Three Dimensional Weld Residual Stresses Simulations of Start/Stop and Weld Repair Effects

Weld Residual Stresses are a major concern as they markedly reduce reliability. Accurate prediction is therefore essential and is usually carried out by mean of Finite Element Analysis. In many cases, two dimensional axisymmetric modelling is sufficient but comparison with measurement has shown limitations. Full 3D simulations are therefore now preferred in several applications and especially when it comes to studying start/stop and (partial) repair effects. These two events have here been simulated in 3D and comparison with 2D results indicate a significant increase in Weld Residual Stresses. As an illustration, the reduction on critical crack size is assessed by a Fracture Mechanics analysis.