Optimization of GMI Effect and Magnetic Properties of Co-Rich Microwires by Joule Heating

Joule heating of the Co-rich glass-coated microwire allows remarkable improvement of magnetic softness and giant magnetoimpedance effect. At optimal Joule heating conditions we observed GMI ratio up to 650%, low magnetic anisotropy field of about 25 A/m and coercivity of about 2 A/m. Observed experimental dependencies are discussed considering various factors affecting the magnetic properties of studied microwire upon Joule heating: induced magnetic anisotropy, internal stresses relaxation and radial distribution of magnetic anisotropy.