Effect of shot peening on carburised surfaces

The aim of this work is to examine the residual stress distribution in carburized steel components subjected to shot peening. A numerical model of the shot peening was developed by means of the ABAQUS explicit code, taking into account the variation in the material mechanical properties from the surface towards the core, defined on the base of the microhardness profile experimentally measured. The rate dependent hardening of the material was also considered for these analyses, together with the softening due to the heat generation during the impact. The model was verified by experimental residual stress measurements carried out on disk specimens, carburized and shot peened as in a typical industrial application. The analyses, repeated for different values of shot velocity and dimensions, show the influence of these parameters and that of the carburizing depth on the final residual stress distribution.