Predicting the corrosion-wear response of an isolated austenite phase under anodic polarization

The wear-assisted corrosion response of a super-duplex stainless-steel from a single asperity contact was obtained using atomic force microscopy (AFM). The AFM tip applied increasing loads to an isolated surface region that was polarized to two different static potentials in the passive potential region of the alloy in a 0.6 M NaCl solution. The wear-assisted corrosion response was modeled using an interfacial film growth model to obtain consistent kinetics parameters for the austenite phase response across applied loads and polarization potentials. The average response was then fit with an Arrhenius model that suggested that the stress fields from the single asperity contact induced damage in the protective oxide but also disrupted other oxide-formation processes at the oxide-electrolyte interface, thereby slowing repassivation, and allowing increasingly high corrosion currents as the stress fields increased.