Laser tailor-welding method for heterogeneous different-thickness plates

Abstract

The invention discloses a laser tailor-welding method for heterogeneous different-thickness plates. The method comprises the steps that (1) tailor-welded surfaces of a thick plate and a thin plate which need to be tailor-welded are determined, and the tailor-welded sides of the two tailor-welded plates are accurately cut; after accurate cutting, the gap between the two plates in the butt joint process is smaller than or equal to 10% of the plate thickness of the tailor-welded side of the thick plate; (2) the surfaces of the two tailor-welded plates subjected to fine cutting are cleaned, and then the fine cutting edges of the two tailor-welded plates are butted; and (3) laser beams of laser welding equipment are adopted for welding the tailor-welded plates, the power of the laser beams ranges from 3000 W to 4000 W, the offset of the laser spot position in the thick plate direction ranges from 0.12 mm to 0.18 mm, the welding speed ranges from 3 m / min to 7 m / min, the defocusing amount is set to range from -0.5 mm to + 1.4 mm, and inert gas is adopted as protective gas in the welding process. The laser tailor-welding method can prevent the defect of weld joint cracking caused by uneven butt joint of the tailor-welded surfaces; the method has the characteristics of high efficiency, controllability, high straightness of butt-joint tailor-welded surfaces, small difference in joint performance and high laser tailor-welding quality.

Description

technical field [0001] The invention relates to a laser welding method, in particular to a laser tailor welding method for heterogeneous and different thickness plates. Background technique [0002] With the development of science and technology, the automotive industry pays more and more attention to reducing weight and energy consumption, especially with the increasingly stringent emission standards and the increasing demand of users for the mileage of new energy vehicles, the lightweight of the whole vehicle has become The main focus of OEMs. Lightweight structures and lightweight materials are essential technical paths for lightweight vehicles. Tailored welded blanks can be combined with the functional requirements of auto parts to customize the connection of differential strength, differential thickness, and heterogeneous metal sheets to achieve component design upgrades and material optimization. [0003] At present, more and more materials have realized the producti...

AI Technical Summary

Problems solved by technology

However, due to differences in thickness, strength and properties, heterogeneous and poorly thick materials have large differences in mechanical properties, composition, etc., especially after experiencing laser welding thermal cycles, resulting in differences in weld joint performance, which directly affects subsequent products. Forming quality

The current welding method has defects such as weld cracking defects and poor performance of welded joints caused by plate thickness differences, which have not been effectively resolved so far.

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