Co rich metallic glasses as stress sensitive elements based on magneto-impedance effect

The attractive magnetic properties of Co-rich amorphous ribbons make this material suitable to observe the magneto-impedance (MI) effect. We report the dependence of All effect on external applied stress as a possibility of using this effect for stress sensors. A morphous ribbons of Vitrovac 6025 (Vacuumschmelze) were subjected to different processing techniques that change their saturation magnetostriction coefficients, obtaining impedance ratios around 4000% at a frequency of 1 MHz for the as quenched ribbon, and impedance variations of the order of 180 MPa/Omega for one of the treated ribbons.