Giant elastocaloric effect with wide temperature window in an Al-doped nanocrystalline Ti-Ni-Cu shape memory alloy
Giant elastocaloric effect with wide temperature window in an Al-doped nanocrystalline Ti-Ni-Cu shape memory alloy
复制标题
Al掺杂纳米晶Ti-Ni-Cu形状记忆合金中具有宽温度窗口的巨弹热效应
DOI：
10.1016/j.actamat.2019.07.033
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发表时间：
2019
期刊：
影响因子：
9.4
通讯作者：
Takashi Fukuda
中科院分区：
文献类型：
--
作者：
Hong Chen;Fei Xiao;Xiao Liang;Zhenxing Li;Zhu Li;Xuejun Jin;Takashi Fukuda
Ti-Ni基形状记忆合金是一种很有前途的固体制冷弹热材料。本文研究了连续B2-B19-B19′相变纳米晶Ti-44 Ni-5Cu-1Al（at%）合金的弹热效应。从600 MPa开始，应力消除的最大绝热温降为ΔTadi <$25 K，温度分布较小，为<$0.5 K。Δ Tadi值与根据应变-温度关系计算的结果一致。有效工作温度窗口为1055 K，导致RC = 4.2 kJ/kg的高制冷量。当考虑奥托循环时，材料性能系数达到COP = 9.6。转换矩阵的中间特征值λ2 = 0.99，表明母相和马氏体相之间具有很高的晶格相容性。这些性质与该合金B2-B19-B19'马氏体连续相变的扩散性质有关。
Ti–Ni based shape memory alloys are promising elastocaloric materials for solid-state refrigeration. In this paper, we made a comprehensive study on elastocaloric effect of a nanocrystalline Ti–44Ni–5Cu–1Al (at%) alloy exhibiting successive B2–B19–B19′ transformation. The maximum adiabatic temperature decrease by stress removal from 600 MPa is ΔTadi∼25 K with a small temperature distribution of ∼0.5 K. The value of ΔTadiis consistent with that calculated from strain-temperature relation. The effective working temperature window is ∼55 K, resulting in a high refrigeration capacity of RC = 4.2 kJ/kg. Material coefficient of performance reaches COP ∼9.6 when an Otto cycle is considered. The middle eigenvalue of the transformation matrix is λ2∼ 0.99, implying high lattice compatibility between the parent and martensite phases. These properties are related to the diffuse nature of successive B2–B19–B19’ martensitic transformation of this alloy.