Multicomponent ceramic materials on the basis of PZT for the production of piezoelectric resonators

Investigations on the influence of the PbTiO3 content on
the crystalline and domain structure of PZT-based four-component solid solutions
have been performed. It has been shown that there is a close relation between
the structure and temperature stability of the resonance frequency (fr) of the
fabricated piezoceramic transducers. Better and more stable results have been
obtained by doping and modifying the basic chemical composition obtaining
Pb(Zr1-xTix)O3. The compositions with minimal [ampersand]Delta;fr/fr, within the
temperature range T=213-358K (in relation to room temperature Tr=293K),
exhibited (i) the smallest internal friction (Qm-1), (ii) the highest mechanical
quality (Qm), (iii) high values of spontaneous deformation of the elementary
cell ([ampersand]delta;T and [ampersand]delta;Re), (iv) the complex a-c-domain structure in the
tetragonal phase (T) and the simple domain structure in the rhombohedral phase
(Re). The practical result of the present work was the fabrication of
piezoceramic electric band filters exhibiting [ampersand]Delta;fr/fr[ampersand]lt; 0.2[ampersand]percent; and
a high mechanical quality factor (Qm=3225).