0-3型压电陶瓷/硫铝酸盐水泥复合材料的介电频率特性和铁电特性

以硫铝酸盐水泥为基体, 铌锂锆钛酸铅[ 0. 08Pb (Li_1/4 Nb_3/4 ) O₃ ·0. 47PbTiO₃ ·0. 45PbZrO₃ ] (简称PLN)压电陶瓷颗粒为功能体制备了0-3 型水泥基压电复合材料。利用X 射线衍射(XRD) 和扫描电子显微镜(SEM) 对水泥基压电复合材料的相组成和显微结构进行了分析和观察, 重点研究了水泥基压电复合材料的介电频率特性和铁电特性。结果表明, 压电陶瓷颗粒与硫铝酸盐水泥的水化产物结合良好; 随着PLN 含量的增加, 复合材料的介电常数ε_r 、剩余极化强度Pr和矫顽电场强度Ec均增大; 在40～100 kHz 频率范围内, 水泥基压电复合材料的介电常数ε_r均随频率的增大而迅速降低, 这主要受复合材料中的界面极化所影响, 高频时, 介电常数变化较小, 表现出良好的高频介电稳定性; 复合材料的电滞回线发生畸变的原因主要是PLN 压电陶瓷破碎成颗粒后, 本身存在许多缺陷, 且与水泥复合后存在许多界面气孔。 

Dielectric frequency and ferroelectric characteristics of 0-3piezoelectric ceramic/ sulphoaluminate cement composites

0-3 cement based piezoelect ric composites were fabricated using sulphoaluminate cement and piezoelect ricceramic [0.08Pb (Li1/4 Nb3/4 ) O3 ·0. 47PbTiO3 ·0. 45PbZrO3 ] as raw materials. The phase component s and micrO2st ructures of the composites were analyzed by XRD and SEM. The dielectric f requency characteristics and ferroelectriccharacteristics of the composites were mainly investigated. The results indicate that the bonding between piezoelectricceramic particle and hydration product s of sulphoaluminate cement is good. With increasing the PLN content , thedielect ric constantεr , remanent polarization Pr and coercive field Ec increase. The dielectric constant decreases sharplywith f requency increasing over the f requency ranges f rom 40 kHz to 100 kHz , which is att ributed to interfacialpolarization in the composite. At high f requency , the dielect ric constant changes slightly , which means that thecement-based piezoelect ric composites have good high f requency stability. The reasons why the hysteresis loopsdistort are mainly that there are both many defect s in the piezoelect ric ceramic particles af ter breaking and manyinterfacial pores in the composites.