevent the phenomenon of welding spot cracking, thus increasing the quality of products, dispensing with the process of intermittent welding, saving manpower and material resources and increasing the efficiency of production.

Description

technical field [0001] The invention relates to the technical field of metal welding, in particular to a resistance spot welding process for aluminum alloy parts. Background technique [0002] Compared with other metals, aluminum alloys have the advantages of low density, high specific strength, good mechanical properties and process characteristics, etc., especially medium-strength aluminum alloys have been widely used in the production of aluminum alloy car bodies for rail vehicles. However, the linear expansion coefficient of aluminum alloy is large, and the deformation and crack tendency of the weldment are also relatively large. Therefore, corresponding effective measures need to be taken during welding to ensure the welding quality. [0003] Weld cracking is one of the most common problems in the manufacture of welded structures. In the welding production process of the aluminum alloy end wall of the subway, cracking of the solder joints often occurs, and a card can b...

AI Technical Summary

Problems solved by technology

This cracking phenomenon has always existed since the trial production of the product, and has a great impact on product quality and production

At present, in order to solve the above solder joint cracking problem, intermittent welding is generally used to replace the cracked spot welding. Tighten the intermittent welding position and perform intermittent welding. After welding, it needs to be polished again and leveled. Therefore, it takes a lot of manpower and material resources, which seriously affects the production efficiency.

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