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arXiv · 1003.6116

Giant magneto-caloric effect near room temperature in Ni-Mn-Sn-Ga alloys

S. Chatterjee·S. Giri·S. Majumdar·S. K. De
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Abstract

We report the observation of giant magneto-caloric effect (MCE) in ferromagnetic shape memory alloys (FSMAs) of nominal compositions Ni$_2$Mn$_{1.36}$Sn$_{0.64-x}$Ga$_{x}$ ($x$ =0.24, 0.28 and 0.32). Irrespective of the Ga doping, all the samples undergo long range ferromagnetic ordering below around 330 K. However, the martensitic transition temperature ($T_{MS}$) of the samples varies strongly with Ga concentration. Clear signature of field induced transition around $T_{MS}$ is visible for all the samples. The observed MCE ($\Delta S$ = 13.6 J/kg K for field changing from 0 to 50 kOe) is found to be highest for $x$ = 0.28 with peak near 249 K, while $x$ = 0.32 shows $\Delta S$ = 12.8 J/kg K at 274 K. This series of Ga-doped alloys are found to be interesting materials with high value of $\Delta S$ over a varied range of temperature

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S. Chatterjee, S. Giri, S. Majumdar, S. K. De. 2010-03-31. Giant magneto-caloric effect near room temperature in Ni-Mn-Sn-Ga alloys. https://doi.org/10.1016/j.jallcom.2010.05.026

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