Magnetomechanical properties of single crystal Terfenol-D

Quasi-static and dynamic magnetomechemical measurements have been made on a twin-free <111> oriented single crystal of Tb0.27Dy0.73Fe2 (Terfenol-D). Unusually large values of dynamic strain coefficient, d(33), and magnetomechanical coupling coefficient, k(33), of 19.1 nm A(-1) and 0.83 respectively were recorded with an oscillating field of amplitude 500 A m(-1) rms at room temperature. The static magnetostriction saturated at 1688 x 10(-6), however 90% of this strain was achieved with field of 45 kA m(-1). The strain versus magnetization curves exhibit unusually linear regions, allowing confirmation that 71 degrees domain wall motion is primarily responsible for the high coupling coefficient of this material.