摘要
目的研究过量PbO对0.25Pb(Mg1/2W1/2)O3-0.41Pb(N i1/3Nb2/3)O3-0.34PbTiO3+5%WO3+0.25%MnO2+xPbO陶瓷(简写为PMW-PNN-PT基陶瓷,x=0,0.04,0.06,0.08)的相组成、微观结构和介电性能的影响规律。方法用半化学法制备了PMW-PNN-PT基陶瓷,通过对预烧粉体和陶瓷的XRD分析确定其相组成,用扫描电镜观察陶瓷的微观形貌,用LCR测试仪测试陶瓷的介电性能。结果随PbO含量的增加,预烧粉体中立方焦绿石相Pb3Nb4O13(简写为P3N2)逐渐减少,三方焦绿石相Pb2Nb2O7(简写为P2N)逐渐增多;过量PbO可以增加陶瓷中的钙钛矿相含量,减少P3N2和Pb2WO5的含量,使陶瓷的晶界逐渐清晰,晶粒发育良好,陶瓷的介电常数逐渐增大,但介电温度稳定性逐渐变差。结论采用半化学法制得了高介电温度稳定性的未过量PbO的PM-PNN-PT基陶瓷,其介电常数高于日本TDK公司的同类产品。
Aim To study the effect of excess PbO on the phase constitutes, microstructure and dielectric properties of 0.25Pb（ Mg1/2W1/2 ）O3-0.41Pb（ Ni1/3 Nb2/3 ）3-0. 34PbTiO3＋5% WO3＋0.25% MnO2＋xPbO ceramics （abbreviated PMW-PNN-PT based ceramics） with x=0,0.04,0.06 and 0.08. Methods A series of PMW-PNN-PT based powders and ceramics were prepared by semichemical method. The phase constitutes and the microstructures of the powders and ceramics were characterized by XRD and SEM methods, and the dielectric temperature stability of the ceramics were investigated through the measurement of the temperature dependence of the dielectric constant. Results With the increment of excess PbO content, the cubic pyrochlore phase Pb3Nb4O13 decreased and the rhombohedral pyrochlore phase Pb2Nb2O7 increased gradually in the powders; The excess of PbO can increase the content of pervoskite phase and reduce the content of pyrochlore phase Pb3Nb4O13 and Pb2WO5 in the ceramics, and the ceramics had clear crystal boundary and excellent density. And with the increment of excess PbO, the dielectric constant increased drastically, but the dielectric temperature stability of the ceramics become worse. Conclusion The un-excess PbO PMW-PNN-PT based ceramics with high dielectric temperature stability prepared by semichemical method, and the dielectric constant was superior to that of the sample of TDK corporation.
出处
《西北大学学报（自然科学版）》
CAS
CSCD
北大核心
2005年第4期409-412,共4页
Journal of Northwest University（Natural Science Edition）
基金
陕西省自然科学基金资助项目(2001H06)
陕西省高校省级重点实验室重点科研基金资助项目(02JS12)
关键词
钨镁酸铅
介电常数
过量氧化铅
半化学法
lead magnesium tungstate
dielectric constant
excess PbO
semichemical method
