Table-like magnetocaloric effect of Fe88−xNdxCr8B4 composite materials

The narrow working temperature range due to the sharp magnetic entropy change |ΔSM| peak and large thermal or magnetic hysteresis restricts the practical application of magnetocaloric materials. In this work, the table-like magnetocaloric effect (MCE) was obtained in the multilayer composite of Fe88−xNdxCr8B4 alloys with various Nd substitutions for Fe (x=5, 8, 10, 12, and 15), which were prepared by arc-melting followed by melt-spinning. The substation of Nd was found to enhance the glass-forming ability. For the alloys with Nd substitution from 5 at% to 15 at%, the Curie temperature (TC) ranged from 322 K to 350 K and the peak value of |ΔSM| remained almost constant, 3.4-3.5 J/(kg K) under an applied field of 0-5 T. The composite with various Nd contents was prepared by stocking the ribbons layer by layer. The |ΔSM| of the composite approached a nearly constant value of ∼3.2 J/(kg K) in a field change of 0-5 T in a wide temperature span over 40 K, resulting in large refrigerant capacity value of >408 J/kg. This |ΔSM| value was much larger than the previous reported Fe-based amorphous composite Fe78−xCexSi4Nb5B12Cu1. This composite can be used as the working material in the Ericsson-cycle magnetic regenerative refrigerator around room temperature.