Tunable Curie temperature around room temperature and wide temperature span of magnetic entropy change in (Fe1−xMnx)2Y compounds

Abstract

The structure, Curie temperature (TC) and magnetic entropy change (ΔSM) of (Fe1−xMnx)2Y (x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6) compounds were investigated by x-ray powder diffraction (XRD) and magnetization measurements. All compounds crystallize in single phase with cubic MgCu2-type structure and present second-order phase transitions from ferromagnetic to paramagnetic state at TC. The substitution of Mn for Fe in the Fe2Y system results in the drastic decrease of TC from TC = 519 K for x = 0 to TC = 78 K for x = 0.6. The maximum values of ǀΔSMǀ as well as broad working temperature spans are obtained under a field change from 0 to 5 T, which are 1.65, 1.27 and 1.17 J kg−1·K for x = 0.3, 0.4 and 0.5, respectively. The corresponding relative cooling power (RCP) values are evaluated to be 90.29, 84.98 and 63.29 J kg−1. The present results may give some clue for searching new materials with large magnetocaloric effect.