Magneto-caloric effect of FeₓZrᵧB₁₀₀₋ₓ₋ᵧ metallic ribbons for room temperature magnetic refrigeration

Abstract

Among various amorphous magnetic materials, even though Fe-based materials do not have high magnetocaloric effect (MCE), their advantages of tunable Curie temperature (TC) and low cost have attracted considerable attention in regard to room temperature magnetic refrigeration applications. With the aim of enhancing the MCE, the influence of boron addition on Fe-based amorphous materials was investigated in this study. Fe94−xZr6Bx (x=5, 6, 8 and 10), Fe91−yZr9By (y=3, 4, 5, 6, 8 and 10) and Fe89−zZr11Bz (z=3, 4, 5, 6, 8 and 10) specimens were made in ribbon form and their magnetocaloric effect was investigated. The Curie temperature (TC) of all three series of ribbons underwent an almost linear increase, and the peak magnetic entropy change, |ΔSMpeak| (obtained in a magnetic field of 1.5 T), generally increases with increasing boron content. The results further show that the Fe86Zr9B5 ribbon exhibits a relatively large |ΔSMpeak| value of 1.13 J/kgK at 330 K and a large refrigerant capacity value of 135.6 J/kg under 1.5 T. On the basis of these results, although there is still much scope for improvement before totally replacing the conventional cooling method, the Fe-based amorphous ribbon can be seen as a promising magnetocaloric material for room temperature magnetic refrigeration applications.