High temperature oxidation of a CrN coating deposited on a steel substrate by ion plating

A Cr(0.644)N(0.356) coating was deposited on a steel substrate by are-ion plating. The oxidation characteristics of the deposited coating, which was composed of CrN and Cr(2)N phases, were studied at temperatures ranging from 700 to 950 degreesC in air. The coating displayed good oxidation resistance up to 950 degreesC. The oxidation product was primarily Cr(2)O(3), which contained some dissolved nitrogen and the substrate element of iron. The unreacted coating beneath the oxide scale had some dissolved oxygen and iron. The oxidation of the Cr(0.644)N(0.356) coating occurred via complex routes such as predominant outward diffusion of chromium, nitrogen and iron and inward transport of oxygen. (C) 2001 Elsevier Science B.V. All rights reserved.