Oxidation behavior of Ti-Nb-Mo-Al-Six refractory high entropy alloy at 1000°C

The oxidation behavior of TiNbMo0.5Al0.225Six (x = 0.1, 0.25, 0.4, 0.55) refractory high entropy alloys in air at 1000 degrees C was investigated. These novel alloys have a BCCss / (Nb, Ti)(5)Si-3 eutectic structure in the as-cast state. Oxidation resistance results reveal that the mass gain shifts from a mass loss (Si-0.1) to a parabolic law (Si-0.25, Si-0.4, Si-0.55). An appropriate increase in Si content favors a lower oxidation rate. The beta-(Nb, Ti)(5)Si-3 was studied to have excellent oxidation resistance, while the region where gamma-(Nb, Ti)(5)Si-3 existed is the main site of porosity generation. The suitable Si content promotes the appearance of a Mo-rich layer, thus preventing the oxide evaporation. Data availability: The data that support the findings of this study are available from the corresponding author, specifically Professor Liang Wang of the Harbin Institute of Technology (email: wliang1227@hit.edu.cn) upon reasonable request.