Magnetocalorific effect in amorphous and partially-crystallized Fe-Zr-Nb-Cu-B alloy

This paper presents the results of an investigation into the: microstructure, magnetic properties and influence of annealing temperature on the magnetocaloric effect of Fe82Zr7Nb2Cu1B8 alloy in the as-quenched and partially crystalline state. The microstructure was investigated using Mössbauer spectroscopy. The magnetocaloric effect was observed as a change in the magnetic entropy, which was calculated from isothermal magnetization curves. Fullyamorphous Fe82Zr7Nb2Cu1B8 alloys, in the as-quenched state, exhibit a Curie temperature equal to (340±5) K. The transmission Mössbauer spectrum for the as-quenched Fe82Zr7Nb2Cu1B8 alloy is typical for weak ferromagnets with the average hyperfine field of 9.86(2) T. For this alloy in the as-quenched state, the changes in maximum magnetic entropy occur near the Curie points and are equal to 0.95 J/(kg K). Also, the maximum magnetic entropy changes decrease after partial crystallization