粉体合成温度对钽酸锶铋陶瓷介电行为的影响(英文)  

EFFECT OF POWDER SYNTHESIS TEMPERATURES ON DIELECTRIC PROPERTIES OF SrBi_2Ta_2O_9 CERAMIC

作　　者：李宝让[1] 刘东雨[1] 毛雪平[1] 

机构地区：[1]华北电力大学,电站设备状态监测与控制教育部重点实验室,北京102206

出　　处：《硅酸盐学报》2008年第12期1705-1709,共5页Journal of The Chinese Ceramic Society

摘　　要：利用五氧化二钽(Ta2O5),碳酸锶(SrCO3)和三氧化二铋(Bi2O3)等原料,采用传统的粉体固相合成方法,在不同温度800,900,1 000℃和1 100℃合成钽酸锶铋粉体,研究粉体合成温度对钽酸锶铋陶瓷介电性能的影响。X射线衍射结果表明:不同温度下煅烧均能够合成钽酸锶铋单一物相,但是烧结致密程度明显不同,当粉体合成温度较低时,气孔相对细小,尺寸均匀。进一步的介电性能测试表明:粉体合成温度对Curie点和介电强度具有影响。较低粉体合成温度可以在一定程度上改善陶瓷的介电性能;较高的粉体合成温度则导致Curie点偏移,恶化陶瓷的介电性能;介电性能的改变主要和烧结过程中形成气孔缺陷有关。Raw materials Ta2O5, SrCO3 and Bi2O3 were used as starting materials to prepare SrBi2Za2O9 powders via the conventional solid-state reaction method. SrBi2Ta2O9 powders were prepared successfully at different synthesis temperatures of 800, 900, 1 000℃, and 1 100 ℃, respectively. Effect of powder synthesis temperatures on the dielectric properties of SrBi2Ta2O9 ceramic was investigated. X-ray diffraction results show that single pure phase of SrBi2Ta2O9 can be formed at different temperatures. However, densities of sintered bodies at different temperatures were also found to be different. The pores were relatively smaller and had an even distribution at low synthesis temperature. Further investigation of the dielectric properties implied that the powder synthesis temperature had an obvious influence on the Curie temperature and the dielectric properties. The powders synthesis temperature should be kept as low as possible in order to improve the dielectric properties. Higher synthesis temperature usually causes the formation of large pores, which can result in both shifting of the Curie point and deterioration of the dielectric properties. All these changes can be attributed to pores and defects formed during the sintering process.

关 键 词：固相合成 钽酸锶铋 粉体合成温度 介电性能 CURIE点 

分 类 号：TQ174[化学工程—陶瓷工业]