Magnetic properties and magnetocaloric effect in Fe90-xNixZr10 alloy ribbons.

We report magnetic properties and magnetocaloric (MC) effect in Fe90-xNixZr10 (x = 0, 5, 10, and 15) alloy ribbons prepared by rapid-quenching method. We found the Curie temperature (TC) of the alloy ribbons depends strongly on Ni-doping concentration (x) increasing from 245 K for (x = 0), through 306 K (for x = 5) up to TC = 403 (for x = 15). Also, the dependence of the maximum magnetic entropy change (|ΔSmax|) on Ni content was readily apparent. Indeed, for the x = 0 and 5 samples that have TC around room temperature, the |ΔSmax| values increment under magnetic field changes of 10, 20, and 40 kOe was found to be as high as 0.87, 1.76, and 3.04 J·kg-1·K-1 for x = 0, and 1.03, 1.90, and 3.26 J·kg-1·K-1 for x = 5, respectively. These values correspond to refrigerant capacity in the range of 86-334 J·kg-1 and are comparable to other known MC materials. High magnetocaloric performance in rare-earth-free non-expensive metallic alloys indicates that these materials could be competitive candidate for active magnetic refrigeration at room temperature. [ABSTRACT FROM AUTHOR]