The resonance frequencies on mechanically pre-stressed ultrasonic piezotransducers.
The piezotransducers employed in high power ultrasound are composed of piezoelectric ceramics and metallic pieces. These transducers are mechanically pre-stressed in order to avoid the ceramic fractures when high voltage is applied under resonance. The resonance and anti-resonance frequencies are shifted depending on the level of applied mechanical pre-stressing. This paper discusses some causes of this shifting on a experimental study. The discussion takes into account the variations on characteristic parameters of the ceramics and the acoustic coupling between parts of the transducer.
Arnold
F J
FJ
Superior Center of Technology Education, Campinas State University, Limeira, SP, Brazil. arnold@claretianas.com.br
Mühlen
S S
SS
D000162:Acoustics; D002516:Ceramics; D019544:Equipment Failure Analysis; D006801:Humans; D008670:Metals; D013314:Stress, Mechanical; D014159:Transducers; D014463:Ultrasonography / Q000295:instrumentation*
D008670:Metals