Magnetocaloric Properties of Rare-Earth-Free Mn27Cr7Ni33Ge25Si8 High-Entropy Alloy

The magnetic and magnetocaloric properties of a new Mn
₂₇
Cr
₇
Ni
₃₃
Ge
₂₅
Si
₈
high-entropy alloy (HEA) were investigated. The crystal structure is characterized through multiphase Rietveld refinement of X-ray diffraction data. The structure of the HEA is orthorhombic in the Pnma space group. Arrott plots indicate that the ferromagnetic-paramagnetic phase transition is of second order. The maximum magnetic entropy change is 2.49 J·kg
^-1
·K
^-1
, among the highest reported for alloys that do not contain rare earth elements.