Forecasting interface roughness from kinetic parameters of corrosion mechanisms

This paper is aimed at investigating the possibility of predicting interface roughness behavior from reaction kinetic parameters of a simple open-circuit potential corrosion mechanism. A cellular automaton algorithm simulates the evolution of a dissolving metallic front according to specific rules that govern transitions between the different states associated with surface reactants. A first mathematical model presents a rigorous mesoscopic treatment incorporating kinetic parameters and purely morphologic descriptors and yields an analytical expression accounting for the interplay between reaction kinetics and morphology. Comparing the mean cell-lifetimes of active species taking part in the model does this. A new morphological descriptor built on reaction kinetic parameters is introduced and shown to represent the interface roughness very well. Finally, a simplified version of the model, which resorts to the exclusive use of measurable electrochemical quantities, is proposed. Results are promising, showing the approach to be an interesting tool for the understanding and even forecasting of the complex interaction between reaction kinetic parameters and morphological features of metal ∣ electrolyte interfaces.