以水为透明约束层，采用调Q(脉冲高峰值功率)的YAG激光对A6061-T6铝合金熔化极惰性气体保护焊接接头焊趾附近进行了激光冲击强化，并对比研究了A6061-T6铝合金焊接接头在激光冲击强化与焊态下的性能。试验结果表明，激光冲击强化的铝合金焊接接头与焊态下的相比，其冲击强化区的维氏硬度得到明显提高，焊接接头疲劳寿命得到较大幅提升；焊态下的试样疲劳断口位于焊缝或焊缝近旁，激光冲击强化下的试样疲劳断口位于基体金属上；激光冲击强化后在材料近表面获得了较大的残余压应力，其最大值约为-145 MPa；与基体金属相比，激光冲击强化后的表面粗糙度增大。

In the present work, laser shock processing (LSP) using a Q-switch YAG laser facility with high pulsed peak power under water environment is implemented near the toes of A6061-T6 Aluminum alloy metal-inert gas (MIG) welded joints. And the properties of A6061-T6 aluminum alloy MIG welded joints is analyzed before and after laser shock processing through the comparative method. The results show that after laser shock processing, Vickers hardness and fatigue life of the welded joints have been significantly improved, fatigue fracture of the welded joint without laser shock processing is located in or near the welded while it is located on the base material after laser shock processing, and a larger near-surface residual compressive stress with a maximum value of about -145 MPa is obtained. Compared with the base material, the surface roughness deteriorates after laser shock processing.