Magnetic Annealing effect on Magnetoelastic Ribbons for Remote Viscosity Sensors

Abstract

This letter describes the effect of annealing for magnetoelastic ribbon as a remote viscosity sensors. Magnetoelastic ribbon was placed in an AC magnetic field generated by an external coil. The vibration of the ribbon could be monitored with a pickup coil and it reached its maximum value at the mechanical resonant frequency based on the magnetostriction effect. Non-uniform stress and dispersed magnetic anisotropy direction of ribbon causes instability of mechanical resonant frequency. This stability was markedly improved by annealing the ribbon at 380 °C for 10 min. in transverse magnetic field of 100 Oe.