Giant refrigerant capacity in equi-atomic HoErGdCuNi amorphous ribbons

Abstract

The microstructure, cryogenic magnetic properties, magneto-caloric effect (MCE) and refrigeration performance of equi-atomic HoErGdCuNi ribbons have been investigated. Fully amorphousized structure with uniform distribution for all constituent elements is obtained. A table-like MCE that covers the temperature region from liquid nitrogen to liquid hydrogen is observed, which leads to a giant refrigerant capacity. Accordingly, the maximum magnetic entropy change (-ΔSMmax), temperature-averaged entropy change [TEC(10)] and refrigerant capacity (RC) are 15.8 J/kgK, 15.7 J/kgK and 903 J/kg, respectively, at the magnetic field change (ΔH) of 0–7 T. The equi-atomic HoErGdCuNi amorphous ribbons with good MCE parameters especially those with large RC values, are an attractive candidate for cryogenic magnetic refrigeration materials.