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arXiv · 2007.10428

The large magnetocaloric effect and refrigerant capacity in nanocrystalline/ amorphous Gd$_3$Ni/Gd$_{65}$Ni$_{35}$ composite microwires

Y. F. Wang·Y. Y. Yu·H. Belliveau·N. T. M. Duc·H. X. Shen·J. F. Sun·J. S. Liu·F. X. Qin·S. C. Yu·H. Srikanth·M. H. Phan
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Abstract

We report on a novel class of nanocrystalline/amorphous Gd$_3$Ni/Gd$_{65}$Ni$_{35}$ composite microwires, which was created directly by melt-extraction through controlled solidification. X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed the formation of a biphase nanocrystalline/amorphous structure in these wires. Magnetic and magnetocaloric experiments indicate the large magnetic entropy change (-$\Delta$SM ~9.64 J/kg K) and the large refrigerant capacity (RC ~742.1 J/kg) around the Curie temperature of ~120 K for a field change of 5 T. These values are ~1.5 times larger relative to its bulk counterpart, and are superior to other candidate materials being considered for active magnetic refrigeration in the liquid nitrogen temperature range.

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Y. F. Wang, Y. Y. Yu, H. Belliveau, N. T. M. Duc, H. X. Shen, J. F. Sun, J. S. Liu, F. X. Qin, S. C. Yu, H. Srikanth, M. H. Phan. 2020-07-20. The large magnetocaloric effect and refrigerant capacity in nanocrystalline/ amorphous Gd$_3$Ni/Gd$_{65}$Ni$_{35}$ composite microwires. https://arxiv.org/abs/2007.10428

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