Circumferential magnetization curves of Co-rich amorphous wires under tensile stress

Abstract

Circumferential magnetization curves were obtained for low, negative magnetostriction amorphous wires of nominal composition (Co0.94Fe0.06)72.5B15Si12.5, under tensile stress up to 250 MPa, by using the magnetoimpedance effect. The various magnetization processes, i.e., spin rotation, domain wall bulging, and domain wall displacement were resolved by frequency measurements in the 5 Hz–13 MHz range, and by varying the applied field amplitude between 0.28 and 12 A/m (root mean square). The results show that reversible magnetization processes (domain wall bulging and spin rotation) are damped by tensile stress, while the irreversible process (domain wall displacement) is enhanced by stress. These results are interpreted in terms of an increase in anisotropy and a reorienting of magnetization in circumferential domains, both as a result of the stress-induced anisotropy.