| PZT piezoelectric thick film with eminent properties, either has the merits of the block material or that of thin film. PMS-PNN-PZT piezoelectric thick film ceramic material was prepared on Al2O3 substrate by screen printing method .Effects of sintering temperature,soaking time and sintering atmosphere on piezoelectric and dielectric properties and microstructure of piezoelectric thick film was studied. Phases, thick film orientation and microstructure were analysed by XRD and SEM, The results show that piezoelectric thick film ceramic material with excellent performance was maded at sintering temperature of 1060℃for 80 min in PbO atmosphere. Thereinto, piezoelectric constant d33 is 160 pC/N, comparative dielectric constantεr is 1112, mechanical quality factor Qm is 1250, electromechanical coupling coefficient Kp is 0.52.Effects of the compositions to performances of the PMS-PNN-PZT piezoelectric thick film were studied, The results shown that ,Qm of the sample was increased along with the content of the PMS ,ε33/ε0 of the sample was increased remarkably by adding a few PNN component. Effects of the polarized conditions (polarized field intensity, polarized temperature, polarized time) to performances of the PMS-PNN-PZT piezoelectric thick film were discussed, the piezoelectric thick films with excellent performances were obtained at the condition of polarized field intensity is 4 kv/mm, the polarized temperature is 120℃, the polarized time is 25 min.Choosing Ce, Mn, Sr as the doped element, Effects of different doped proportions to performances of the PMS-PNN-PZT piezoelectric thick film were studied. d33 andεr of samples were enhanced by adulterating the right amount of Ce ; Qm was enhanced by adulterating the right amount of Mn; d33, Kp and Qm were enhanced by adulterating a few of Sr.The high temperature diffusion among the substrate, below electrode and the PMS-PNN-PZT film was studied; Effects of SiO2 buffer on piezoelectric and dielectric properties and microstructure of PMS-PNN-PZT piezoelectric thick film was studied. Phases, thick film orientation and microstructure were analysed by XRD and SEM, the results show that the diffusion among three layers was effectively prevented by the buffer, d33 andεr of sample are improved, the piezoelectric constant d33 is 190 pC/N, comparative dielectric constantεr is 1210, mechanical quality factor Qm is 1330, electromechanical coupling coefficient Kp is 0.54.The experiments indicated that, the dispersivity and the uniformity were improved by using dispersant agent of thick film slurry which was used for screen printing. The conglobation phenomenon of Slurry was decreased by supersonic dispersing for a right of time, thus the dispersivity and the uniformity of thick film slurry were improved. The blowholes were decreased by increasing the number of the screen-printing , thus performances of the sample were enhanced.The density of the sample was improved by a isopress-treatment, thus the piezoelectric constant of the sample was enhanced.
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