Abstract Refractory high-entropy alloys (RHEAs) usually have a high strength at elevate temperatures. However, their oxidation resistance is inferior for practical applications. Here we proposed a eutectic design of compositionally complex eutectic alloy (CCEA) by adding 10 at. % Ta to the Al2Co28Cr20Fe25Ni25, the resulting alloy shows a good combination of mechanical properties and oxidation resistance, e.g. a yield strength of 764 MPa and an oxidation resistance rate of 0.0031 mg cm−2h−1 at 800 °C, which outperforms those of RHEAs. The excellent oxidation resistance is attributable to the formation of protective Cr2O3 and CrTaO4 layer at the surface, which prevents the matrix from further contact with O2.

中文翻译：

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揭示非等摩尔Al1Co25Cr18Fe23Ni23Ta10成分复合共晶合金优异的高温抗氧化性

摘要 难熔高熵合金（RHEAs）在高温下通常具有较高的强度。然而，它们的抗氧化性在实际应用中较差。在这里，我们通过添加 10 at 提出了一种成分复杂的共晶合金 (CCEA) 的共晶设计。% Ta 与 Al2Co28Cr20Fe25Ni25 相比，所得合金表现出良好的机械性能和抗氧化性，例如在 800 °C 下屈服强度为 764 MPa，抗氧化率为 0.0031 mg cm-2h-1，优于 RHEAs . 优异的抗氧化性归因于在表面形成保护性 Cr2O3 和 CrTaO4 层，防止基体进一步与 O2 接触。