A comparative Study on the Oxidation Behaviours of a TNM Alloy in Argon and Oxygen Atmospheres at 650 °C

Abstract This study investigated the oxidation behaviours of a TiAl (TNM) alloy oxidized at 650 °C in argon and oxygen. The oxidation mass gains were similar in both atmospheres up to 200 h of oxidation. Between 200 and 500 h, the mass gains increased by 20% in the O2 atmosphere. This study examined the triplex oxide scales of outer (Ti–Al)O layer-by-layer and Mo/Nb-rich TiAl oxides on the TNM alloy after oxidation in Ar and O2. The scale structures formed in Ar and O2 were similar but differed from those formed in air, and the respective TNM samples’ oxidation behaviours were different.