An Analysis of Limiting Cases for the Metal Oxide Film Growth Kinetics Using an Oxygen Defects Model Accounting for Transport and Interfacial Reactions

Abstract

Abstract This work was motivated by the need to understand the passivation of metal surfaces to provide resistance against chemical degradation, given that corrosion is a major limiting factor in the operational lifetime of metals and their alloys. In this study, a unified analysis for an oxide growth model was presented. The oxide growth model was consistent with the literature and accounted for the transport of oxygen defects through a growing oxide film, as well as the electrochemical reactions of oxygen defects at the metal/oxide and oxide/environment interfaces. A linear potential profile across the oxide film was assumed. The model was analyzed for different rate limiting steps in the physicochemical process and perturbation techniques were utilized when necessary. The investigation yielded the well-known linear, parabolic, logarithmic and integral rate laws and the conditions that led to these rate laws were discussed.