27 Hysteresis Losses and Thermal Analysis of Giant Magnetostrictive High Power Ultrasonic Transducer

Giant magnetostrictive high power transducers usually work under a high intensity and frequency magnetic field. Hysteresis losses and eddy current losses are very heavy. At the same time, giant magnetostrictive materials (GGM) is sensitive to temperature. Therefore heat generation and temperature distribution is very important for the transducer's design. In this paper a high power ultrasonic transducer was designed. The magnetization behavior of GGM in the transducer was characterized by the modified Jiles-Atherton hysteresis model which considers eddy current losses and anomalous losses. Model parameters were determined from the least square fit between experimental values and model values. Various losses were calculated. Temperature distribution of the transducer was calculated with finite element method. Calculation results and experimental results show a good agreement.