Alumina-Forming Austenitic Alloys Resist High-Temperature Corrosion

摘要

A new class of high-temperature alumina-forming austenitic (AFA) stainless steel (SS) alloys that deliver both superior corrosion and creep resistance for many industrial environments—without sacrificing the typical lower cost, formability, and weldability of conventional high-temperature SS—has been developed by researchers with the Oak Ridge National Laboratory (ORNL) (Oak Ridge, Tennessee). The outstanding corrosion resistance of these alloys is due to their unique composition, which allows the formation of a protective aluminum oxide (Al_2O_3 [alumina]) scale layer on the metal's surface that provides significant oxidation resistance. This protective layer permits the use of these alloys at higher temperatures and for longer time periods than SS alloys that form a protective chromium oxide (Cr_2O_3 [chromia]) surface layer.