A comprehensive modelling and experimental approach to study the diffusion-controlled dissolution in pitting corrosion
By Nguyen, Van Anh; Newman, Roger C.
Published in Corrosion Science
2021
Abstract
The novelty of this paper is that we consider the “diffusion-controlled” dissolution of a metal in a pit from a more advanced point of view, such that the limiting anodic current density (iL) varies with the bulk NaCl concentration in accordance with a mathematical model that includes ion migration. The full mass transport model was coupled with artificial pit experiments to obtain critical parameters for pit stability. At above 2.5 M NaCl, the conventional diffusion-only model gives reasonably accurate results, but the effect of Na+ at the bottom of the pit on iL and the metal’s solubility should be considered.