9.掺杂MgO对Ba0.8Sr0.2TiO3陶瓷介电性的调制

                                                                    左小艳，余萍*

材料科学与工程学院，四川大学，成都，610064

关键词：钛酸锶钡陶瓷；溶胶凝胶；MgO掺杂；介电常数；介电特性

中图分类号：TB332               文献标识码：A

摘要：采用溶胶凝胶法制备了Ba_0.8Sr_0.2TiO₃陶瓷粉末，通过固相掺杂的方式，利用传统陶瓷制备工艺制备了MgO掺杂的Ba_0.8Sr_0.2TiO₃陶瓷，研究了MgO的掺杂量对Ba_0.8Sr_0.2TiO₃陶瓷结构及晶粒尺寸的影响，研究了MgO的掺杂量对Ba_0.8Sr_0.2TiO₃陶瓷的介电性、铁电性的影响。在此基础上讨论了MgO掺杂Ba_0.8Sr_0.2TiO₃陶瓷结构与电学性能的内在相关性。研究结果表明，MgO的掺杂量可显著影响Ba_0.8Sr_0.2TiO₃陶瓷的居里温度，以及介电常数随温度的变化特性，随着MgO掺杂量的增加，介电常数随温度的非线性变化范围逐渐减小，并且陶瓷的击穿强度会增加，介电损耗会减少。说明适当的MgO掺杂可改善Ba_0.8Sr_0.2TiO₃陶瓷的介电性，调制Ba_0.8Sr_0.2TiO₃陶瓷的介电性的非线性。

MgO dopingmodulation on dielectric properties of Ba_0.8Sr_0.2TiO₃ceramics

ZUO Xiao-yan   YU Ping

Collegeof Materials Science and Engineering, Sichuan University, Chengdu, 610064

Keyword:Barium strontium titannate ceramics; sol-gel method; doped-MgO; permittivity;dielectriccharacteristics

Abstract:Ba_0.8Sr_0.2TiO₃ceramicpowderswas prepared by sol-gel method.MgO-doped Ba_0.8Sr_0.2TiO₃ceramics were prepared by solid-statedoping method.The effects of MgO doping contenton the microstructure and electric properties，especially on dielectric andferroelectric properties were investigated experimentally. The correlation of structureand electrical properties of Ba_0.8Sr_0.2TiO₃-xwt%MgOceramics was discussed. The results show that MgO doping contents significantlyaffect the Curie temperature and the dielectric response characteristics. MgOis beneficial to increase the breakdown strength and improve the temperaturestability of dielectric properties of Ba_0.8Sr_0.2TiO₃ceramics. It demonstrates that appropriate MgO doping can improve Ba_0.8S_r0.2TiO₃ceramics dielectric, modulating the dielectric nonlinearity of Ba_0.8Sr_0.2TiO₃ceramics.