An ultrasonic vibrator constructed from laminated Galfenol steel.

An ultrasonic vibrator has been developed to serve as the drive mechanism for an electroacoustic transducer. This design explores the unique characteristics of Galfenol, a recently invented giant magnetostrictive material. In addition to possessing competitive strain capabilities, strong mechanical properties, and a high‐magnetic permeability, Galfenol does not require a prestress mechanism and can be laminated to effectively mitigate eddy current losses. Designing the vibrator required the authors to carefully engineer the magnetic circuit so that proper bias fields could be established using a permanent magnet. This step will be demonstrated with one‐ and two‐dimensional models. Drive coil considerations will also be discussed and the fabrication and assembly of the vibrator will be shown along with in‐air measurements.