Effect of dc-Joule-heating thermal processing on magnetoimpedance of Fe72Al5Ga2P11C6B4 amorphous alloy

Abstract The effect of multistep dc-Joule-heating thermal processing on magnetoimpedance (MI) of Fe 72 Al 5 Ga 2 P 11 C 6 B 4 ribbons is presented. After material optimization significant increase of MI response up to value Δ Z / Z≈ 55% as well as sensitivity of about 6%/kA/m (for H ⩽3–4 kA/m), were recorded in still amorphous samples at driving frequencies 2–3 MHz. On-line and post-annealing electrical resistivity together with Mossbauer spectra analysis and frequency dependence of the penetration depth were used for characterization of MI improvement.