Effects of creep-induced anisotropy on circumferential magnetization in non-magnetostrictive wires

Abstract

The effects of applied tensile stress, σ, on the magnetic properties of stress-annealed amorphous wires (Co 0.94Fe 0.06) 72.5B 15Si 12.5 were investigated. Stress-current annealing was performed at various tensile stresses, σ, in the range 0–800 MPa. Circular magnetization curves were obtained from the complex impedance response of the wire, submitted to currents between 0.01 and 30 mA (rms) at a frequency of l kHz. A transverse anisotropy is developed by these thermal treatments, which results in a continuous increase in the axially measured anisotropy field with σ. The circumferential magnetization curves, however, exhibit two different behaviors of the pinning field, separated by a critical tensile stress (450 MPa). These results are interpreted in terms of the changes produced on the domain structure by stress annealing.