Magnetocaloric effect in melt-spun FePd ribbon alloy with second order phase transition

Magnetic entropy change and refrigerant capacity for an applied magnetic field variation of 1.5 T have been determined in the temperature range of 293–700 K for the as-quenched polycrystalline Fe73.2Pd26.8 melt-spun ribbons alloy. Samples show a major magnetic phase with the fct crystal structure and a Curie temperature of 553 K, at which a second order magnetic phase transition occurs. A maximum magnetic entropy change of 1.04 J kg−1 K−1 was achieved at 550 K, while the maximum refrigerant capacity of 108 J/kg is attained at the applied field of 1.5 T. The field dependence of the magnetic entropy change for this material follows the phenomenological universal curve and at the temperature of the peak corresponds to a large field independent exponent of n = 0.84. Extrapolated value of field depending RCArea at 5 T reach above 300 J/kg, which is comparable to that of some of the best-known Fe-doped GdSiGe coolant compounds.

Research highlights▶ Biphasic FePd polycrystalline melt-spun ribbons exhibit a second order phase transition with a TC of 553 K. ▶ Field dependence (up to 1.5 T), on magnetic entropy change exhibits a maximum of 1.04 J kg−1 K−1 at 550 K. ▶ Scaling of the field depending magnetic entropy change with the model of the universal curve shows a large field independent exponent value of n = 0.84. ▶ The maximum refrigerant capacity value of 108 J/kg is obtained at 1.5 T. ▶ Extrapolated value for the field dependence of RCArea at 5 T reaches 314 J/kg, similar to the corresponding one for GdSiGeFe.