Reversibility of magnetostructural transition and associated magnetocaloric effect above room temperature in Ni-Co-Mn-In-Gd polycrystal

The magnetocaloric effects (MCE) in polycrystalline Ni45Co5Mn35In14Gd1 alloy were investigated. The magnetic-field-induced phase transformation from martensite to austenite phase is confirmed. Both inverse and an conventional magnetocaloric effects are attained at a magnetic field up to 5 T. Above room temperature (328 K), high inverse magnetic entropy change of 26.8 J/kg K under a 5 T magnetic field is observed around first order magnetostructural transition. The large magnetic entropy change in Ni-Co-Mn-In-Gd alloy is promising for magnetic refrigeration.