Improvement of Temperature Dependence of Piezoelectric Elements

Abstract

The relationships between the equivalent circuit constants of a piezoelectric element and the piezoelectric d33- and g33-constants were first clarified. The temperature dependence of the composed equivalent circuit constants was then decreased by connecting the piezoelectric element to a temperature-compensating capacitor, either in series or in parallel. Furthermore, new sandwich-like piezoelectric elements consisting of stacked piezoelectric ceramic and dielectric ceramic layers were constructed to decrease the dependence on temperature. The piezoelectric d33-constant of Pb(Zr, Ti)O3 changed by about 15% over the temperature range of 0 to 160° C. The new sandwich-like element, however, exhibited a change of less than 3% over the same temperature range.