Stress annealing in Fe73.5Cu1Ta3Si13.5B9 amorphous alloy: Induced magnetic anisotropy and variation of the magnetostriction constant

Abstract

The effect of Joule heating anneals, carried out with the simultaneous application of a mechanical stress (stress-current annealing), on the anisotropy and magnetostriction of Fe73.5Cu1Ta3Si13.5B9 amorphous samples is investigated. As a result of these thermal treatments an uniaxial in-plane magnetic anisotropy, characterized by the constant Kσ, was induced in the samples. The dependence of Kσ on the annealing temperature shows a maximum around 450 °C which can be connected to the first stages of the crystallization process. From the measurement of the stress dependence of the magnetization work Wm, the magnetostriction constant λs of the as-quenched and thermally treated samples was also evaluated. The results obtained show how the presence of two phases in the partially crystallized material determines the magnetoelastic behavior of these samples.