Sonderforschungsbereich 595

Influence of PbO stoichiometry on series production of PZT and multilayer actuators

Prof. Dr. Michael J. Hoffmann, Institut für Keramik im Maschinenbau (IKM),
Robert Bosch GmbH, Bamberg

The aim of project T2 are investigations on the influence of lead-oxide stoichiometry and grain size on properties of lead zirconate titanate (PZT) ceramics and multilayer actuators. The project will be performed in collaboration with the Robert Bosch GmbH in Bamberg. The transfer project T2 is based on results and methods that have been elaborated by project A2 during the first two funding periods of the SFB 595. PbO content and grain size are related to electromechanical performance and most probably also to failure behaviour. Moreover, they are important material properties for control of industrial processing procedures and quality standards in the mass production of multilayer actuators. One approach to these issues will be to synthesize PZT compositions with different PbO contents, to fabricate and characterize the ceramics and to evaluate the results with respect to the resulting PbO stoichiometries. Additionally we will modify under laboratory conditions multilayer actuators, designed corresponding to serial production devices, by variation of the PbO content in the sintering atmosphere. Conformable experiments with multilayer actuators and ceramics will be performed in order to check whether the results found for ceramics are applicable also to characterize the behaviour of actuator devices. Furthermore we will evaluate the applicability of low temperature firing PZT powders based on Zr/Ti Hydrates for the production of multilayer actuators. In order to improve the strain characteristics of these materials, an important line of development is to find suitable methods to enhance grain growth.