Finite element simulation of the residual stress in Ti6Al4V titanium alloy laser welded joint

Abstract

Abstract In this study, in order to investigate the mechanical heterogeneity of a Ti6Al4V titanium alloy laser-welded joint, microstructural examinations, microhardness tests and shear punch tests were carried out. Meanwhile, hole drilling was deployed to measure the residual stress in the joints. In residual stress simulation studies, the complex phenomenon of welding was numerically modelled by indirectly coupled transient, non-linear thermo-mechanical analysis. An elongated combined heat source was used here for modelling the temperature field. The effects of the residual stress after welding, both for considering and neglecting mechanical heterogeneity, were investigated systematically. The obtained results indicate that the residual stress of the simulation, when mechanical heterogeneity is considered closely, matches the experimental data.