Effect of annealing on anisotropy field in Fe84Zr7B8Cu1 amorphous ribbons evaluated by giant magnetoimpedance

The magnetoimpedance (GMI) profiles were measured in ${\mathrm{Fe}}_{\mathrm{84}}{\mathrm{Zr}}_{\mathrm{7}}{\mathrm{B}}_{\mathrm{8}}{\mathrm{Cu}}_{\mathrm{1}}$ amorphous ribbons annealed at various temperatures. The anisotropy field evaluated from GMI profiles changed sensitively with annealing temperature. The decreasing $H_k$ and increasing magnitude of GMI with the annealing temperature were ascribed for by the increase of magnetic softness, while the increasing $H_k$ and decreasing magnitude of GMI for the further increment of annealing temperature was associated with the microstructural change due to the annealing.