Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates (50 mm thick) by using finite element and contour measurement methods. A three-dimensional finite element model of 50-mm-thick titanium component was proposed, in which a column-cone combined heat source model was used to simulate the temperature field and a thermo-elastic-plastic model to analyze residual stress in a weld joint based on ABAQUS software. Considering the uncertainty of welding simulation, the computation was calibrated by experimental data of contour measurement method. Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint. The peak tensile stress exceeds the yield strength of base materials inside weld, which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.