Effects of Magnetic Bias and Pre-stress on the Sensitivity of a Force Sensor Using Terfenol-D

Terfenol-D is a giant magnetostrictive material, which is used in actuators and sensors. To optimize its performance, operational conditions such as magnetic bias and pre-stress should be determined. In this paper, effects of these parameters on sensitivity of a Terfenol-D force sensor are investigated through theoretical and experimental study of Villari effect. To this end, model based on the coupled linear magnetomechanical constitutive equations is developed which leads to identify the effective parameters on the sensor’s sensitivity. Considering model outputs, experiments are performed to study magnetomechanical properties of Terfenol-D and obtain optimal magnetic field and mechanical pre-stress. Finally, the force sensor is simulated numerically based on optimized parameters.

Keywords:

Villari effect , Terfenol-D , Force sensor , Magnetic bias , Pre-stress