Laser welding T-joint weld seam shape improving method

Abstract

The invention provides a laser welding T-joint weld seam shape improving method. The laser welding T-joint weld seam shape improving method comprises the steps that oil contamination, surface oxides and metal vapor residual pollutants of a weld seam and a weld toe portion of a T-joint are cleaned away; the T-joint to be modified is fixed to a welding fixture, the weld seam and the weld toe portionof the T-joint are remelted and modified simultaneously by using defocusing double-laser beams, and the shapes of the weld seam and the weld toe are improved; and a workpiece is removed from the welding fixture after the weld seam and the weld toe of the T-joint are completely cooled. According to the laser welding T-joint weld seam shape improving method, accessibility of the laser beams is good, the spot diameter is small, and remelting and modification of the laser welding T-joint weld seam and weld toe can be accurately realized; the welding process is stable, and heat input is low; the quality of the modified weld seam is good and the joint deformation is small; and the welding speed is high, the degree of automation is high, additional equipment and personnel are not needed, original laser equipment is only needed, the production cost can be saved, and production and economic efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of laser processing, in particular to a method for improving the shape of a laser welding T-shaped joint. Background technique [0002] In recent years, the integrated structure has become the focus of structural design development in the development of lightweight weapons and equipment. Due to the light weight of aircraft fuselage panels, a large number of thin-walled and reinforced structures are required. Due to the characteristics of high energy density, low heat input, fast welding speed, small welding deformation, no need for vacuum, and easy automatic welding of complex curve welds, laser welding technology has become a light-weight method for connecting T-joints of aircraft thin-walled ribbed structures. quality and efficient manufacturing methods. [0003] However, there is an obvious cross-sectional mutation at the transition between the weld seam and the base metal of the laser-welded T-joint, t...

AI Technical Summary

Problems solved by technology

For this type of joint, due to the limitation of the joint form and weld size, the traditional method of improving fatigue performance is difficult to implement and the process accessibility is poor

The method of machining and grinding the weld seam is difficult to guarantee the stability and consistency of the process, and the grinding is easy to affect the quality of the weld seam formation, resulting in uneven weld seam formation

Especially for double-beam welded T-joints with extremely narrow weld seams, the grinding process is difficult to achieve

Due to the extremely narrow weld seam, the accessibility of the TIG modified welding process for laser welded T-joints is poor, and the modification process is also difficult to achieve, and the TIG modified welding seam is wide and the heat-affected zone is large, which is easy to cause a large weld out of shape

In addition, additional equipment and personnel are required for both grinding and TIG finishing welding, which increases production costs to a certain extent

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