2026-04-17T13:58:45Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1915262025-12-04T20:43:33Zcom_2072_1057col_2072_478822col_2072_478917

00925njm 22002777a 4500 dc Gottschall, Tino author Stern Taulats, Enric author Mañosa, Lluís author Planes Vila, Antoni author Skokov, Konstantin P. author Gutfleisch, Oliver author 2022-12-12T17:53:53Z 2022-12-12T17:53:53Z 2017-05-29 2022-12-12T17:53:53Z The unavoidable existence of thermal hysteresis in magnetocaloric materials with a first-order phase transition is one of the central problems limiting their implementation in cooling devices. Using minor loops, however, allows achieving significant cyclic effects even in materials with relatively large hysteresis. Here, we compare thermometric measurements of the adiabatic temperature change Delta T-ad and calorimetric measurements of the isothermal entropy change Delta S-T when moving in minor hysteresis loops driven by magnetic fields. Under cycling in 2 T, the Ni-Mn-In-Co Heusler material provides a reversible magnetocaloric effect of Delta S-T(rev) = 10.5 J kg(-1) K-1 and Delta T-ad(rev) = 3.0 K. Even though the thermodynamic conditions and time scales are very different in adiabatic and isothermal minor loops, it turns out that after a suitable scaling, a self-consistent reversibility region in the entropy diagram is found. This region is larger than expected from basic thermodynamic considerations based on isofield measurements alone, which opens new opportunities in application. Published by AIP Publishing. Ciència dels materials Aliatges Propietats magnètiques Materials science Alloys Magnetic properties Reversibility of minor hysteresis loops in magnetocaloric Heusler alloys