Surface Enrichment of Nitrogen during Passivation of a Highly Resistant Stainless Steel

Abstract

Nitrogen, probably in an uncharged form, is enriched on the metal side of the metal film interface after passivation of the number 30 alloy. Molybdenum is probably present in the oxide film, but is depleted compared with the bulk alloy and shows no obvious association with nitrogen. The improvement of passivity by alloying with nitrogen probably results from segregation of nitrogen to the metal surface during preferential dissolution of metal atoms, rather than from its incorporation into an oxide film.