Investigations on the changed intensity shot peening specimens machined from SS304: process characterization, fatigue modeling, and failure analyses

Abstract

Characterization on the surface morphology, residual stress relaxation and fatigue life prediction of the changed intensity shot peening specimens machined from SS304 were carried out. The present work aims, first and foremost, to model the fatigue performance of shot peening specimens machined from SS304 in extra-low-, low-and high-cycle regime by clarifying the relaxation life component and fatigue life component with the total failure life, thereby successfully evaluating the fatigue performance of un-/0.1 mmA-/0.25 mmA-/0.4 mmA-peened components with satisfactory results in the whole cycle regime. It is, therefore, essential to provide a precise definition of the master life diagram on the purpose of evaluating the fatigue performance of shot peening components in service by linear interpolation of shot peening intensities considering the engineering applicability. Additionally, the characterization of multiple-fatigue crack initiation to failure was also identified by fractography analysis, which reasonably illustrated the non-conservative life prediction in the high-cycle regime.