Magnetocaloric properties of the La0.7Pr0.3Fe13-xSix compounds

Magnetic entropy change Delta S-m, hysteresis loss and refrigerant capacity of NaZn13-type La0.7Pr0.3Fe13-xSix (1.5 <= x <= 2.0) compounds have been investigated. The Curie temperature T-C increases linearly with the increase of silicon concentration. Although the maximum value of Delta S-m under a field change of 0-5T decreases from 30.5 to 11.4J/kg K as x increases from 1.5 to 2.0, the hysteresis loss at T-C reduces remarkably from 89.2J/kg for x = 1.5 to zero for x = 2.0 because the increase of Si content can weaken the itinerant electron metamagnetic transition. The effective refrigerant capacity RCeff is maintained at high values of 362-439J/kg for a field change of 0-5T. This implies that a large Delta S-m and a high RCeff can be achieved simultaneously in the La0.7Pr0.3Fe13-xSix compounds. (C) 2009 Elsevier B.V. All rights reserved.