High-temperature steam oxidation behavior of alumina-forming duplex FeNiCrAl and ferritic FeCrAl alloys at 800 degrees C to 1050 degrees C

Abstract

Two alumina-forming Fe-based alloys, duplex FeNiCrAl (alumina-forming duplex stainless steel, ADSS) and ferritic FeCrAl (APM) alloys, were oxidized in steam at 800 degrees C to 1050 degrees C for up to 72 h. Formation of spinel oxides on ADSS resulted in larger weight gain than APM, while the highest weight gain was observed at 900 degrees C. Outer gamma- and/or 0-alumina and inner alpha-alumina were formed on APM, whereas dispersed spinel oxides as well as gamma- and alpha-alumina on ADSS. Similar alumina formation kinetics was observed for both alloys, while transient alumina formation resulted in faster kinetics at 900 degrees C.