Piezoelectrics are the active material of choice in a wide range of electromechanical applications including SONAR, medical ultrasound and non-destructive evaluation. However, designers of high power piezoelectric systems have suggested that a discrepancy exists between mathematical modelling predictions and measured transducer performance. In most high power applications piezoelectric materials are operated under large compressive stresses. Manufacturers of piezoelectric materials publish a wide range of performance data, however, the majority of the data is acquired under no bias stress. In this paper, a new technique that facilitates the characterisation of piezoelectric materials over a wide range of operating stresses (0-140MPa) at their resonant frequency is described. It builds upon the IEEE techniques for piezoelectric characterisation and utilises measurement equipment found in the majority of piezoelectric development laboratories. The technique therefore offers a low cost extension to existing facilities for the accurate determination of piezoelectric properties under high stress loading. Results gained using the new technique confirm that substantial variation in electromechanical properties of piezoelectric materials occurs under stress loading. Using this derived data, a more informed evaluation of transducer materials and more accurate predictions of transducer performance can be made.

Date Published: 23 April 2008
PDF: 8 pages
Proc. SPIE 6929, Behavior and Mechanics of Multifunctional and Composite Materials 2008, 692929 (23 April 2008); doi: 10.1117/12.776331

Published in SPIE Proceedings Vol. 6929:
Behavior and Mechanics of Multifunctional and Composite Materials 2008
Marcelo J. Dapino; Zoubeida Ounaies, Editor(s)