The effects of Ag addition on the magnetic properties of an Fe/sub 87.3/Zr/sub 5.9/B/sub 6.5/Ag/sub 0.3/(at %) amorphous alloy

The magnetic properties of an Fe/sub 87.3/Zr/sub 5.9/B/sub 6.5/Ag/sub 0.3/ (at.%) amorphous alloy have been investigated as a function of annealing temperatures in order to know its potential applicability as core material for high-frequency applications. A very excellent soft magnetic material was developed. The amorphous alloy, which was annealed at T/sub a/=400/spl deg/C, exhibited very high initial permeability (/spl mu/i) of 287 000 at 1 kHz and 2 mOe, very low coercivity (H/sub c/) of 15 mOe, and low core loss (W/sub c/) of 50 W/kg at 100 kHz and 0.1 T, respectively. It is notable that the values obtained in the present study are the best magnetic properties among various kinds of Fe-based soft amorphous materials reported up to now. The reason for the achievement of good soft magnetic properties is presumably due to the homogeneous formation of very fine /spl alpha/-Fe clusters of size 2-3 nm in an amorphous matrix, which can be deduced from an increase of resistivity and transmission electron microscopy (TEM) observation. The very fine /spl alpha/-Fe clusters embedded in an amorphous matrix, had a great influence on the reduction of magnetostriction and refinement of the magnetic domain.