Ribbon-form Sendust alloy made by rapid quenching methods

Ribbon-form Sendust was prepared by a roll quenching method. The size of the ribbon was 20∼110 μm thick, 2∼8 mm wide and 5∼10 m long. The normal direction of the ribbon plane was parallel to the [100] as well as the [110] axes, and no preferential directions exist within the ribbon plane. Vickers hardnessH _v of the as-prepared ribbon was 563±7, decreased with increasing the annealing time and became almost constant. The minimum bending diameter of the as-prepared ribbon was 8 mm and increased gradually with increase of the annealing time. Initial permeability of the 84.80 Fe·9.50 Si·5.70 Al ribbon was about 34,000 in the frequency range from 1 to 3kHz and decreased to be 10,000 at 85 kHz. The permeability of the molded core in a resin was about 21,000 in the frequency range from 1 to 3 kHz.