D. Damjanovic et al., INSTABILITIES IN THE PIEZOELECTRIC PROPERTIES OF FERROELECTRIC CERAMICS, Sensors and actuators. A, Physical, 53(1-3), 1996, pp. 353-360
The large piezoelectric effect of ferroelectric ceramics is utilized i
n many devices for sensing and actuating purposes. In this paper, the
longitudinal direct piezoelectric effect in ceramics based on lead zir
conate titanate, lead titanate, barium titanate and bismuth titanate i
s investigated as a function of the amplitude and frequency of the ext
ernal pressure, the crystal structure and microstructure of the cerami
cs. The domain-wall contribution to the piezoelectric response appears
to be a dominant extrinsic origin of instabilities in the observed pi
ezoelectric effect but, for a given composition, it can be affected by
dopants and microstructure. Other sources of instabilities in the pie
zoelectric response, such as chemical inhomogeneities and defects, are
also discussed. It is shown that, with proper modifications, it is po
ssible to freeze out completely the extrinsic part of the piezoelectri
c response in some of the examined compositions and to obtain a stable
behaviour, independent of the frequency and magnitude of the external
driving held.