Application of a Magnetostrictive Alloy, Terfenol-D to Direct Control of Hydraulic Valves

The high strain (>1000ppm) and high force properties of a rare earth-iron alloy, Terfenol-D, make it attractive for application to direct control of hydraulic valves. Material properties of Terfenol-D are reviewed along with actuator designs for Terfenol-D driven valves. Principles concerning application of this material to valve technology in general are presented.