Influence of high frequency induction heat treatment on residual stress in 2219 aluminum alloy TIG welded joint

The tungsten inert gas(TIG) welding was used to weld 8 mm-thick 2219 aluminum alloy, the high frequency induction heat treatment was carried out to welded joint at 90 ℃,140 ℃ and 190 ℃, respectively, and X ray diffraction method was used to measure welding residual stress before and after heat treatment, then microstructure and mechanical properties were analyzed. The results showed that effects of heat treatment on welding residual stress at 140 ℃ and 190 ℃ are significant, while that at 90 ℃ is relatively poor. Compared with the samples without heat treatment, no obvious change is observed in microstructure, tensile properties and distribution of hardness of welded joint.