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arXiv · 0708.0204

Phase diagram and magnetocaloric effect of CoMnGe_{1-x}Sn_{x} alloys

J. B. A. Hamer·R. Daou·S. Özcan·N. D. Mathur·D. J. Fray·K. G. Sandeman
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Abstract

We propose the phase diagram of a new pseudo-ternary compound, CoMnGe_{1-x}Sn_{x}, in the range x less than or equal to 0.1. Our phase diagram is a result of magnetic and calometric measurements. We demonstrate the appearance of a hysteretic magnetostructural phase transition in the range x=0.04 to x=0.055, similar to that observed in CoMnGe under hydrostatic pressure. From magnetisation measurements, we show that the isothermal entropy change associated with the magnetostructural transition can be as high as 4.5 J/(K kg) in a field of 1 Tesla. However, the large thermal hysteresis in this transition (~20 K) will limit its straightforward use in a magnetocaloric device.

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J. B. A. Hamer, R. Daou, S. Özcan, N. D. Mathur, D. J. Fray, K. G. Sandeman. 2007-08-01. Phase diagram and magnetocaloric effect of CoMnGe_{1-x}Sn_{x} alloys. https://doi.org/10.1016/j.jmmm.2008.03.003

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