title: The resonance frequencies on mechanically pre-stressed ultrasonic piezotransducers.
abstract: 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.
authors.affiliation: Superior Center of Technology Education, Campinas State University, Limeira, SP, Brazil. arnold@claretianas.com.br
authors.forename: F J
authors.initials: FJ
authors.lastname: Arnold
authors.forename: S S
authors.initials: SS
authors.lastname: Mühlen
mesh_terms: D000162:Acoustics; D002516:Ceramics; D019544:Equipment Failure Analysis; D006801:Humans; D008670:Metals; D013314:Stress, Mechanical; D014159:Transducers; D014463:Ultrasonography / Q000295:instrumentation*
chemical_list: D008670:Metals