Magnetocaloric effect in NaZn_(13)-type La_(1-x)Pr_xFe_(11.44)Si_(1.56) melt-spun ribbons

摘要

The influence of Pr content on structure, magnetic properties, and magnetic entropy changes of La_(1-x)Pr_xFe_(11.44)Si_(1.56) was investigated. X-ray diffraction analysis showed that the 1:13 phase with cubic NaZn_(13)-type structure was obtained by a short time annealing (1300 K and 3 h) in melt-spun ribbons, which in contrast requires much longer time annealing at high temperature to develop in the bulk alloy. The field-induced first-order transition was observed in the as-annealed ribbons, leading to the large magnetic entropy changes. The maximum magnetic entropy changes under a magnetic field of 5 T were about 14.3, 19.2, and 19 J/kg K for the ribbons with x=0, 0.1, and 0.2, respectively.