Electro-chemo-mechanical phase field modeling of localized corrosion: theory and COMSOL implementation

A new theoretical phase field-based formulation for predicting electro-chemo-mechanical corrosion in metals is presented. The model combines electrolyte and interface electrochemical behaviour with a phase field description of mechanically-assisted corrosion accounting for film rupture, dissolution and repassivation. The theoretical framework is numerically implemented in the finite element package COMSOL MULTIPHYSICS and the resulting model is made freely available. Several numerical experiments are conducted showing that the corrosion predictions by the model naturally capture the influence of varying electrostatic potential and electrolyte concentrations, as well as predicting the sensitivity to the pit geometry and the strength of the passivation film.

Automated summary

A new theoretical model based on phase field theory is proposed for predicting electro-chemo-mechanical corrosion in metals. The model combines electrolyte and interface electrochemical behavior with a phase field description of mechanically-assisted corrosion, including film rupture, dissolution, and repassivation. The theoretical framework is numerically implemented and freely available. Numerical experiments demonstrate that the model can accurately capture the influence of electrostatic potential, electrolyte concentrations, pit geometry, and passivation film strength on corrosion predictions.