Magnetic study of amorphous Fe91-xYxZr9 alloys

Amorphous Fe91-xYxZr9 alloys (x = 0, 5, 8 and 10) have been prepared by the melt-spinning method and their magnetic properties have been studied. The thermomagnetization curve is found to obey the Bloch law, M(T) M(0)(1 - BP3/2); magnetic moment of the Fe, spin wave stiffness constant D and exchange constant A were calculated from the experimental results. The D derived is composition dependent and increases with increasing Y contents. From an analysis of the approach to saturation in magnetization, the local random anisotropy constant K-L has been extracted. It is found that K-L decreases with increasing Y concentration. This result suggests that the substitution of Fe with Y seems to favor the increase of magnetic order by reducing the randoin anisotropy. (C) 2002 Elsevier Science B.V. All rights reserved.