Elastic and magneto-elastic modeling of Galfenol nanowires

This paper presents a magneto-elastic model developed by coupling a finite element elastic and magnetic formulations with an energy based probabilistic magnetostrictive model. Unidirectional coupled model is presented first for both sensor and actuator applications and then a fully coupled bidirectional model is developed. The unidirectional sensor model was validated against experimental results for a 1.58 mm diameter and 32.74 mm long Galfenol cantilever beam. The model was further used to investigate the response of Galfenol nanowire array that will be used in a nanowire acoustic sensor. Model predictions suggest that differences in the phase of bending motion of nanowires in an array will not produce a significant effect on the magnetic response of the array. It also predicts that the response of a single nanowire can be measured by a magnetic sensor with active measurement area much larger than the nanowire dimensions.