The effective magnetic anisotropy in nanocrystalline Fe100-xSix alloys

The effective magnetic anisotropy in the nanocrystalline Fe100-xSx (x less than or equal to 25) alloys prepared by mechanical alloying was measured using the law of approach to saturation. It is found that the effective magnetic anisotropy constants K-eff decrease with increasing Si concentration, and are larger than those of the corresponding polycrystalline Fe100-xSix alloys. The Mossbauer patterns showed that the substitution of Si atoms for Fe ones is disordered. The high coercive force found in these alloys may be related to the high stress: and doping in grain boundaries. (C) 1999 Elsevier Science B.V. All rights reserved.