Strong correlation between high temperature oxidation resistance and nitrogen mass gain during near alpha titanium alloys exposure in air

Abstract

Nitrogen is known to play a role in the oxidation of titanium and titanium alloys in air. This paper shows the strong correlation between the high temperature oxidation kinetics of eight near-alpha titanium alloys, in the class of Ti6242S, exposed for 3000 h in air at 650 °C. Nuclear reaction analysis (NRA) was used to quantify and locate the nitrogen inside the material. An excellent linear correlation between the total mass gain measured by gravimetry and the nitrogen mass gain measured by NRA is revealed: less the alloys oxidize, more the nitrogen in involved in the oxidation process.