Analysis and presenting an optimum post weld heat treatment cycle to maximum reduction of residual stresses of electron beam welding

In this research, the electron beam welding process of P91 steel plates was simulated by the finite element method in two dimensions and in a short time with acceptable accuracy in two steps (non-coupled thermal and mechanical analysis). The simulation results were validated with experimental and numerical results presented by other researchers. Moreover, by applying post weld heat treatment, the residual stresses were reduced. Then, the effect of heat treatment cycle parameters such as heat input power, heating time, holding time and cooling rate were investigated on the quantity of residual stress reduction. By examining the results of the effects of the parameters, an optimum heat treatment cycle is introduced to maximum reduction of the residual stress. Using this optimum heat treatment cycle, the residual stress value was reduced to 55 percent.