Colossal magnetocaloric effect in Ni-Co-Mn-In alloys induced by electron irradiation

Magnetocaloric materials have shown huge potential for magnetic refrigeration but fail meeting the application standard because of the low magnetic entropy change Delta S-M. In this work, high-energy electron irradiation is used to enlarge the magnetization difference Delta M in the inverse martensitic transition for Ni-Co-Mn-In alloys, which is mainly attributed to the variations of the short-range atomic arrangement and electronic structure. As a result, the Delta S-M can reach up to 62.17 J/(kgK) only with a small magnetic field of 3 T. Even compared with the Delta S-M of other works measured under 5 T magnetic field, this value is much superior and can be further improved up to 136.16 J/(kgK) with increasing the magnetic field to 7 T. Such high Delta S-M could improve the attractiveness of the material for the actual application. (C) 2020 Elsevier Ltd. All rights reserved.