Study of the passivation mechanism in highly corrosion resistant `stainless steel' alloy coatings formed using the JVD^TM process

In this paper we consider the mechanism by which a `stainless steel' coating produced by the Jet Vapor Deposition Process^TM passivates in the highly corrosive environment of deaerated 4 M HCL. The study involved surface analysis using variable angle x-ray photoelectron spectroscopy (XPS) to determine the nature of the passive film. It was shown that the film contained chromium and molybdenum constituents and was essentially free of iron and nickel. Of the alloy constituents only Molybdenum and Chromium are known to exhibit a passive range in the 4 M HCl. Therefore, we compared the nature of the passive film constituents of these elements with those observed in the alloy. This work provides a guide to the design of the highly corrosion resistant alloys formed by physical vapor deposition.