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arXiv · 2002.05303

High-Field Magnetization and Magnetic Phase Diagram of Metamagnetic Shape Memory Alloys Ni50-xCoxMn31.5Ga18.5 (x = 9 and 9.7)

Takumi Kihara·Xiao Xu·Atsushi Miyake·Yuto Kinoshita Masashi Tokunaga·Yoshiya Adachi·Takeshi Kanomata
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Abstract

Magnetic phase diagrams of the metamagnetic shape memory alloys Ni50-xCoxMn31.5Ga18.5 (x = 9 and 9.7) were produced from high-field magnetization measurements up to 56 T. For both compounds, magnetic field induced martensitic transformations are observed at various temperatures below 300 K. Hysteresis of the field-induced transformation shows unconventional temperature dependence: it decreases with decreasing temperature after showing a peak. Magnetic susceptibility measurement, microscopy, and X-ray diffraction data suggest a model incorporating the magnetic anisotropy and Zeeman energy in two variants, which qualitatively explains the thermal and the magnetic field history dependence of the hysteresis in these alloys.

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Takumi Kihara, Xiao Xu, Atsushi Miyake, Yuto Kinoshita Masashi Tokunaga, Yoshiya Adachi, Takeshi Kanomata. 2020-02-13. High-Field Magnetization and Magnetic Phase Diagram of Metamagnetic Shape Memory Alloys Ni50-xCoxMn31.5Ga18.5 (x = 9 and 9.7). https://doi.org/10.1016/j.scriptamat.2020.02.009

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