Magnetic and magnetocaloric properties of [formula omitted

Abstract

We investigate the crystal, magnetic and magnetocaloric properties of the Fe5−xMnxSn3 series (0≤x≤5) from X-ray diffraction and DC magnetization experiments. The alloys crystallize with the lacunar Ni2In type of structure (P 63/mmc). The diffraction patterns of the richer Fe alloys (x≤2) contain tiny superstructure lines due to ordering of T atoms and vacancies within the partially filed 2d position. The Curie temperatures decrease in a non-monotonous manner with the Mn content from 544K in Fe5Sn3 down to 190K in Fe1Mn4Sn5, before increasing again up to 219K in Mn5Sn3. While most of the alloys behave as simple ferromagnets, low-field thermomagnetization data show that the Fe5−xMnxSn3 alloys with intermediate compositions (x=2.5 and 3) undergo two close ferromagnetic-like transitions. The magnetocaloric effect is of moderate magnitude (~1Jkg−1K−1 for μ0ΔH=2T). The results are compared with previously published data and briefly discussed in view of potential high-temperature magnetocaloric applications.