Silva L E L, Patiño J C, Gomes A M
Instituto de Física, Departamento de Física dos Sólidos, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
J Phys Condens Matter. 2021 May 10;33(23). doi: 10.1088/1361-648X/abe89f.
Full Heusler alloys present martensitic transition and shape memory effect related phenomena and several technological applications can be envisaged. One promising area is the magnetocaloric effect (MCE) as the magnetic and structural transitions combine to produce a large isothermal entropy and adiabatic temperature change useful for heating and cooling applications. In this work, we study a Ni-(Mn, Cu)-(Ga, Al) Heusler alloy family which has a giant MCE when the chemical composition is fine-tuned to bring the temperature of the second-order magnetic transition close the first-order structural one. Our results show that, for a certain range of copper concentration, the samples show interesting physical properties captured by calorimetric, microscopy imaging, and magnetization measurements, leading to a high MCE with minimized hysteresis.
全赫斯勒合金呈现出马氏体转变和与形状记忆效应相关的现象，并且可以设想多种技术应用。一个有前景的领域是磁热效应（MCE），因为磁转变和结构转变相结合会产生较大的等温熵变和绝热温度变化，这对于加热和冷却应用很有用。在这项工作中，我们研究了一种Ni-(Mn, Cu)-(Ga, Al)赫斯勒合金系，当化学成分经过微调使二级磁转变温度接近一级结构转变温度时，该合金系具有巨大的磁热效应。我们的结果表明，在一定的铜浓度范围内，样品表现出通过量热法、显微镜成像和磁化测量所捕捉到的有趣物理性质，从而产生具有最小磁滞的高磁热效应。
