The effects of field annealing on the magnetic properties of FeSiB amorphous powder cores

Abstract The effects of transverse magnetic field annealing on the magnetic properties of Fe78Si9B13 amorphous powder cores were investigated. The cores annealed at 400 °C under an external transverse magnetic field of 0.5 T show an enhanced and stable effective permeability of 90 in the high frequency range up to 2 MHz. Meanwhile, the permeability was improved by about 5% and the core loss was decreased by about 10% compared to the core with zero field annealing, which is attributed to the relief of internal stress and the variation of domain structure. It also shows superior DC bias property with a “percent permeability” of 70% at an external field of 100 Oe. Transverse magnetic field annealing is an effective way to improve the soft magnetic properties of the amorphous powder cores. The improvement of soft magnetic properties of the Fe-based amorphous powder cores is encouraging for future applications as functional materials.