In this study, the effect of Al on the high temperature oxidation of Al-containing refractory high entropy alloys (RHEAs) Ta-Mo-Cr-Ti-xAl (x = 5; 10; 15; 20 at%) was examined. Oxidation experiments were performed in air for 24 h at 1200 °C. The oxidation kinetics of the alloy with 5 at% Al is notably affected by the formation of gaseous MoO₃ and CrO₃, while continuous mass gain was detected for alloys with the higher Al concentrations. The alloys with 15 and 20 at% Al form relatively thin oxide scales and a zone of internal corrosion due to the formation of dense CrTaO₄ scales at the interface oxide/substrate. The alloys with 5 and 10 at% Al exhibit, on the contrary, thick and porous oxide scales because of fast growing Ta₂O₅. The positive influence of Al on the formation of Cr₂O₃ followed by the growth of CrTaO₄ to yield a compact scale is explained by getter and nucleation effects.

在这项研究中，研究了铝对含铝耐火高熵合金 (RHEA) Ta-Mo-Cr-Ti-xAl ( x  = 5; 10; 15; 20 at%) 的高温氧化的影响。氧化实验在空气中于 1200°C 下进行 24 小时。含 5 at% Al 的合金的氧化动力学显着受气态 MoO ₃和 CrO _{3 的影响}，而对于具有较高 Al 浓度的合金，检测到质量持续增加。由于在界面氧化物/基材处形成致密的 CrTaO ₄鳞片，具有 15 和 20 原子％Al 的合金形成相对薄的氧化皮和内部腐蚀区。相反，含有 5 和 10 at% Al 的合金由于快速生长的 Ta 而表现出厚而多孔的氧化皮₂ O ₅。Al 对 Cr ₂ O ₃形成的积极影响，随后是 CrTaO ₄的生长以产生致密的鳞片，这可以通过吸气剂和成核效应来解释。