Compositional fluctuations and properties of fine-grained acceptor-doped PZT ceramics

Fine-grained acceptor-doped lead zirconate titanate (PZT) ceramics were sintered in a wide range of temperatures and times. The differences in dielectric and piezoelectric properties were relevant and quite independent of grain size. The incorporation of acceptor dopant into the solid solution of PZT was responsible for the change of properties, the evolution Of secondary phases and the weight loss behaviour. The PbO rich phase located between grains displaced from the PbO-PZT system to PbO-PZ system when il on cations entered the PZT lattice. At this time, precipitated monoclinic grains of zirconia among with tetragonal perovskite grains revealed the compositional fluctuations. After the iron cations entered into solid solution the liquid formed dissolved new PZT grains again and displaced to PbO-PZT system with increasing of weight loss. Decomposition experiments revealed also the nature and the evolution of the second phases that are in accordance with TEM observations. (C) 1998 Elsevier Science Limited.. All rights reserved.