Compositionally complex alloys (CCAs), also termed as high entropy alloys (HEAs) or multi-principal element alloys (MPEAs), are being considered as a potential solution for many energy-related applications comprising extreme environments and temperatures. Herein, a review of the pertinent literature is performed in conjunction with original works characterising the oxidation behaviour of two diverse Al-containing alloys; namely a lightweight (5.06 g/cm³) single-phase AlTiVCr CCA and a multiple-phase Al_0.9FeCrCoNi CCA (6.9 g/cm³). The thermogravimetric results obtained during oxidation of the alloys at 700 and 900 °C revealed that both alloys tended to obey the desired parabolic rate law. Post-exposure analysis by means of electron microscopy indicated that while the oxide scale formed on the AlTiVCr is adherent to the substrate, the scale developed on the Al_0.9FeCrCoNi displays a notable spalling propensity. This study highlights the need for tailoring the protective properties of the oxide scale formed on the surface of the CCAs.

成分复杂的合金（CCAs），也称为高熵合金（HEA）或多原则元素合金（MPEA），被认为是包括极端环境和温度在内的许多能源相关应用的潜在解决方案。在此，结合表征两种不同含铝合金的氧化行为的原始工作对相关文献进行回顾。即轻量级（5.06 g / cm ³）单相AlTiVCr CCA和多相Al _0.9 FeCrCoNi CCA（6.9 g / cm ³）。合金在700和900°C氧化过程中获得的热重分析结果表明，两种合金都倾向于遵守所需的抛物线速率定律。通过电子显微镜进行的曝光后分析表明，虽然在AlTiVCr上形成的氧化皮附着在基材上，但在Al _0.9 FeCrCoNi上形成的氧化皮显示出明显的剥落倾向。这项研究强调需要调整在CCA表面上形成的氧化皮的保护性能。