PLZT压电陶瓷准同晶相界处显微组织与性能的研究

Study on microstructures and properties of PLZT piezoelectric ceramics at MPB

采用粉末冶金法制备了压电陶瓷材料Pb0.92La0.08(ZrxTi1-x)O3(简称PLZT),研究了Zr与Ti的原子比对材料物相组成、显微结构以及介电、压电性能的影响。XRD和SEM分析结果表明,当0.64≤x≤0.66时,材料近于准同晶相界;x=0.65时,所得密度最高,达到7.62g/cm3,相对密度为96.33%,介电、压电常数和机电耦合系数最大,分别为εr=1182,d33=136.8pc/N,Kp=0.284,具有优良的综合电学性能。其原因主要是该陶瓷在电场作用下易发生准同晶相变。

Piezoelectric ceramics with the compositions of Pb0.92La0.08（ZrxTi1-x）O3（PLZT）ceramics were successfully prepared by powder metallegy method.The effects of Zr/Ti ratio,x,in the vicinity of the morphotropic phase boundary（MPB）on the phase structure 、microstructure and electrical and piezoelectrical properties of PLZT ceramics have been investigated.The density of sample was measured by Archimedes,the phase structure and microstructure were analysed by XRD and SEM.The results indicate that the ceramics are similar to that at MPB while 0.66 ≤ x≤0.64,and if x is at 0.65,they have excellent properties such as：εr = 1182,d33 = 136.8pc/N.The main cause for the improved properties is due to easy occurrence of MPB in the ceramics.