Reduction of hysteresis loss and large magnetic entropy change in the Na Zn13 -type LaPrFeSiC interstitial compounds

Magnetic properties and magnetic entropy change of the Na Zn13 -type La0.5 Pr0.5 Fe11.5 Si1.5 Cx compounds have been investigated. Both the lattice parameter and the Curie temperature increase linearly with increasing carbon concentration. The maximum hysteresis loss at TC reduces remarkably from 94.8 Jkg for x=0 to 23.1 Jkg for x=0.3 because of the weakening of the itinerant electron metamagnetic transition. However, the magnetic entropy change remains at the large values of 32.4 Jkg K for x=0 and 27.6 Jkg K for x=0.3 under a field change of 0-5 T, which implies that a large magnetocaloric effect and a small hysteresis loss have been simultaneously achieved in the La0.5 Pr0.5 Fe11.5 Si1.5 Cx carbides.