Magnetocaloric effect in amorphous and nanocrystalline Fe81-xCrxNb7B12 (x=0 and 3.5) alloys

作者：Skorvanek I^*; Kovac J; Marcin J; Svec P; Janickovic D

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2007, 449: 460-463.

DOI：10.1016/j.msea.2006.02.353

• magnetocaloric effect
• magnetic entropy
• soft magnetic alloys
• nanocrystalline materials

The magnetocaloric effect in series of amorphous and nanocrystalline Fe81-xCrxNb7B12 (numbers indicate at.%, x = 0 and 3.5) samples has been studied by evaluating the magnetic entropy changes, Delta S-m, from magnetization data. The addition of chromium to the ternary Fe81Nb7B12 alloy results in a decrease of the Curie temperature of amorphous sample, T-c(am), from 363 to 279 K, which makes this Cr containing alloy an interesting material for potential magnetic refrigeration applications near room temperature. Upon magnetic field change from 0 to 0.7 T, the maximum entropy change located at the T-c(am) of non-crystallized ribbons has been found to be about 0.7 J kg(-1) K-1. The progressive nanocrystallization of amorphous samples results in a more diffuse ferro-/paramagnetic transition, which causes a decrease of the magnetic entropy changes and at the same time the Delta S-m peak becomes broadened. The observed Delta S-m values compare favorably with other amorphous Fe-based alloys.

• 出版日期2007-3-25