Low-frequency ultrasonic piezoceramic sandwich transducer

This paper presents an ultrasonic piezoceramic sandwich transducer (UPST), utilised for ultrasonic field generation in water and cavitational effect achievement. This device will be used to produce enlargement of the bubbles, initiated by the incident shock wave on the calculus in the lithotripsy process. The piezoceramic sandwich transducer powered by a function/pulse generator type IWATSU SG-4511 converts the electrical signal in mechanical vibrations, which are propagated in water. A PZT disc sensor converts the underwater waves in electrical signals, displayed by LeCroy 9310 AM oscilloscope. The purpose was to realise an ultrasonic piezoceramic sandwich transducer with low resonance frequency, tuneable energy and broad bandwidth. The UPST transducer, integrated to an ESWL electromagnetic lithotripter, yields enhancement of the cavitation effects, utilised in the comminution of kidney stones.