STUDY OF THE MAGNETOCRYSTALLINE ANISOTROPY OF YFE(12-X)MO(X) AND YFE(12-X)MO(X)N(Y) (X=1-3, Y-SIMILAR-OR-EQUAL-TO-1)

The magnetocrystalline anisotropy of YFe12-xMox and YFe12-xMoxNy (x = 1-3, y congruent-to 1) have been investigated by x-ray diffraction and the singular point detection technique. The uniaxial anisotropy of the YFe12-xMox series decreases with increasing Mo concentration with a clear turning point at about x = 1.6. The anisotropy characteristic of the nitride YFe12-xMoxNy changes into a canted-type anisotropy for x < 1.5 and a planar anisotropy for x greater-than-or-equal-to 1.5. The anisotropy reduction for YFe12-xMox is mainly due to the substitution of Mo atoms on the 8i sites, while the further change in anisotropy for YFe12-xMoxNy may be due to a change in the 3d orbital moment or to a change in crystal-field interaction by the interstitial N atoms.