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arXiv · 2007.05899

Magnetocaloric effect in Ni2(Mn,Cu)Ga0.84Al0.16 Heusler alloys

Alberto A. Mendonca·Luis Ghivelder·Jesus F. Jurado·Angelo M. Gomes
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Abstract

Polycrystalline Heusler compounds Ni2Mn0.75Cu0.25Ga0.84Al0.16 with a martensitic transition between ferromagnetic phases and Ni2Mn0.70Cu0.30Ga0.84Al0.16 with a magnetostructural transformation were investigated by magnetization and thermal measurements, both as a function of temperature and magnetic field. The compound Ni2Mn0.75Cu0.25Ga0.84Al0.16 presents a large magnetocaloric effect among magnetically aligned structures and its causes are explored. In addition, Ni2Mn0.70Cu0.30Ga0.84Al0.16 shows very high, although irreversible, entropy and adiabatic temperature change at room temperature under a magnetic field change 0-1 T. Improved refrigerant capacity is also a highlight of the 30% Cu material when compared to similar Ni2MnGa-based alloys.

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Alberto A. Mendonca, Luis Ghivelder, Jesus F. Jurado, Angelo M. Gomes. 2020-07-12. Magnetocaloric effect in Ni2(Mn,Cu)Ga0.84Al0.16 Heusler alloys. https://doi.org/10.1016/j.jmmm.2021.167965

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