Magnetocaloric Properties of Mn{sub}5Sn{sub}(3-x)Ga{sub}x Alloys

摘要

We report on the crystal structure and the magnetic properties of Mn{sub}5Sn{sub}(3-x)Ga{sub}x alloys with x = 0.1, 0.3, 0.5, 1.0, and 1.5, which were investigated by means of X-ray powder diffraction and magnetization measurements in fields up to 5 T in the temperature range 5 to 360 K. These alloys have in common that they exhibit a temperature-induced ferriniagnetic phase transition. The results indicate that all samples crystallize in the hexagonal Ni{sub}2 In-type structure with space group P6{sub}3/mmc. The lattice parameters o and c of the Mn{sub}5Sn{sub}(3-x)Ga{sub}x decrease with increasing x, while the Curie temperature of these alloys increases with increasing x. All of the alloys exhibit a moderate magnetocaloric effect. Typical values are about 0.8 and 3 J/kgK at T{sub}c = 282 K for x = 1.5 in a magnetic field change from 0 to 1 T and 0 to 5 T, respectively.