Magnetostriction Oscillator

an electromechanical or electroacoustical converter in which the energy of a magnetic field is converted into the energy of mechanical oscillations, and vice versa, because of the reversible effect of magnetostriction. The device is used as a radiator or receiver of ultrasound and in measurements of vibrations of various structures and buildings, as well as in filters and stabilizers of various electric and radioelectronic devices.

A magnetostriction oscillator consists of a core of magnetostrictive material (nickel, special alloys, ferrites, and so on) and a winding. The converter element is the core itself, in which the relative elongation Δl/l during magnetization attains values of 10³-10^-5, where l is the length and Δl is the elongation of the core during magnetization. At frequencies of 10-100 kilohertz, the use of magnetostriction oscillators made from metallic materials, which have higher mechanical strength and saturation induction, is best. Magnetostriction oscillators in hydroacoustic and ultrasonic devices are most frequently rod- or ring-shaped but are sometimes made in the form of thin-walled tubes that oscillate longitudinally; the sound is received and emitted by the end surfaces of the magnetic circuit.