THE ROLE OF PASSIVE FILM GROWTH KINETICS AND PROPERTIES IN STRESS CORROSION AND CREVICE CORROSION SUSCEPTIBILITY

摘要

A study of the effect of alloying chromium and molybdenum in ferritic stainless steels has been made using techniques to study repassivation kinetics (tribo-ellipsometry) and depassivation kinetics (a recently developed ellipsometry technique for studying optical changes occurring within a crevice). Results indicate that chromium additions affect both repassivation and depassivation processes while molybdenum appears to affect only the repassivation processes. A discussion is given of a generalized mechanism for localized corrosion which postulates that susceptibility to attack is determined by the competititon between depassivation and repas¬sivation processes.