| The sintering temperature of conventional lead-based piezoelectric ceramic is 1200℃to 1350℃. The microstructure and properties of ceramics are difficult to control because of the volatility of PbO during sintering at such high temperatures. In addition, the high firing temperatures require the use of expensive metals for internal electrodes in multilayer piezoelectric devices. The development of low-sintering-temperature piezoelectric ceramics will, therefore, reduce energy consumption and environmental pollution and enable the ceramics to be co-fired with less expensive metals in multilayer devices. Low temperature sintering of piezoelectric ceramics and tape-casting of piezoelectric ceramic tape are studied in this paper.The organic additives'mechanism, selective rules and their roles in preparing tape-casting ceramic slurry are discussed. The organic additives include dispersant, binder, plasticizer and solvent. Based on the characteristic of green powder, triolein is chosen as dispersant, polyvinyl butyral (PVB) is chosen as binder, polyethylene glycol(PEG)400 and PEG2000 are chosen as plasticizer, and butanone with ethanol are chosen as dual-combining solvent.The mechanism and the methods of low temperature sintering piezoelectric ceramics are investigated. After summarizing three methods for low temperature sintering piezoelectric ceramics, an optimal recipe as Pb (Zr0.53Ti0.47)O3- BiFeO3- Ba(Cu0.5W0.5)O3 (PZT-BF-BCW) is presented. To prove the property of the recipe, some specimens are made by traditional dried mould process using the optimal recipe mentioned above. And the experimental results show that, the optimal sintering temperature of the specimens is 1000℃.The experiments of preparing piezoelectric ceramic green tape using tape-casting technique have been done. And the influence of binder's and ceramic powder's different adding amounts on the property of ceramic slurry and the piezoelectric ceramic green tape is studied. Finally the best adding amount of the organic additives including dispersant, binder, plasticizer and solvent are determined.The organic burnout process and the sintering process of green tape prepared by tape-casting are discussed. The flat and high-density thick ceramic film with well-grown grains was obtained by sintering at the temperature of 1000℃. XRD patterns show that the samples have the structure of perovskite. This tape could be used for manufacturing low temperature co-firing ceramic (LTCC).
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