Effects of Minor Alloy Additions and Oxidation Temperature on Protective Alumina Scale Formation in Creep-Resistant Austenitic Stainless Steels

Abstract

Alumina scale formation in newly developed creep-resistant austenitic stainless steels was found to be sensitive to Al, Nb, Ti, and V content and oxidation temperature. Ti and V synergistically degraded the ability to form a protective alumina scale, whereas Nb was beneficial for alumina scale formation. The ability to form external alumina scales was lost in the lower Al and Nb containing alloys between 800 and 900�aC. Compositions with the potential to form alumina at 900�aC (and possibly higher) were identified.