Characterization of amorphous FeZrB(Cu) alloys by the inductance spectroscopy method

Impedance spectroscopy measurements were carried out on amorphous ribbons o f nominal compositions Fe93-x-yZr7BxCuy (x=6,8 and y=0,1,2), in the frequen cy range of 5 Hz-13 MHz. Two different geometries were used for measurement s: a longitudinal one by using an 80-turn solenoid and the magnetoimpedance geometry, where the ac current flows through the ribbon itself. The obtain ed results showed a larger initial permeability value for longitudinal doma in walls, as compared with transverse ones. Results concerning the propagat ion field showed the opposite behavior. These results are interpreted in te rms of the short-range order arrangements of Fe atoms in these alloys, also known as "nanoamorphous demixing structures." (C) 2000 American Institute of Physics. [S0021-8979(00)25408-X].