Study On The Structure And Performance Of PMZN Piezoelectric Materials

PMZN piezoelectric ceramic is a kind of modified PZT materials with the incorporation of PMS materials and PZN materials. PMS materials have many good properties such as high Kp and Qm, the good time and temperature stability of resonance frequency, and low dielectric loss at high frequency. PZN materials have excellent piezoelectric and dielectric performances near MPB. Therefore, the piezoelectric ceramic with desired structure and properties can be obtained by introducing PMS materials and PZN materials into PZT materials, which has great potential of being widely applied in many fields, especially in advanced sound-electricity transducer.The research is conducted with the aim at producing PMZN piezoelectric ceramic with the desired piezoelectric properties by using moderate resource material ratio and preparation technique. The electrical properties and microstructure of the materials have been investigated, the effects of composition and technical parameters on electrical performance and their mechanisms have been analyzed. On the base of above researches, the optimized composition and fabrication conditions have been ascertained, and PMZN piezoelectric ceramics with excellent electrical performance have been produced.PZT powders were synthesized by solid-state reaction method, sol-gel method and sol-self-combustion method respectively, and PMZN piezoelectric ceramics with the synthesized PZT as matrix respectively were fabricated. The microstructure features of the PMZN ceramics were investigated by XRD, SEM and IR, and the electrical properties were measured and investigated. The results of above researches show that the PMZN piezoelectric ceramics have fine piezoelectric and dielectric properties. The sintering temperatures of the PMZN ceramics, with the sol-gel method synthesized PZT and thesol-self-combustion method synthesized PZT as matrix respectively, are much lower than that of the PMZN ceramics with the solid-state method synthesized PZT as matrix. Dense microstructure was detected in the PMZN piezoelectric ceramics with the sol-gel method synthesized PZT and the sol-self-combustion method synthesized PZT as matrix respectively, exhibiting homogeneous grain sizes less than 1 u m. The improvement of piezoelectric properties was obtained, and the frequency constant of the ceramics was changed obviously.