Crystallography of Stress corrosion cracking of austenitic stainless steel by scanning electron microscope and electron backscatter diffraction

Abstract

In this study, Stress Corrosion Cracking (SCC) produced for 304L austenitic stainless steel in different concentrations of chloride containing sulfuric acid solutions was analyzed using both Scanning Electron Microscope (SEM), and Electron Backscatter Diffraction (EBSD). X-Ray Diffraction (XRD) was used to analyze the residual-applied stresses before and after cracking. Crack observation using SEM revealed clear traces of successive slipping planes and consequent dissolutions on the facets of the obtained cracks. Moreover, ruptured grains were analyzed for their orientation using EBSD technique. Analysis disclosed two preferential rupture planes; {110}, {111} with percentage of 48% and 37% respectively. After cracking, XRD stress profile analysis showed a gradual stress relaxation through sample’s depth from the applied stress in the bulk of the material to the inherent residual stress attributed to fabrication processes in the zone where the cracks are present.