Surface Magnetic State of Amorphous Fe78Bi13Si9 Alloy Ribbons Investigated by Ferro Magnetic Resonance

The surface layers of iron-base amorphous ribbons formed by liquid quenching exhibit a large anisotropy which is reduced by surface polishing. Here, FMR was used to study the anisotropy separately in the roll and free sides of Metglas 2605-S2 amorphous ribbons before and after polishing. The results indicate that a large anisotropy exists primarily on the roll surface. When this side is polished large changes in both resonance field and anisotropy field at the free surface are observed.