Elucidating the grain-orientation dependent corrosion rates of austenitic stainless steels

The dependence of oxidation rates on grain orientation has been observed for austenitic alloys suggesting crystallographic control of such processes. To better understand these observations, the active and transpassive oxidation behaviors of an austenitic AISI 316L stainless steel were investigated using vertical scanning interferometry (VSI). The oxidation rates of >100 unique grains were measured and related to their crystallographic orientations (i.e., with respect to the surface normal direction) as identified using electron backscatter diffraction (EBSD). The oxidation rates follow a scaling that is given by: {001}