Study of Dual Pre-stress Method on Controlling Welding Deflection Deformation of Aluminum Alloy Thin Plate

摘要

The development of a new method which control welding distortion and hot crack, the dual pre-stress method, and its application to LY12 (2024Al) are described. This method supply the elimination of side-effects for the conventional single-pre-tensile stress that causes hot–crack during welding, especially at the starting of the welding. In testing, the contribution for controlling welding reflection distortion by transverse pre-stress of dual pre-stress was found. The numerical simulation concentrated on the maximum residual stress in comparison between regular welding and in dual pre-stress welding occasions. The results shows that the welding deflection distortion decreased gradually with the pre-stress value increasing. For given pre-stress value of 0.3σs,0.5σs,0.7σs in longitudinal direction (σs is yield stress of aluminum，320MPa ) and 0.5σs(longitudinal)+0.1σs(transverse), the maximum deflection magnitude were 9mm,5mm,1mm respectively.