By suppressing the growth of impurities, a melt spinning method was successfully applied to the synthesis of typical 1 : 2 : 2 layered CeMn 2 Si 2 and AlFe 2 B 2 compounds. X-ray diffraction analysis showed that CeMn 2 Si 2 and AlFe 2 B 2 had good purity and crystallized in ThCr 2 Si 2 -and AlFe 2 B 2 -type structures, respectively. The differences among three 1 : 2 : 2-type structures were also analyzed. The magnetic properties were investigated by magnetic measurements and electronic structure calculations. It was found that the Fe moment of AlFe 2 B 2 reaches 1.32 μ B at 5 K, which fits well with the calculated result of 1.44 μ B at 0 K, and that the isothermal magnetic entropy change reaches 7.2 J kg %1 K %1 at 5 T, which shows great potential for room-temperature refrigeration applications.

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In the past decade, Mn rich Ni-Mn based alloys have attained considerable attention due to their abundant physics and potential application as multifunctional materials. In this paper, polycrystalline Ni50Mn38−xPdxSn12 (x = 0, 2, 4, 6) Heusler alloys have been prepared, and the martensitic phase transformation (MPT) together with the shape memory effect and the magnetocaloric effect has been investigated. The experimental result indicates that the MPT evidently shifts to a lower temperature with increase of Pd substitution for Mn atoms, which can be attributed to the weakness of the hybridization between the Ni atom and excess Mn on the Sn site rather than the electron concentration. The physics properties study focused on the sample of Ni50Mn34Pd4Sn12 shows a good two-way shape memory behavior, and the maximum value of strain Δ L/L reaches about 0.13% during the MPT. The small of both entropy change Δ ST and magnetostrain can be ascribed to the inconspicuous influence of magnetic field induced MPT.