Research progress on the nonlinearities of sandwich piezoelectric ceramic ultrasonic transducer

So far the sandwich piezoelectric ceramic ultrasonic transducer is the most widely used transducer in high-power ultrasonic equipment, which, however, will exhibit significant nonlinear characteristics under the high-power state. The research progress on the nonlinearities of sandwich piezoelectric ceramic ultrasonic transducer is reviewed. Some important theoretical results and experimental ones about the nonlinearities of piezoelectric ceramic are firstly summarized, and the research works about hard piezoelectric ceramic, which is commonly used in high-power ultra-sound field, are emphatically introduced. Secondly, the nonlinearities caused by the structure and production process of the sandwich piezoelectric ceramic ultrasonic transducer are briefly analyzed and discussed. The current research status on the nonlinear model of sandwich piezoelectric ceramic transducer is finally introduced.