Effect of annealing on magnetic properties and Giant magnetoimpedance effect of amorphous microwires

We studied Giant magnetoimpedance (GMI) effect and magnetic properties of amorphous Fe-Co rich as-prepared and annealed microwires. We measured the GMI magnetic field and frequency dependences, hysteresis loops and domain walls (DWs) dynamics of composite microwires produced by the Taylor-Ulitovski technique. We observed that these properties can be tailored either controlling magnetoelastic anisotropy of as-prepared CoFeBSiC microwires or controlling their magnetic anisotropy by heat treatment. High GMI effect has been observed in as-prepared Co-rich microwires. High DW velocity and rectangular hysteresis loops we observed in heat treated Co-rich microwires. We observe increasing of the DW velocity under stress in some annealed samples.