| PZT ceramics of the excellent piezoelectric properties was prepared since 1954. It has been the main transducer material on the band of the megahertz frequency, including sonar transducer and a variety of ultrasound transducers. In fact, its requirements are different in different occation. Now a variety of piezoelectric ceramic formulations are designed to adapt to different requirements and design.In this paper, PMS-PZT piezoelectric ceramics of using on the ultrasonic transducer were prepared by conventional solid phase. The thesis studied the ceramic dielectric and piezoelectric properties of the different sintering techniques, different Sr, Ba complex doping and CeO2 doping. The structure, morphology, composition, electrical properties of ceramic samples were analyzed by XRD, SEM, EDS, impedance analyzer, d33 quasi-static test instrument.The grains of Pb(Sb2/3Mn1/3)0.05ZrO.47Ti0.48O3(PMS-PZT) piezoelectric ceramics grown up with increasing of sintering temperature, which improved the quality of crystallization. When ceramic samples were sintered at 1200℃, d33 and Kp declined quickly which be due to fluctuations in chemical composition. The change in density can not be directly used to explain the variation of dielectric properties. Because PMS-PZT ceramics system would form low temperature eutectic content at 1100℃ which resulted in decreasing of dielectric constant and inceasing of dielectric loss. Providing PbO and O2 atmosphere during the sintering process were in favor of suppressing volatilization of PbO and accelerating Zr4+ diffusion, which promoted ceramics densification. For transient liquid phase sintering, the heating rate increase would help improve the amount of liquid phase, which promoted the sintering. But, the rapid heating rates can also cause abnormal grain growth, thereby reducing the ceramic properties.After studying the sintering process, the compound doping of Pb0.92Sr0.08-xBax(Sb2/3Mn1/3)0.05Zr0.48Ti0.47O3(PSBSM-PZT) piezoelectric ceramics were studied. The componet of Sr(or Ba) doped ceramic located tetragonal phase region, and Sr/Ba co-doped ceramic located in Morphotropic Phase Boundary (MPB) which rhombohedral and tetragonal phases coexist. Since the piezoelectric ceramics in MPB can get a high dielectric and piezoelectric activity, the Sr/Ba co-doped piezoelectric ceramics exhibit a high piezoelectric properties. But since the electric domain deflection increased internal friction and loss on structure, than the the mechanical loss and dielectric loss material of ceramic increased.Sr/Ba co-doped can improve electromechanical coupling factor, while decreased mechanical quality factor Qm and increased dielectric loss. So Pb0.92Sr0.06Ba0.02(Sb2/3Mn1/3)0.05Zr0.48Ti0.47O3(P6SBSM-PZT) ceramic should be further modificated with amphoteric doping CeO2. CeO2 doped ceramic could increase the of content tripartite phase, but the excessive CeO2 doped can cause pyrochlore phase and miscellaneous generated. In addition, grain refinement can be achieved with CeO2 doped. But excess can cause CeO2 enrichment at the grain boundaries, resulting in grain boundary strength reducing, which the ceramic fracture mode were transited from transgranular to intergranular fracture fracture. As a conventional CeO2 amphoteric additives of piezoelectric ceramic, the piezoelectric ceramic doped by a small amount of CeO2 can obtain a higher Kp and Qm. In 1250℃ sintering,0.25 ω% CeO2 doped cerammic got optimum performance:d33=323C·N-1, Kp=0.60,Qm=1396,εr=1309, tanδ=4.74%.
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