Welding process for automobile connecting rod assembly

Abstract

The invention provides a welding process for an automobile connecting rod assembly, the automobile connecting rod assembly includes a connecting rod and a ball pin sleeve, the connecting rod and the ball pin sleeve are fixedly connected by welding, and the After the connecting rod and the ball pin sleeve are welded, the welded part is subjected to heat preservation treatment for a certain period of time. The present invention reduces the carbon content of the weld seam formed after welding by performing heat preservation treatment on the welded part for a certain period of time, and avoids the hardened structure (martensitic structure) which is very sensitive to cold cracks when the welded part is quickly cooled. ), it can also avoid the problem of embrittlement of the overheated zone due to the formation of hard and brittle high-carbon martensite when the cooling rate is large, and it is beneficial to the removal of hydrogen from the weld, thereby reducing the post-weld welding The risk of hydrogen embrittlement in seams can be reduced, which is conducive to improving the welding quality of automotive connecting rod assembly products and improving the service life of automotive connecting rod assembly products.

Description

technical field [0001] The invention relates to the technical field of welding of an automobile connecting rod assembly, in particular to a welding process of an automobile connecting rod assembly. Background technique [0002] The existing automobile connecting rod assembly usually includes a connecting rod and a ball pin sleeve. The connecting rod and the ball pin sleeve are usually welded to form a fixed connection. During the welding process, since there is a welding end of the connecting rod The chamfered boss, therefore, during the spot welding process, the boss material is compressed to form a hemispherical weld instead of a circular arc transition weld, resulting in a decrease in the fatigue performance of the weld; and, due to the existing automobile connecting rod The connecting rods in the assembly are mostly made of 40Cr, which has a high carbon content, and the ball pin bushings are mostly made of 20# material, which is rapidly cooled in the air after welding, w...

AI Technical Summary

Problems solved by technology

[0002] The existing automobile connecting rod assembly usually includes a connecting rod and a ball pin sleeve. The connecting rod and the ball pin sleeve are usually welded to form a fixed connection. During the welding process, since there is a welding end of the connecting rod The chamfered boss, therefore, during the spot welding process, the boss material is compressed to form a hemispherical weld instead of a circular arc transition weld, resulting in a decrease in the fatigue performance of the weld; and, due to the existing automobile connecting rod The connecting rods in the assembly are mostly made of 40Cr, which has a high carbon content, and the ball pin bushings are mostly made of 20# material, which is rapidly cooled in the air after welding, which will easily cause cracks during rapid cooling. The hardened structure (martensitic structure) that is very sensitive to cold cracks. At the same time, when the cooling rate is large in the superheated zone, it is easy to form hard and brittle high-carbon martensite, which makes the superheated zone brittle and increases Risk of hydrogen embrittlement in welds

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