Performance of shock processing on aluminum alloy welded joint

In order to improve the mechanical properties of aluminum alloy welded joints, this paper respectively applied ultrasonic and Q-switch YAG laser shock processing on the weld toe of A6061-T6 aluminum alloy welded joints to study the performances of aluminum alloy welded joints after shock processing. Under two shock processing modes, the near surface on weld toe of aluminum alloy welded joints generated shock strengthening effect,and greater compressive residual stress was produced. The maximum compressive residual stresses generated by ultrasonic and laser shock processing were about -158 MPa and -145 MPa, respectively. The fatigue life of aluminum alloy welded joints after ultrasonic and laser shock processing was similar, increased more than one time compared to that of the welded specimen without shock processing. All specimens during fatigue test fractured in the base metal, and no fatigue crack occurred near the weld toe.