Modeling the influence of microstructure on the stress distributions of corrosion pits

•Varying initial pit location in microstructure leads to geometric variability.•Total pit curvature displays a modest correlation with maximum principal stress.•Microstructure significantly impacts local quantities (maximum principal stress).•Microstructural effect on global measures (stress intensity factor) less pronounced. This work explores how microstructure influences stress distributions around corrosion pits through computational modeling that captures crystallographic orientation dependencies in corrosion potential and mechanical response. Several sites are considered for initial corrosion pits to investigate the resultant variation in pit geometry and stress quantities. Comparisons to a homogeneous, semi-circular model show that microstructure-sensitive cases can have much larger maximum stress magnitudes, but the stress intensity factors from the homogeneous case are quite congruous to those from the microstructure-sensitive cases. This study illustrates how microstructure impacts local quantities, whereas global quantities are more consistent and comparable to a fully homogeneous assumption.