Metallic alloys containing multiple principal alloying elements have created a growing interest in exploring the property limits of metals and understanding the underlying physical mechanisms. Refractory high-entropy alloys have drawn particular attention due to their high melting points and excellent softening resistance, which are the two key requirements for high-temperature applications. Their compositional space is immense even after considering cost and recyclability restrictions, providing abundant design opportunities. However, refractory high-entropy alloys often exhibit apparent brittleness and oxidation susceptibility, which remain important challenges for their processing and application. Here, utilizing natural-mixing characteristics among refractory elements, we designed a Ti₃₈V₁₅Nb₂₃Hf₂₄ refractory high-entropy alloy that exhibits >20% tensile ductility in the as-cast state, and physicochemical stability at high temperatures. Exploring the underlying deformation mechanisms across multiple length scales, we observe that a rare β′-phase plays an intriguing role in the mechanical response of this alloy. These results reveal the effectiveness of natural-mixing tendencies in expediting high-entropy alloy discovery.

包含多种主要合金元素的金属合金引起了人们对探索金属性能极限并了解其基本物理机理的浓厚兴趣。难熔高熵合金由于其高熔点和出色的抗软化性而引起了人们的特别关注，这是高温应用的两个关键要求。即使考虑了成本和可回收性限制，它们的成分空间仍然很大，从而提供了丰富的设计机会。然而，难熔的高熵合金通常表现出明显的脆性和氧化敏感性，这对于它们的加工和应用仍然是重要的挑战。在这里，利用耐火元素之间的自然混合特性，我们设计了Ti ₃₈ V ₁₅Nb ₂₃ Hf ₂₄难熔高熵合金，在铸态下具有> 20％的拉伸延展性，并在高温下具有物理化学稳定性。探索跨多个长度尺度的潜在变形机制，我们观察到稀有的β'相在这种合金的机械响应中起着有趣的作用。这些结果揭示了自然混合趋势在加速高熵合金发现中的有效性。