In the present study, the Ni28Cu22Ti25Zr10Hf15 high entropy shape memory alloy was designed to optimize its mechanical and functional properties on the basis of the unexpectable performances of high entropy alloys. It was revealed that the microstructure of the present Ni28Cu22Ti25Zr10Hf15 high entropy shape memory alloy was characterized by the dendrite-interdendrite structure modified with second phases. For comparison, the present Ni28Cu22Ti25Zr10Hf15 high entropy shape memory alloy showed the excellent combination of higher fracture strength of ∼2000MPa, superior superelasticity behavior with the fully recoverable strain of 8 %, larger elastocaloric effect with the maximum adiabatic temperature change (ΔTad) of 12.9 K as well as the excellent cycling stability. The higher fracture strength and the perfect superelasticity can be attributed to the severe lattice distortion and solid solution strengthening effects of multiple principal elements, whereas the larger elastocaloric effect as well as the superior cycling stability were stemmed from the lower dissipated energy owing to the good lattice compatibility between the martensite phase and austenite phase.

中文翻译：

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在 Ni-Ti 基高熵形状记忆合金中实现更高的强度、更大的可恢复应变和弹性热量效应


在本研究中，Ni28Cu22Ti25Zr10Hf15 高熵形状记忆合金在高熵合金的意外性能基础上进行了优化其力学和功能性能。结果表明，目前的 Ni28Cu22Ti25Zr10Hf15 高熵形状记忆合金的微观组织表现为经第二相改性的枝晶-枝晶结构。相比之下，目前的 Ni28Cu22Ti25Zr10Hf15 高熵形状记忆合金表现出 ∼2000MPa 的更高断裂强度、卓越的超弹性行为和 8 % 的完全可恢复应变、更大的弹热效应（最大绝热温度变化 （ΔTad）为 12.9 K）以及出色的循环稳定性。较高的断裂强度和完美的超弹性可归因于多种主元素的严重晶格变形和固溶强化作用，而较大的弹热效应和优异的循环稳定性源于马氏体相和奥氏体相之间良好的晶格相容性带来的较低耗散能量。