AN EXPERIMENTAL-STUDY OF THE QUASI-2-DIMENSIONAL CORROSION OF ALUMINUM FOILS AND A COMPARISON WITH 2-DIMENSIONAL COMPUTER-SIMULATIONS

The propagation of a (1 + 1)-dimensional corrosion front into a quasi- two-dimensional aluminum foil confined in an electrochemically inert t hin cell was studied experimentally. The corrosion experiments were ca rried out under controlled electrochemical and flow conditions leading to corrosion fronts consisting of isolated and coalesced pits. The ge ometry of digitized images of these disorderly corrosion fronts was an alyzed quantitatively. A two-dimensional computer model that includes passivation and depassivation processes was used to simulate the corro sion fronts and the simulated fronts were compared quantitatively and qualitatively with the experimental results. Unlike earlier passivatio n/depassivation models, this model includes the increasing electrolyte concentration in corrosion pits during the corrosion process, leading to the development of a more corrosive environment in the pits.