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arXiv · 1303.7282

Giant magnetocaloric effect in isostructural MnNiGe-CoNiGe system by establishing a Curie-temperature window

E. K. Liu·H. G. Zhang·G. Z. Xu·X. M. Zhang·R. S. Ma·W. H. Wang·J. L. Chen·H. W. Zhang·G. H. Wu·L. Feng·X. X. Zhang
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Abstract

An effective scheme of isostructural alloying was applied to establish a Curie-temperature window in isostructural MnNiGe-CoNiGe system. With the simultaneous accomplishment of decreasing structural-transition temperature and converting antiferromagnetic martensite to ferromagnetic state, a 200 K Curie-temperature window was established between Curie temperatures of austenite and martensite phases. In the window, a first-order magnetostructural transition between paramagnetic austenite and ferromagnetic martensite occurs with a sharp jump in magnetization, showing a magnetic entropy change as large as -40 J kg-1 K-1 in a 50 kOe field change. This giant magnetocaloric effect enables Mn1-xCoxNiGe to become a potential magnetic refrigerant.

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E. K. Liu, H. G. Zhang, G. Z. Xu, X. M. Zhang, R. S. Ma, W. H. Wang, J. L. Chen, H. W. Zhang, G. H. Wu, L. Feng, X. X. Zhang. 2013-03-29. Giant magnetocaloric effect in isostructural MnNiGe-CoNiGe system by establishing a Curie-temperature window. https://doi.org/10.1063/1.4798318

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