Abstract

The magnetic properties and reversibility of the magnetocaloric effect of Ni50Mn35In15 have been studied in the vicinity of the phase transition using magnetization and direct adiabatic temperature change (Delta T-ad) measurements in magnetic fields up to 14 T. The magnetostructural phase transitions (MSTs) between a martensitic phase (MP) with low magnetization (paramagnetic or antiferromagnetic) and a nearly ferromagnetic austenitic phase were detected from thermomagnetic curves, M(T,H), at the applied magnetic fields up to 5 T. The MST temperature was found to be nearly independent of magnetic field for H 5 T, and shifted to lower temperature with the further increase of magnetic field to 14 T. A large and nearly reversible inverse magnetocaloric effect (MCE) with Delta T-ad similar to -11 kappa for a magnetic field change of Delta H = 14 T was observed in the vicinity of the MST. The irreversibility of Delta T-ad was found to be 1 K. A direct Delta T-ad of +7 K for Delta H = 14 T was detected at the second order ferromagnetic-paramagnetic phase transition. The obtained results have been discussed in terms of the suppression of antiferromagnetic correlations with the application of a strong magnetic field, and a reversibility of the initial magnetic state of the MP with applied magnetic field when the MST coincides with T-C. (C) 2016 Elsevier B.V. All rights reserved.