Stable magnetocaloric effect and refrigeration capacity in Co-doped FeCoMnZrNbB amorphous ribbons near room temperature

Abstract The Fe-based amorphous alloys are promising candidates for magnetic refrigeration due to their large magnetocaloric effect, outstanding mechanical property and high electrical resistivity. In this paper, the influence of Co addition on the magnetocaloric effect and refrigeration capacity has been studied for Fe 82− x Co x Mn 4 Zr 8 Nb 2 B 4 ribbons. X-ray diffraction patterns indicate that the Co-doped ribbons are amorphous. The Curie temperature can be adjusted from 271 to 363 K with the Co atomic concentration changing from 2 to 8. Favorably, both isothermal entropy change (Δ S T ) and refrigeration capacity ( RC ) remain nearly the same magnitude for the Co-doped ribbons. For a field change of 3 T, the maximum −Δ S T is about 1.7 J/kgK and the RC is about 115 J/kg for a temperature span of 80 K. The stable magnetocaloric effect and refrigeration capacity near room temperature reveals that the Co-doped amorphous ribbons may be considered as refrigerants for magnetic refrigeration.