Modeling fretting-corrosion wear of 316L SS against poly(methyl methacrylate) with the Point Defect Model: Fundamental theory, assessment, and outlook

This work aims at investigating experimentally fretting corrosion, that is, corrosion induced by friction of AISI 316L SS against poly(methyl methacrylate) under small displacements, and subsequently using the data to model wear. The observed wear on the stainless steel has been modeled using the Point Defect Model (PDM). The originality of this approach in applying the PDM to fretting corrosion consists of using a modified rate of the barrier layer dissolution, in the case of cyclical wear, such that the rate of destruction of the barrier layer at the barrier layer/solution interface exceeds the rate of barrier layer growth at the metal/barrier layer interface at zero barrier layer thickness, which is the condition specified by the PDM for depassivation. By optimization of the PDM on experimental electrochemical impedance data under fretting conditions, we have been able to ascertain values for various model parameters, and to calculate the steel volume loss as a function of potential.