Comparison of Stress-Impedance Effect in Amorphous Ribbons with Positive and Negative Magnetostriction

Area of Science:

• Materials Science
• Condensed Matter Physics
• Magnetism

Background:

• The stress-impedance (SI) effect, also known as the Villari effect, describes changes in magnetic properties of magnetostrictive materials under applied stress.
• Amorphous magnetic ribbons are promising materials for sensor applications due to their unique magnetic and mechanical properties.

Purpose of the Study:

• To investigate the SI effect in iron- and cobalt-based amorphous ribbons with varying magnetostriction coefficients.
• To analyze the relationship between applied tensile stress and impedance change.
• To identify the most suitable material for developing precise small force sensors.

Main Methods:

• Tensile stress was applied to amorphous ribbons using a dead weight tester.
• The change in impedance was measured as a function of applied stress.
• The Villari reversal point and its dependence on driving current frequency were observed.
• Magnetoelastic hysteresis was analyzed.

Main Results:

• Significant differences in SI characteristics were observed between iron- and cobalt-based ribbons.
• A stress-impedance analog of the Villari reversal point was identified.
• The Villari reversal point exhibited dependence on the driving current frequency, manifesting at different stress values.
• Magnetoelastic hysteresis provided insights into material behavior under stress.

Conclusions:

• The study successfully characterized the SI effect in amorphous ribbons with varying magnetostriction.
• The Villari reversal point's frequency dependence offers a method for tuning sensor sensitivity.
• Based on SI characteristics and magnetoelastic hysteresis, a specific amorphous ribbon material was selected as most appropriate for precise small force sensor development.