Performance analysis on welded joints made of TC4/TA17 dissimilar titanium alloys

Application of dissimilar titanium alloys is an effective manufacturing approach of large-scale underwater equipment for reducing costs and increasing efficiency while welding processes require extensive research. In the present study, the properties of butt welding model and T-joint model made of TC4/TA17 dissimilar titanium alloys are investigated including the temperature field, stress field and deformation. The residual stresses and deformation are compared with the experimental results by extracting date from different paths. The numerical simulation results are mostly consistent with the experimental data. Results show that the peak values of residual stresses in both models approaches to the yield stress of TC4. And when TC4 is applied as welding wire material comparing to TA17 in butt welding, the residual stresses are well distributed and the maximum stress after welding occurs near the junction of the two materials. In the T-joint, the simulation results of deformation are validated by experiments. The deformation of the flange is upturned on both sides and the peak area of longitudinal stress generated at the weld is slightly larger. Residual stress distributions are provided as a reference for actual structure welding and subsequent heat treatment processes.