| (1-x)Pb(1-y-z)PrySrz(Zr1/2Ti1/2)O3-xPb(Ni1/3Nb2/3)O3(short forPZT-PNN) piezoelectric ceramics was selected as research object. The samples were gained by solution treatment, adding Pr6O11 and SrCO3 and improving the preparation technics. The sintering temperature was decreased from 1250℃to 1150℃), the volume density and volume resistivity were increased from 7.60 g/cm3 to 7.80 g/cm3 and from 0.8×1012Ω·cm to 1.2×1012Ω·cm, respectively.So the system of PNN-PZT could be used in piezoelectrice component which is monolithic structure.The X-ray diffraction (XRD) indicated: when calcinating at 960℃/2h, Zr/Ti=0.5/0.5, the content of PNN x=0.3, the system is in the morphotropic phase boundary(MPB),and has both the tetragonal and trigonal phase. But when Zr/Ti=0.5/0.5, x=0.2, the compositions shifts away from the trigonal phase across the MPB toward the tetragonal phase and reduces the Curie temperature. By the photos of scanning electronic microscope (SEM),it is found that when sintering at 1150℃/2h, the content of Pr6O11 and SrCO3 were 0.02mol% and 0.03mol%, the crystal grain grew well, stacked compactly, had homogeneous grain size(about 3～5μm).So the optimal formulation is 0.8Pb0.95Pr0.02Sr0.03(Zr1/2Ti1/2)O3-0.2Pb(Ni1/3Nb2/3)O3.The influence of technical parameters on properties of piezoelectric ceramics (1-x)Pb(1-y-z)PrySrz(Zr1/2Ti1/2)O3-xPb(Ni1/3Nb2/3)O3 were also discussed. The influence of sintering temperature on the properties of this system is more than sintering time, and optimum properties can be obtained with broad sintering temperature 1150℃～1190℃and sintering time 2 hours respectively. The optimum polarizing electric field, polarizing temperature and polarizing time is as follows: 3kV/mm, 100℃, 30min.When optimum the formulation composition and preparation technology were selected, the optimum tesults were obtained: d33=530pC/N, g=7.87g/cm3, tanδ=1.8%,ε33T /ε0=3000,Ïv=1.2×1012Ω·cm, Kp=57.4%, less aging rate of d33,ε33T /ε0and tanδ(within 10%), Tc=200℃.
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