Improvement of soft magnetic properties for distinctly high Fe content amorphous alloys via longitudinal magnetic field annealing

The effects of longitudinal magnetic field annealing on soft-magnetic properties (SMPs) and magnetic domain structure of Fe(82.6-85.7)Si(2-4.9)B(9.2-11.2)P(1.5-2.7)C0.8 amorphous alloys with a distinctly high Fe content of 93.5-95.5 wt% for high Bs were investigated. It was found that longitudinal magnetic field annealing could improve soft-magnetic properties (SMPs) of amorphous alloys effectively, except the one with poor thermal stability. Superb magnetic properties containing a minimum coercivity of 0.8 A/m, a maximum effective permeability of 11 × 103 at 1 kHz and minimum core loss of 0.052 W/kg (at Bm = 0.9 T and f = 50 Hz) were successfully obtained. Domain structures were characterized with a Magneto-optical Kerr Microscope to unveil the mechanism of SMPs improvement. Stripe domains were observed in the annealed high Fe content amorphous alloy ribbons with optimal soft magnetic properties.