Properties of nanocrystalline ferroelectric PZT ceramics

Amorphous nanopowders of Pb(Zr 0.5Ti 0.5)O 3 (PZT) solid solution were obtained by sol-gel processing. As-obtained nanopowders ( r ̄ ≈30×10 −9 m) underwent consolidation by conventional ceramic sintering, hot pressing, and rapid thermal annealing. As result of such technological methods PZT ferroelectric ceramic samples were obtained. They exhibited lack of voids, density close to the theoretical X-ray density, homogeneity from both chemical and physical point of view and stoichiometric chemical composition. It was found that each ceramic sample was a conglomerate of grains exhibiting mean dimension r ̄ =0.3–3×10 −6 m depending on sintering conditions. The nanocrystalline structure of the ceramics grains has been revealed. Dimension of the crystallites ( D ̄ =20–75×10 −9 m) were found to depend on temperature ( T S) and the rate of sintering ( ν T) of the amorphous nanopowders. Dielectric and piezoelectric properties of nanocrystalline PZT ceramics depended on both sol–gel processing conditions and sintering conditions.