In present work, we investigate the elemental partition behaviors in L1 ordered intermetallics and its influence on mechanical properties in a Ni-Co-Cr-Al-Ta medium-entropy alloy (MEA) system through a combination of density functional theory (DFT) calculations and experimental investigation. Our finding reveal that Ta has a strong tendency to occupy Al sublattice, while Co prefers Ni sublattice, Cr, on the other hand, randomly occupy Al and Ni sublattices, resulting in the formation of the multicomponent (Ni, Co, Cr)(Al, Ta, Cr) L1 intermetallics. Among the constituent elements, Ta is identified as an efficient element for enhancing hardening of the alloy. Furthermore, we demonstrate that improving Ta/Al ratio leads to a significant increase in anti-phase boundary (APB) energy, resulting in superior precipitation hardening effects and excellent mechanical properties. Our founding provide valuable insights for further the rationally design and rapid development of high performance L1-strengthened alloys.

中文翻译：

---

通过调节反相边界能优化 L12 强化中熵合金中的沉淀硬化

在目前的工作中，我们通过结合密度泛函理论（DFT）计算研究了Ni-Co-Cr-Al-Ta中熵合金（MEA）体系中L1有序金属间化合物的元素分配行为及其对机械性能的影响和实验研究。我们的研究结果表明，Ta 强烈倾向于占据 Al 亚晶格，而 Co 更倾向于占据 Ni 亚晶格，而 Cr 则随机占据 Al 和 Ni 亚晶格，从而形成多组分 (Ni, Co, Cr)(Al ,Ta,Cr)L1金属间化合物。在组成元素中，Ta被认为是增强合金硬化的有效元素。此外，我们还证明，提高 Ta/Al 比例会导致反相界 (APB) 能量显着增加，从而产生优异的沉淀硬化效果和优异的机械性能。我们的成立为进一步合理设计和快速开发高性能 L1 强化合金提供了宝贵的见解。