Abstract
In the present study, the detailed welding distortion of bead welded plates under temporary tacking state and released state was predicted by thermal elastic-plastic finite element model (FEM) and also measured by the digital image correlation (DIC) method. It was found that the residual welding angular distortion can be reduced to about 50–60% by temporary tacking, while the residual transverse shrinkage and longitudinal shrinkage are less affected. Further, the welding distortion with different ratios of temporary tacking length to weld length for various dimensions of bead welded plates was quantitatively investigated by FEM. The inherent deformations which are described by the integrated values of residual plastic strains were proved to be the same before and after releasing the temporary tacking. The effect of temporary tacking on the welding distortion and inherent deformation were analysed in details.