The magnetic anisotropy of cold-rolled and as-quenched amorphous (Fe1?x Ni x )78Si10B12 alloy systems

In order to make clear the origin of magnetic anisotropy of amorphous alloys produced by a single roller quenching method, the composition dependence of the in-plane magnetic anisotropy of cold-rolled and as-quenched amorphous (Fe₁− _x Ni _x )₇₈Si₁₀B₁₂ alloy systems was studied at room temperature. The twofold in-plane magnetic anisotropy constantK _u of cold rolled and as-quenched specimen decreases with increase inx at the Fe-rich side, and increases drastically at aboutx=0.2. Beyondx=0.25,K _u decreases gradually with further increase inx. From this study, it is emphasized that there is a clear correspondence between the atomic ratio of Fe to Ni at which the anomaly in magnetic anisotropy of the amorphous alloy occurs and the position of the fcc/bcc phase boundary in the Fe−Ni metal alloy system.