Mechanistic Corrosion Modeling: Application of the MSE Corrosion Framework to Corrosion Resistant Alloys

Abstract Accurate prediction of corrosion behavior in chemically diverse environments is critical for material selection, process reliability, and asset longevity. To address this need, this study presents the application of the Mixed-Solvent Electrolyte (MSE) thermodynamic framework, integrated with an electrochemical corrosion model, to predict the general corrosion behavior of three corrosion-resistant alloys: UNS S31600 (316 stainless steel), UNS N06625 (alloy 625), and commercially pure titanium. The MSE Corrosion model can predict the anodic and cathodic half reactions, passive film formation, and the active-passive transition across a wide range of conditions, including variations in pH, temperature, and electrolyte concentration. The model was calibrated using experimental data from a diverse set of chemical systems, including single acids, acid mixtures, neutral and alkaline solutions, systems containing dissolved oxygen, acid gases etc. Each environment was used to parametrize specific aspects of the corrosion model, ensuring accurate representation under both oxidizing and reducing conditions, while capturing the influence of aggressive and inhibitive species. The mechanistic basis of the model allows it to extrapolate to complex systems and conditions where experimental data may be sparse or unavailable.