Magnetostriction Measurements for Amorphous Wires

Measurements of the saturation magnetostriction constant ¿3 of amorphous wires have been difficult using conventional techniques, due to their very small diameters (10~125 ¿m). This paper describes the stable measurement of the magnetostriction of amorphous wires, using a magnetization rotation model and applying a compressive stress to positive-magnetostriction wires and a tensile stress to negative-magnetostriction wires. A value for ¿S of 35 ppm was obtained for an as-prepared Fe77.5Si7.5B15 wire at room temperature.