The Size Effects on High Frequency Magnetic Properties of Amorphous Wires

The frequency dependence of the permeability, jU^, in amorphous Co-Fe- Si-B wires was investigated as a function of the wire diameter, annealing temperature, tensile stress and drawing parameters. Results show that the level of μ
_i
and the critical frequency for holding μ
_i
constant depend mainly on the wire diameter, suggesting that eddy currents affect μ
_i
at high frequencies. It was also found that two-stage annealing, in which drawing followed by annealing was performed twice, results in an improved frequency characteristic of μ
_i