Magnetoimpedance Properties of Amorphous CoFeSiB Wires in a Wide Frequency Range: Focus on Sensor Applications

Abstract

The magnetic properties and specific features of giant magnetoimpedance in rapidquenched amorphous wires of composition (Co_0.94 Fe_0.06 )_72.5Si_12.5 B₁₅ are investigated. The working interval and sensitivity to changes in an external quasistatic magnetic field have been calculated for the alternating current frequencies from 1 MHz to 1 GHz. Parameters that are optimum for using such wires as sensitive elements in magnetic field sensors have been calculated, and the probe sensitivity to the external magnetic field has been determined. A sensor prototype was designed that, when tested, confirmed the possibility of using the giant magnetoimpedance in sensors based on amorphous CoFeSiB wires for flaw detection.