Abstract The refractory high entropy alloy (RHEA) has shown great potentials for high temperature applications beyond modern Ni-based superalloy. However, its oxidation behaviours are rarely reported and understood. In this work, the oxidation behaviours of a novel RHEA “NV1”, Cr-17.6Al-20.3Mo-15.2Nb-2.9Si-13.4Ta-5.4Ti (in at%), were examined at 1200, 1300, and 1400 °C up to 100 h. At 1200 °C, the oxidation kinetics curve yielded toward parabolic behaviour owing to the formation of a rutile-type complex oxide layer with Al2O3 and Cr2O3 dispersions; breakaway oxidation contributed by Cr2O3 evaporation occurred at 1300 °C; a single power-law behaviour governed the oxidation kinetics curve at 1400 °C, and mullite was identified within the oxide layer. This work provides guidelines for understanding the oxidation mechanisms and improving oxidation resistance of RHEA at elevated temperature.

中文翻译：

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一种新型难熔高熵合金在高温下的氧化行为

摘要 耐火高熵合金（RHEA）在现代镍基高温合金之外的高温应用中显示出巨大的潜力。然而，它的氧化行为很少被报道和理解。在这项工作中，研究了新型 RHEA“NV1”、Cr-17.6Al-20.3Mo-15.2Nb-2.9Si-13.4Ta-5.4Ti（以原子百分比计）在 1200、1300 和 1400° 下的氧化行为C 长达 100 小时。在 1200 °C 时，由于形成了具有 Al2O3 和 Cr2O3 分散体的金红石型复合氧化物层，氧化动力学曲线趋向抛物线行为；Cr2O3 蒸发造成的分离氧化发生在 1300 °C；在 1400 °C 时，单一的幂律行为控制着氧化动力学曲线，并且在氧化层内发现了莫来石。