Effect of boundary conditions on residual stress and distortion in T-joint welds

Abstract

This study investigates the welding residual stress and distortion in T-joint welds under various mechanical boundary conditions. An experimentally calibrated and sequentially coupled thermal and mechanical 3D finite element (FE) model is developed, and Goldak's double ellipsoidal heat source model is implemented into the numerical model. The results show that the transverse residual stress, vertical displacement, angular distortion and transverse shrinkage depend significantly on the mechanical boundary conditions, and the influence on the longitudinal residual stress is not significant. Applying the clamped condition along the edges during the welding process and releasing it after the T-joint cools down to ambient temperature can significantly reduce the welding-induced geometric imperfections.