Torsion-Impedance in Soft Magnetic Amorphous and Nanocrystalline Wires

Abstract

The measurements of magneto-impedance,, have been performed, at the frequency f = 1 MHz, on amorphous and nanocrystalline wires under the application of torsion stress ( = 0-125 rad/m). At , exhibit single-peak due to the axial easy direction of the wires. The torsion-impedance,, is defined as the impedance change with at the condition of the axial field H = 0. We found that at the low torsion , shows a maximum at = 0.87 and 5.23 rad/m for the amorphous and the nanocrystalline samples, respectively; with increasing ,of the amorphous wire decreases monotonously and tends to the saturation, but of the nanocrystalline sample shows two more peaks at = 70.65 and 104.67rad/m. These results have been discussed considering the modification of domain structure by the applied torsion.