Effect of substrate orientation and anisotropic strength on corrosion pits

The complexities of pitting corrosion and its associated pit morphologies are critical for predicting and preventing pit-related failure in materials. With the advances in computational tools, modeling of pitting corrosion has lately gained momentum. We recently developed a phase field model for 3-D pit morphology, and in the current work, the model is utilized to gain insight into the role of substrate orientation and anisotropic strength on crystallographic pits. The influence of these parameters on pit morphology and corrosion metrics such as pit volume, current, pit area, current density, and pit depth are studied. The crystallographic pit morphology changes with substrate orientation but not significantly with anisotropic strength. The anisotropic strength strongly influences the corrosion metrics whereas most corrosion metrics remain unaffected by substrate orientation. • 3D Crystallographic pit morphology is simulated employing phase field modeling • Substate orientation affects pit morphology but does not affect corrosion metrics • Anisotropic strength has greater impact on corrosion metrics • Corrosion of anisotropic material is controlled by the slowest corroding planes.