(Ba(1-x)Cax)1-1.5yBiyTiO3陶瓷的介电弛豫行为和线性介电响应  

DIELECTRIC RELAXOR BEHAVIOR AND LINEAR DIELECTRIC RESPONSE OF (Ba_(1-x)Ca_x)_(1-1.5y)Bi_yTiO_3 CERAMICS

作　　者：云斯宁[1] 王晓莉[2] 徐德龙[1] 李辉[1] 罗平生[2] 孙晓量[2] 杨雪[2] 乌李瑛[2] 

机构地区：[1]西安建筑科技大学材料科学与工程学院,西安710055 [2]西安交通大学理学院,西安710049

出　　处：《硅酸盐学报》2008年第3期271-276,共6页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(50272052;50772087)资助项目

摘　　要：采用传统的电子陶瓷工艺制备了(Ba1-xCax)1-1.5yBiyTiO3(x=0.10,0.20,0.30,0.40,0.50;y=0.05)陶瓷,研究了介电弛豫行为和线性介电响应。X射线衍射分析表明:摩尔分数为5%的Bi3+能够完全溶入Ba1-xCaxTiO3固溶体的钙钛矿晶格。与Ba1-xCaxTiO3陶瓷相比,(Ba1-xCax)1-1.5yBiyTiO3陶瓷表现出与铅基弛豫铁电体相似的介电弛豫行为。在(Ba1-xCax)1-1.5yBiyTiO3陶瓷样品中,发现了罕有的不同于正常铁电体和弛豫体的线性介电响应:在电场强度(E)接近于零的地方,极化强度(P)-E回线近似于线性变化,电流密度(J)-E回线呈现明显的双峰,电滞回线总体呈现"束腰"效应。(Ba1-xCax)1-1.5yBiyTiO3陶瓷样品表现出的这种异常介电行为归因于缺陷偶极距所产生电场的遏制作用。The dielectric relaxor behavior and linear dielectric response of （Ba（1-x）Cax）1-1.5yBiyTiO3（x =0.10, 0.20, 0.30, 0.40, 0.50; yffi0.05） ceramics prepared by the conventional ceramics preparation technique were investigated. X-ray diffraction patterns indicate that 5% （in mole） of Bi3＋ doping can be fully incorporated into the perovskite lattice of （Ba1-xCax）TiO3. Compared with （Ba1-xCax）TiO3 ceramics, the （Ba1-xCax）1-1.5yBiyTiO3 ceramics samples shows a typical dielectric relaxor behavior, similar to lead-based relaxor ferroelectrics. Unlike normal ferroelectrics and relaxors, an unusual linear dielectric response was found in the （Ba1-xCax）1-1.5yBiyTiO3 ceramics samples, the polarization （P）-electric field （E） relationship is close to linear; the current density（J）-E relationship is a double peak, and the hysteresis loop shows a generally shrinking effect when the electric field is close to zero. The abnormal dielectric behavior may have been due to an electric field-induced defective dipole.

关 键 词：钛酸钙钡 介电弛豫 线性介电响应 掺杂 缺陷 

分 类 号：TM22[一般工业技术—材料科学与工程]