FORMATION AND MAGNETIC-PROPERTIES OF Y2(FE0.8GA0.2)17CX COMPOUNDS

The alloys Y2(Fe0.8Ga0.2)17Cx (x = 0-2.5) with the rhombohedral Th2Zn17 phase were prepared by arc melting. The lattice parameters and the unit-cell volumes derived from x-ray-diffraction measurements increase linearly with the carbon content x. The Curie temperature T(c) increases at first with increasing carbon concentration x, shows a maximum value of 558 K at about x = 1.0, then decreases with x. The saturation mapetization at 1.5 K and the Fe magnetic moment have a slight change with the interstitial carbon content. The dilution of Fe by nonmagnetic Ga decreases the saturation mapetization and the Fe magnetic moment.