Abstract:

The magnetic properties and magnetocaloric effect in Fe₄MnSi₃B_x compounds with x=0, 0.05, 0.10, 0.15, 0.20, 0.25 have been investigated. X-ray diffraction study shows that all these compounds investigated crystallize in the Mn₅Si₃-type structure with space group P6₃/mcm. Boron insertion in the host ternary silicide Fe₄MnSi₃ does not change the crystal symmetry, only leads to an increase of the lattice parameters, indicating the B atoms entered the interstitial sites. With increasing B content, the Curie temperature shifts to higher temperatures. The maximal magnetic-entropy changes of the Fe₄MnSi₃B_x compounds with x=0, 0.10 and 0.20 are about 1.8 J/(kg·K), 1.8~J/(kg·K) and 1.6~J/(kg·K), respectively, for a field change from 0 to 1.5 T.

Key words: Transition metal interstitial compounds, Magnetocaloric effect, Magnetic properties