Corrosion resistance of chromium carbide coatings in oxygen-sulfur environments

Abstract

Oxidation of metallic materials at elevated temperatures in bioxidant environments is a potential problem in many systems in the chemical, petroleum and power-generating industries. The use of appropriate corrosion-resistant coatings on metallic components offers an avenue to minimize the material degradation and to extend the life of the component. This paper discusses results obtained when Type 310 stainless steel (SS) and chromium-carbide- and chromium-coated Type 310 SS were exposed to oxidizing and sulfidizing gas mixtures. The coatings were developed by an electro-spark deposition process in which short-duration, high-current electrical pulses were used to deposit the electrode material on the metallic substrate. Thermogravimetric test data, observations on the morphology of coating layers, and hardness depth profiles for coated and uncoated specimens after exposure to several gas mixtures at temperatures of 875 and 650 °C are presented.