In this work, a novel non-equiamotic Ni₄₆Cr₂₃Co₂₃Al₄Ti₄ medium-entropy alloy (MEA) strengthened by nanoscale coherent γ′ particles with L1₂ superlattice was successfully synthesized, then its microstructure, mechanical properties, strengthening and deformation mechanism were systemically investigated. Our experimental results demonstrated that this precipitation strengthened MEA exhibited outstanding strength-ductility synergy, combination a high yield strength of ∼920 MPa, an ultimate tensile strength of ∼1320 MPa and an excellent ductility of ∼36%. The nanosized γ′ particles bought out effective precipitation strengthening in this non-equiamotic MEA, contributing a majority yield strength enhancement of ∼600 MPa. For this γ′-strengthened MEA, the dominant deformation model was the stacking-faults controlled mode rather than the mechanical twin dominated mode in single-phase face-centered-cubic structure Ni₅₀Cr₂₅Co₂₅ MEA. Our work provides a further understanding of precipitate strengthening in non-equiamotic high-entropy alloys (HEAs)/MEAs.

在这项工作中，一种新型的非等渗Ni ₄₆ Cr ₂₃ Co ₂₃ Al ₄ Ti ₄中熵合金（MEA）被纳米相干γ'粒子与L1 ₂增强成功地合成了超晶格，然后系统地研究了其超微结构，力学性能，增强和变形机理。我们的实验结果表明，这种沉淀增强型MEA具有出色的强度-延展性协同作用，具有约920 MPa的高屈服强度，约1320 MPa的极限抗拉强度和约36％的出色延展性。纳米级的γ'颗粒在这种非等离子MEA中获得了有效的沉淀增强作用，从而使屈服强度提高了约600 MPa。对于这种γ'增强MEA，主要变形模型是单相面心立方结构Ni ₅₀ Cr ₂₅ Co中的堆垛层错控制模式，而不是机械孪生控制模式。₂₅ MEA。我们的工作提供了对非等离子高熵合金（HEA）/ MEA中沉淀物强化的进一步理解。