Magnetostrictive Devices

Magnetostrictive materials exhibit coupling between magnetic and mechanical energies. This bidirectional energy exchange can be employed for actuation, sensing, and energy harvesting. All ferromagnetic materials exhibit the magnetostrictive effect, but only certain iron–rare earth alloys, iron–gallium alloys, amorphous metals, and iron‐ aluminum alloys exhibit sufficiently high magnetostriction for commercial use. Because the magnetostrictive effect is an intrinsic material property that is robust against external factors such as stress and cyclic fatigue, magnetostrictive devices are suitable for harsh environments. This article provides an overview ofmagnetostrictivematerials and devices, particularly focused on Metglas, Terfenol‐D, and Galfenol. Various transducer topologies are presented and discussed, along with quantification of performance metrics and experimental aspects related to understanding and harnessing the intrinsic nonlinearities of magnetostrictive materials. Selected modeling approaches considering both constitutive material behavior and system response are presented.