Determination of the Minimum Surface Enrichment of Molybdenum Required to Inhibit Active Dissolution of an Fe‐Cr‐Ni‐Mo Alloy

Abstract

It is becoming clear that molybdenum inhibits localized corrosion of stainless steels through its effect on the anodic dissolution kinetics, rather than by any mechanism which could be discovered by analyzing the fully developed passive film. Wanklyn has emphasized the importance of MoO/sub 2/ as a compound which is readily formed and is stable at relatively active potentials in mildly acidic solutions. It is also kinetically stable in strongly acidic solutions because of the necessity for reductive dissolution as Mo/sup 3 +/. In the passive state at much higher potentials there is a tendency for depletion of Mo in the passive film.