Giant magnetoimpedance effect in as quenched Fe89-xZr7B4Cux (x=1.0-2.5) ribbons

The giant magnetoimpedance (GMI) effect in as-quenched FeZr7B4Cux (x=1.0-2.5) ribbons is reported. The as-quenched FeZr7B4Cux (x=1.0-2.5) ribbons were prepared by the vacuum melt-spun processes withthe quenching speed of 37m/s. The magnetoimpedance measurement were performed at room temperature, where the current flows through the length of the ribbons in the direction parallel to the dc fields. Results show that values Z (impedance), R (resistance) and X (reactance) forboth H=0A/m and H=5127A/m increases with increasing ac frequency. This can be explained by the skin effect mechanism. The GMI effect almostcan not be found in the Cu content (mass fraction) range x 1.5%. With increasing Cu content x > 1.5%, the GMI effect become evident for as-quenched FeZr7B4Cux (x=1.0-2.5) ribbons. GMI ratio (Z(0)Z(H)/Z(0)) in as quenched Fe86.5Zr7B4Cu2.5 with melt-spun quenching speed of canreaches 33.69% at H=5127A/m. This indicated that good GMI properties can be also obtained in as-quenched FeZrBCu ribbons without annealing.