The present study investigated the influences of Dy-addition on the microstructural characterization, functional behaviour and deformation mechanisms in high-temperature Ni₅₄Mn₂₅Ga₂₁ alloys. The results indicated that adequate Dy-addition contributed to a desirable trade-off among compressive strength, ductility and functional performance. Ni₅₄Mn₂₅Ga_20.9Dy_0.1 alloy showed the highest shape memory recoverable strain due to the improvement of mechanical properties and formation of small Dy-rich precipitates. Meanwhile, an obvious pseudoelasticity was observed over a wide temperature range with a maximum recoverable strain of 3.74% at 320°C in this alloy. All the Dy-containing alloys exhibited low thermal hysteresis. However, it was revealed that an abnormal relationship between thermal hysteresis and middle eigenvalue ${\lambda }_2$ existed for the investigated alloys with a lattice transition from cubic to tetragonal.

本研究调查了 Dy 添加对高温 Ni ₅₄ Mn ₂₅ Ga ₂₁合金的显微组织表征、功能行为和变形机制的影响。结果表明，足够的 Dy 添加有助于在压缩强度、延展性和功能性能之间取得理想的平衡。Ni ₅₄ Mn ₂₅ Ga _20.9 Dy _0.1由于改善了机械性能并形成了少量富含Dy的析出物，该合金显示出最高的形状记忆可恢复应变。同时，在较宽的温度范围内观察到明显的伪弹性，该合金在 320°C 时的最大可恢复应变为 3.74%。所有含 Dy 的合金都表现出低的热滞后。然而，揭示了热滞后和中间特征值之间的异常关系${\lambda }_2$ 对于所研究的合金，其晶格从立方体转变为四方体。