High-entropy alloys (HEAs) with a single-phased face-centered-cubic structure possess excellent plasticity but generally low strength. Precipitation strengthening is one of the most promising methods to improve the strength of alloys. However, plagued by a nerve-wracking fact that strength-ductility trade-off frequently limits the improvement of alloy properties. To overcome this problem, a new Ni₃₅(CoFe)₅₅V₅Nb₅ HEA with an excellent strength and ductility synergy was developed by introducing a novel bifunctional L1₂-Ni₃Nb nano-precipitate. This HEA exhibits a high yield strength of 855 MPa, ultimate tensile strength of 1,302 MPa and marvelous elongation of ∼ 50%. First-principles calculations show that the (Ni₂₄Co₁₈Fe₆)₃(Nb₁₀V₄Fe₂) nano-precipitate with a L1₂ structure possesses lower formation energy than that with D0₂₂ structure. The novel nano-precipitates provide two-fold functions. On the one hand, L1₂-(Ni₂₄Co₁₈Fe₆)₃(Nb₁₀V₄Fe₂) nano-precipitates have a high anti-phase boundary energy, contributing to a significant increment in the yield strength through precipitation strengthening. More importantly, the precipitation of the precipitates lowers the stacking fault energy (SFE) of the alloy matrix, contributing to the excellent work-hardening ability and large plasticity through activating the continuous formation of SF networks and Lomer-Cottrell locks during deformation. The strategy to introduce the novel bifunctional nano-precipitates paves a new way to enhance the strength-ductility synergy of alloys.

具有单相面心立方结构的高熵合金（HEA）具有优异的塑性，但强度普遍较低。沉淀强化是提高合金强度的最有前景的方法之一。然而，受到一个令人伤脑筋的事实的困扰，即强度-延展性的权衡经常限制合金性能的改善。为了克服这个问题，通过引入新型双功能 L1 ₂ -Ni ₃开发了具有优异强度和延展性协同作用的新型 Ni ₃₅ (CoFe) ₅₅ V ₅ Nb _{5 HEA}Nb 纳米沉淀。该 HEA 具有 855 MPa 的高屈服强度、1,302 MPa 的极限抗拉强度和 50% 的惊人伸长率。第一性原理计算表明， L1 _{2结构的(Ni 24} Co ₁₈ Fe ₆ ) ₃ (Nb ₁₀ V ₄ Fe ₂ )纳米析出物的形成能低于D0 ₂₂结构。新型纳米沉淀物提供了双重功能。一方面，L1 ₂ -(Ni ₂₄ Co ₁₈ Fe ₆ ) ₃ (Nb ₁₀ V ₄ Fe₂ ) 纳米析出物具有高反相边界能，通过析出强化有助于显着提高屈服强度。更重要的是，析出物的析出降低了合金基体的层错能（SFE），通过在变形过程中激活SF网络和Lomer-Cottrell锁的连续形成，有助于获得优异的加工硬化能力和较大的塑性。引入新型双功能纳米沉淀物的策略为增强合金的强度-塑性协同作用铺平了新的道路。