The easy formation of the monoclinic MCE phase in Gd5Si2Ge2 with the addition of Sn

The Gd5Si2Ge2 and Gd5Si2 − xGe2 − xSn2x (x ≤ 0.25) alloys were prepared by arc-melt method. The phase composition of each alloy has been investigated with the help of powder X-ray diffraction. Only the high temperature heat treatment could purify the phase of the as-cast Gd5Si2Ge2 prepared from commercial grade Gd and make it adopt in the monoclinic Gd5Si2Ge2-type single phase. With the addition of Sn, the monoclinic phase with large MCE is easy to form. In each as-prepared Gd5Si2−xGe2−xSn2x (x ≤ 0.25), the monoclinic Gd5Si2Ge2-type phase is dominant phase.