Magnetostrictive Ferrites with Small Change in Coupling Coefficient from 0° to 20°C

Abstract

Ferrite materials which possess electromechanical coupling coefficients of 30% or more over the temperature interval 0° to 20°C were developed by the control of the various anisotropies. A high order of temperature stability of the coupling coefficient was achieved by a new technique in which a number of ferrites are combined in a composite core structure. Composite transducers made by the technique emerge as single bodies adn not as a composite made up of discrete parts.