The magnetic properties of ultrathin Fe-Al-Nb-B-Cu nanocrystalline alloys

The magnetic properties of ultrathin Fe/sub 75/Al/sub 4/Nb/sub 5/B/sub 12/Cu/sub 1/ nanocrystalline alloy ribbons with 9 /spl mu/m thickness and the effect of Al additions to Fe-B-Nb-Cu alloy for improving the high-frequency magnetic properties were investigated. It was found that the effective permeability at frequencies over 100 kHz was higher and the core loss was lower for the composition Fe/sub 75/Al/sub 4/Nb/sub 5/B/sub 12/Cu/sub 1/ alloy. Moreover, the reduction of the ribbon thickness to 9 /spl mu/m was very effective in improving their permeability and the core loss characteristics up to the MHz frequency range.