Room-Temperature Magnetocaloric Properties of (La1-Nd )2Fe10.7Mn0.3Si2H

Magnetocaloric properties of (La1-xNdx)2Fe10.7Mn0.3Si2Hy (x = 0.1 and 0.2) are evaluated to develop a room-temperature magnetic refrigerant. While Nd which is introduced to reduce the thermal hysteresis has a negligible effect on magnetic properties, the partial replacement of Fe with Mn converted the first-order magnetic transition to a second-order and TC is reduced by 50 K to near room temperature. The peak entropy change, ΔSM|pk values are 10.4 J kg-1 K-1 (at 290 K) for x = 0.1 and 10.6 J kg-1 K-1 (at 286 K) for x = 0.2. with μ0∆H = 3 T. The maximum values of the adiabatic temperature change, ΔTad are 4.11 K (at 283 K) for x = 0.1 and 4.05 K (at 289 K) for x = 0.2 with μ0∆H = 1.4 T. Because TC can be shifted by the addition of Mn to room temperature, this series of compounds can be used as an efficient magnetic refrigerant or a combination as a composite refrigerant for an active magnetic refrigeration cycle.