DefinePK

Abstract

This paper presents the mathematical model of the propagation of pitting corrosion using a commercial finite element program, COMSOL Multiphysics. In view of the chemical and electrochemical reactions inside a single pit in steel, a two dimensional model that allows the prediction of pit evolution is developed. The model is solved under the Nernst-Planck resolution. The results show that different sites of the geometry give different current densities and different concentrations of ionic species. In addition, the pH inside the corroding pit is also shown to reduce gradually as hydrogen ions gradually accumulate inside the pit, an occurrence expected in pitting behavior.