Magnetocaloric Effect in Ni-Cu-Mn-Gd-Ga Alloy. XI Symposium of Magnetic Measurements
K. Sielicki, R. Wróblewski and M. Leonowicz
Faculty of Material Science and Engineering, Warsaw University of Technology, Wołoska 141, 02-507 Warsaw, Poland
Received: February 2, 2015
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The magnetocaloric effect of the Ni-Cu-Mn-Gd-Ga polycrystalline alloy was investigated. The nominal composition of the alloy was Ni50Cu6.25Mn16.75Ga25Gd2 at.%. The X-ray diffraction studies revealed presence of two phases at room temperature. This was confirmed by magnetic measurements conducted in low field of 4 kA/m (50 Oe), which showed two Curie transition temperatures, one in vicinity and the other one well above the room temperature. The analysis of isothermal magnetic curves allowed the calculation of magnetic entropy change (ΔSM). Although the peak value of |ΔSM| is relatively low, ≈1.1 J/(kg K), it is very broad. The adiabatic temperature change (ΔT) measured near room temperature is ≈0.49 K. Such result is irrespective of the magnetizing-demagnetizing cycle frequency which varied from 2/min to 10/min.

DOI: 10.12693/APhysPolA.128.120
PACS numbers: 75.30.Sg