Abstract
The results on the investigation of near-surface micro-magnetic structure of the as-cast and annealed at 550°C for 1hr FeCuNbSiB ribbons are presented. The measurements were performed by using of the magneto-optical micro-magnetometer having the spatial resolution up to ∼0.3μm. The as-cast samples were amorphous and the annealed samples had nanocrystalline structure with typical grain sizes of 10-12 nm. The dispersion of magnetic anisotropy was discovered in the studied samples. As result, their local magnetic properties were inhomogeneous. The linear size of the magnetic inhomogeneities in the as-cast and annealed samples was equal to ∼ 120-150 and ∼ 50-70 μm, respectively. It was established that in the annealed samples the local initial magnetic permeability increases and the coercivity decreases (up to 10 times) with respect to those of the ascast samples.
