Peridynamic Modeling of Repassivation in Pitting Corrosion of Stainless Steel

This article introduces repassivation and salt film formation models in a peridynamic formulation for corrosion damage. The model leads to autonomous generation of lacy covers in pitting corrosion and development of secondary pits. It does not require interface conditions. The electrical current density, usually provided as an input into the problem, is obtained as part of the solution procedure. Validation against available 2D experimental results on pitting corrosion shows the model to be predictive in terms of corrosion rate and pit shape evolution in time. The influence of electrolyte potential drop, applied potential, and chloride concentration on the pit shape, corrosion rate, and the lacy cover structure are studied. Results agree well with experimental observations.