The comparison of direct and indirect methods for determining the magnetocaloric parameters in the Heusler alloy Ni50Mn34.8In14.2B

The magnetocaloric properties of the Ni50Mn34.8In14.2B Heusler alloy have been studied by direct measurements of the adiabatic temperature change (Delta T-AD(T,H)) and indirectly by magnetization (M(T,H)), differential scanning calorimetry, and specific heat (C(T,H)) measurements. The presence of a first-order ferromagnetic-paramagnetic transition has been detected for Ni50Mn34.8In14.2B at 320 K. The magnetocaloric parameters, i.e., the magnetic entropy change (Delta S-M = (2.9-3.2) J/kgK) and the adiabatic temperature change (Delta T-AD = (1.3-1.52) K), have been evaluated for Delta H = 1.8 T from C-P(T,H) and M(T,H) data and from direct Delta T-AD(T,H) measurements. The extracted magnetocaloric parameters are comparable to those of Gd. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4714539]