Study of vibrational characteristics for piezoelectric sandwich ultrasonic transducers

Abstract Electro-acoustic efficiency is an important parameter for high power ultrasonic transducers. When a transducer is acoustically matched into its load, the electro-acoustic efficiency reaches the potential efficiency, which depends only on the transducer's unloaded parameters, not on the acoustic load. The relation between the potential efficiency and the contacting loss caused by bonding at interfaces and the relation between the potential efficiency and the dimensions of the end sections of the sandwich transducer are examined. The effects of the loss at the contacting surfaces on the transducer's resonant frequency and the potential efficiency are studied. The results show that there is an optimum design of the sandwich transducer which maximizes the potential efficiency and minimizes the effect of the contacting loss on the transducer's resonant frequency.