Publication | Closed Access
A Point Defect Model for Anodic Passive Films: I . Film Growth Kinetics
870
Citations
0
References
1981
Year
Point DefectsEngineeringThin Film Process TechnologyFilm Growth KineticsDefect ToleranceCorrosionPassive FilmThin Film ProcessingMaterials ScienceMaterials EngineeringElectromigration TechniquePhysicsField StrengthAnodic Passive FilmsDefect FormationPoint Defect ModelInterface PropertySurface ScienceApplied PhysicsInterfacial PhenomenaThin FilmsChemical Vapor Deposition
The authors propose a point‑defect model in an electrostatic field to explain passive film growth on metal surfaces. The model describes film growth through the migration of point defects driven by the electrostatic field. It predicts a logarithmic growth law that fits experimental iron passive film data, with a field‑strength‑dependent potential difference (α = 0.743, independent of anion) and a pH‑dependent β that varies with anion identity.
A model based on the movement of point defects in an electrostatic field is proposed to interpret the growth behavior of a passive film on a metal surface. This model results in a logarithmic growth law. The theoretical equations derived from the model readily account for experimental data for the growth of a passive film on iron. It is found that the field strength of the film is . The dependence of film/solution interface potential difference on the applied potential (α) was found to be 0.743, and is independent of the identity of the anion in solution. However, the dependence of the potential difference across the film/solution interface on the solutionpH (β) is strongly dependent on the identity of the solution anion.