Session: RIP: Predictive Modeling and Characterization of Corrosion Processes in Complex Environments (In Honor of Professor Digby Macdonald) (Part I of IV)
Effects of Nitrogen Defects in Chromium Passive Films (RIP2026-00116)
This work investigates the corrosion rate effects of nitrogen defects substituting on the oxygen sublattice of chromium oxide passive films. A theory of defect identity, lattice position, and charge is constructed on the basis of the Hume-Rothery rules for solid solutions. Consequences of the proposed defects are expanded through a solute-vacancy interaction model and then interrogated via XPS, Electrochemical impedance spectroscopy, Mott-Schottky analysis and some DC techniques. Finally, a PDM-based EIS model is proposed and applied to laboratory data on pure Cr films doped with various nitrogen concentrations to test the nitrogen defect theory.
