Design and Output Characteristics of Ultrasonic Transducer Based on Rare-Earth Giant Magnetostrictive Material

A new type of rare-earth giant magnetostrictive transducer, working in ultrasonic frequencies, is designed by the structural dynamic model and the dynamic coupling model. Based on the vibration, wave, and frequency equations, the structural dynamic model of the transducer is established. Using COMSOL Multiphysics software parametric design method, considering the influence of materials, shapes, and dimensions on the output characteristics of the transducer, the optimum mechanical structure of the ultrasonic transducer is determined. The magnetic circuit structure is analyzed by the dynamic coupling model based on the Jiles–Atherton model, Maxwell’s equations, and magneto-mechanical coupling effect. The prototype of the ultrasonic transducer is fabricated. The relationship between the output characteristics and the frequency is studied. The results demonstrate that the ultrasonic transducer can work in the range of 18–22 kHz and exhibits higher magneto-mechanical conversion efficiency at the frequency of 19.5 kHz.