Numerical simulation of dealloying by surface dissolution via the evolving surface finite element method

In this article we formulate a numerical method for the simulation of dealloying of a binary alloy by the selective removal of one component via electrochemical dissolution such that there is phase separation of the other component at the solid/electrolyte interface. The evolution of the interface is modelled by a forced mean curvature flow strongly coupled to the solution of a Cahn-Hilliard equation modelling surface phase separation. The method is based on a triangulated hypersurface whose evolution is calculated as well as the solution of the Cahn-Hilliard equation by the evolving surface finite element method (ESFEM). The numerical experiments simulate complex morphology and concentration patterns providing evidence that the mathematical model may describe the formation of nanoporosity.