Modelisation of mechanical behavior of a grade 12% Cr steel coating material

Several isothermal mechanical tests were performed on a stainless steel to determine the parameters of a viscoplastic behavior law in the range (20–700°C). The parameters were identified by means of a systematic numerical procedure (a computer program of simulation and identification). The microstructural evolution, during mechanical tests, was examined and related to the evolution of internal variables of the viscoplastic model. It was found that at every temperature the material shows cyclic softening behavior. Moreover, at 450°C a high stress level was correlated with the microstructural evolution of the material and the increase of the kinematic variable of the model.