Production of piezoceramic powders by the thermal two-stage process

The present paper describes the production of lead zirconate titanate (PZT) with different additives and of lead metaniobate (PN) by means of the Thermal Two-Stage Process. This process, especially developed for the synthesis of multicomponent ceramic powders is characterized by the following: the starting constituents are liquid metalorganic precursors, such as alcoholates or acetates, which are converted to a homogeneous, multicomponent ceramic powder by spray drying the liquid precursors, resulting in an organic granulate, which is then followed by the thermal conversion of this organic powder into the final ceramic material. The resulting ceramic powder shows favourable properties with respect to homogeneity and further processing, e.g. pressing and sintering of compacts. The efficiency of the process will be demonstrated by the characterization of the piezoelectric properties of the sintered compacts. (C) 1999 Kluwer Academic Publishers.