淬火对层状钙钛矿铁电材料性能的影响  

EFFECT OF QUENCHING ON PROPERTIES OF BISMUTH LAYERED-STRUCTURE FERROELECTRICS

作　　者：朱骏[1] 王伟[1] 毛翔宇[1] 陈海涛[1] 陈小兵[1] 

机构地区：[1]扬州大学物理科学与技术学院,江苏扬州225002

出　　处：《硅酸盐学报》2010年第12期2275-2278,共4页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(10274066);江苏省自然科学基金(BK2005052)资助项目

摘　　要：研究了不同的淬火温度对层状钙钛矿结构铁电陶瓷SrBi4Ti4O15和Sr2Bi4Ti5O18的微结构、铁电性能与介电性能的影响。经过不同温度淬火后,两种样品的微观结构基本不变,但淬火温度高于Curie温度时,其铁电性能改善明显,表现为剩余极化强度增大,回线的矩形度变好,矫顽场基本不变。SrBi4Ti4O15经过600℃和800℃淬火后,剩余极化强度分别提高约35%和88%。Sr2Bi4Ti5O18经过400℃淬火后,剩余极化强度提高约28%。淬火同时还使样品的相对介电常数增加,介电损耗减小。淬火对介电性能的改善与经淬火后材料中氧空位等缺陷的动性减弱、在畴壁处的聚集减少及铁电畴易于翻转有关。Effect of quenching on microstructure,ferroelectric and dielectric properties of bismuth layer-structured ferroelectrics SrBi4Ti4O15 and Sr2Bi4Ti5O18 were investigated.The microstructure of these two samples does not change after being quenched at different temperatures.Their ferroelectric properties are improved significantly when quenched at high temperature（above Curie temperature）.Remanant polarizations are increased while coercive fields hardly change.For SrBi4Ti4O15 quenched at 600 ℃ and 800 ℃,the remanant polarization is increased by 35% and 88% in comparison with that of the unquenched sample.The remanant polarization of Sr2Bi4Ti5O18 is increased by 28% after being quenched at 400 ℃.In addition,the dielectric measurement suggests that quenching can increase relative dielectric constant and reduce dielectric loss.Quenching above the Curie temperature can weaken defects mobility,such as oxygen vacancies.This decreases the accumulation of the defects at domain boundary and reduces the domain pinning,resulting in easy switching of the ferroelectric domains.

关 键 词：层状钙钛矿 剩余极化 缺陷 淬火 CURIE温度 

分 类 号：O482.54[一般工业技术—材料科学与工程] TM271.4[理学—固体物理]