Influence of the target material constitutive model on the numerical simulation of a shot peening process

The aim of this study is to analyse the effect of the constitutive material model used to describe the target material on the results obtained from numerical modelling of a shot peening process. After a comprehensive experimental characterization of a duplex stainless steel, including both high rate monotonic tests and low cyclic fatigue tests, three constitutive models are proposed and incorporated into a finite element simulation. The goodness of each constitutive model is analysed by comparing the numerical predictions of residual stress and roughness with the experimental findings. The best results were obtained using a non-linear kinematic–isotropic model which combines the effect of the cyclic deformation produced by repeated impacts with the strain rate effect through its isotropic component. If we consider only the effect of the strain rate, the numerical predictions overestimate the experimental values of residual stress. If instead we only take into account the cyclic loading effect, the numerical predictions underestimate the actual residual stress values.