Institute for Materials Research, National University of Mexico, P.O. Box 70-360, 04510, Mexico, D.F., Mexico
Abstract:
The unpinning or propagation field, hp, where domain walls are unpinned and start their displacement under the AC magnetic field of as-cast amorphous wires of nominal composition (Co94Fe6)72.5B15Si12.5, was determined for each torsion angle between –90° (counterclockwise) and +150° (clockwise) at a constant frequency of 1 kHz. A plot of hp as a function of torsion angle showed a sharp minimum at a torsion angle of +120. The results are interpreted in terms of the counterbalance effect of the torsion against the intrinsic helical anisotropy induced during the wire fabrication.