Bi_2O_3/Li_2O助熔剂BST介电陶瓷的低温烧结研究  

The Investigation of Low Temperature Sintering of BST Dielectric Ceramics with the Bi_2O_3/Li_2O Flux

作　　者：曹静[1] 龙禹[1] 冷森林 石维[1] 

机构地区：[1]铜仁学院物理与电子工程学院,铜仁554300

出　　处：《中国陶瓷》2015年第8期16-18,共3页China Ceramics

基　　金：贵州省大学生创新创业训练计划项目[201310665001和201310665002];贵州省重点实验项目[黔财教2011(232)]

摘　　要：采用固相反应制备了低温烧结(Ba0.71Sr0.29)TiO3-x Bi2O3/Li2O(x=0.02、x=0.03、x=0.05)陶瓷,差热分析结果表明助熔剂Bi2O3/Li2O可降低(Ba0.71Sr0.29)TiO3陶瓷的烧结温度至820℃并获得相对密度为97%的BST陶瓷。X射线衍射发现制备过程有少量次生相生成,分别为Li2TiO3和Ba2TiO4。实验结果表明Bi2O3/Li2O助熔剂降低了(Ba0.71Sr0.29)TiO3的铁电性,这也是导致介电常数和介电损耗降低的原因。低温烧结机理涉及碳酸钡的中间体的形成,Li离子的熔融态迁移至BST结构中提供了促进反应进行的液相。An addition of just BizO3/Li20 to （Ba0.vlSro.29）TiO3-xBi2OjLi20（x=0.02, x=0.03, x=0.05）powder was ableto reduce the sintering temperature to 〈820 ℃ and produce ceramics with a relative density of 97%. Small amountsof two secondary phases were formed during this process： Li：TiQ and Ba2TiQ. The addition of Bi203/LizO depressesthe ferroelectric character of the （Ba0.7Sro.29）TiO3 and, as a result, reduces the permittivity, improves the temperaturecoefficient of permittivity, and reduces the dielectric losses. A low temperature sintering mechanism was proposed. Themechanism involves the intermediate formation of BaCO3, its melting and the incorporation of Li into the BST. Thesintering mechanism can be characterized as reactive liquid-phase sintering.

关 键 词：多层陶瓷电容器 (Ba Sr)TiO3 介电性能 低温共烧 

分 类 号：TQ174[化学工程—陶瓷工业]