Design of Structural Alloys with High-Temperature Corrosion Resistance

Abstract

In order for an alloy to possess high-temperature corrosion resistance, the reaction of the alloy with the environment must result in a reaction product that effectively deters all subsequent reaction. It is shown that oxide reaction product barriers, in particular Al2O3, Cr2O3, and SiO2, are the most effective barriers to develop corrosion resistance in alloys. The conditions that must be satisfied in order for such oxides to be formed as continuous barriers on the surfaces of alloys are discussed and described. The stability of these continuous oxide barriers to corrosion induced by ash deposits is considered and methods to improve the adhesion of oxide barriers are examined. Techniques and procedures to be followed in designing alloys for corrosion resistance are proposed.