Effects of Fe substitution on Mn2Sn alloy on its structural, magnetic and magnetocaloric properties

The effects of Fe substitution on Mn site of Mn2Sn compound was investigated by means of scanning electron microscopy with X-ray energy dispersive spectrometer, X-ray diffraction, magnetization and magnetocaloric measurements. The produced Mn2−yFeySn series (0.50 ≤ y ≤ 1.75) presented two phases, a major non-stoichiometric Mn2−xSn and a minor Mn3Sn, respectively, with Fe content replacing Mn in each phase. The lattice parameters a and c of Mn2−xSn and Mn3Sn phases decrease approximately linearly with Fe concentration while their transition temperatures increase covering a wide temperature range from 177 K to 546 K (major phase TC1) and 260 K to 704 K (minor phase TC2) resulting in alloys with two distinct values of TC. The magnetization measurements show a ferromagnetic coupling and saturation magnetization increases along the series. The heat flux analyses determined second order of magnetic transitions and magnetocaloric effect was calculated with |ΔS| around 1 J/kg.K. The cooling power was estimated in 85 J/kg. Both values were for µ0ΔH = 2 T. Thereby, for technological devices which have their efficient improved using layered materials, Mn2−yFeySn alloys are valid candidates since the association of its properties allow to yield a powerful magnetic and magnetocaloric material, and, besides, they are low cost, non-toxic, absent of rare-earth and easy to manufacture.