Simulations of film growth and diffusion during the corrosion process

A simple model is proposed to describe some general aspects concerning the formation of films at metal\ionic solution interfaces. Working on a mesosco pic scale, three main processes are retained: the metal corrosion, the redu ction of one species present in the ionic solution and the diffusion of one species from the corrosion front to the growth front where the reduction t akes place. This model differs from those devoted to the growth on a surfac e by the existence of two fronts and their coupling. Moreover, a coupling b etween the diffusive species is taken into account. To emphasize the role o f the diffusion, the predictions of the model are compared with those obtai ned from a simple extension of the Eden model. Due to diffusion a dissymetr y is created between the two fronts which obeys different scaling laws. The internal structure of the film during its formation is investigated via th e concentration of diffusive species. (C) 2001 Elsevier Science B.V. All ri ghts reserved.