Nonuniform domain magnetization in CoFeSiB amorphous ribbons

Abstract

The low field ac susceptibility, χ=χ′−jχ′′, and domain structures of as-cast, stress relieved, and field annealed CoFeSiB amorphous ribbons are studied in the remanence state. An eddy current loss analysis is made based on a model which combines the contributions of domain wall displacements (DWD) and domain magnetization rotations (DMR). It is found that although having similar longitudinal bar domain structures, χ of the field annealed ribbon is due to DWD, but it is dominated by DMR for the first two, which indicates a nonuniform magnetization in the domains.