中文摘要：

用固相反应法制备了Ba1-xSrxTiO3（BST）及Ba0.6-xPbxSr0.4TiO3（BPST）陶瓷,通过XRD,FESEM和拉曼谱分析了Pb掺杂对Ba0.6Sr0.4TiO3样品的晶格、相变及表面形貌的影响.测试了BST及BPST样本系列的介电常数-温度（介温）谱,研究了BST及BPST钙钛矿结构中Sr和Pb成分对居里温度和居里峰值的调节机理,运用修正的Smolenski成分起伏理论和居里外斯定律,对BPST弥散相变进行了数学统计分析,得出弥散指数α为1.29—1.73,相变宽度为13.2—22.3℃,居里常量为1.25×105—2.87×105K数量级.

英文摘要：

Ba1-x SrxTiO3 （BST） and Ba0.6-x PbxSr0.4 TiO3 （BPST） ceramics were prepared by conventional solid-state reaction method. The analysis of XRD,FESEM and Raman spectroscopy showed the effects of Pb-doping on the crystal lattice, phase transition and surface morphology of Ba0.6 Sr0.4 TiO3,respectively. And the temperature dependence of permittivity （ε-T properties）for all ceramics were measured at a frequency of 10 kHz. The mechanism that Curie temperature and the peak value of permittivity are modulated by Sr and Pb content in BST and BPST perovskite has been revealed. In addition, all samples exhibit a diffused phase transition （DPT）,especially for the ceramic Ba0.5Pb0.4Sr0.1TiO3,which can improve its temperature stability of tunability as phase shifter than others. Some ferroelectric parameters are calculated to interpret the DPT by adopting Smolenski’s theory and Curie-Wise law. For example,the values of diffuseness exponent α,Curie constant and transition region have changed from 1. 29 to 1. 73,from 1. 25 × 105 to 2. 87 × 105 K,and from 13. 2 ℃ to 22. 3 ℃ ,respectively.