复合添加剂的共沉淀法制备及ZnO压敏陶瓷研究  

Preparation of Composite Additives Powder by Coprecipitation Method and Investgation of ZnO Varistor Ceramics

作　　者：陈培荣[1,2] 季幼章[2] 杨晴[3] 

机构地区：[1]安徽农业大学理学院,合肥230036 [2]中国科学院等离子体物理研究所,合肥230031 [3]中国科学技术大学化学与材料科学学院,合肥230026

出　　处：《无机材料学报》2012年第12期1277-1282,共6页Journal of Inorganic Materials

基　　金：国家自然科学基金(21071136);安徽省教育厅自然科学重大项目(KJ2012ZD11)~~

摘　　要：采用共沉淀法合成的复合添加剂粉体制备ZnO压敏陶瓷,用TG-DTA热分析沉淀物前驱体,通过XRD、SEM、EDS和DLS表征复合粉体的物相、形貌、组成元素、粒度及其分布,测试压敏陶瓷性能、并观察其结构.结果表明,550℃煅烧前驱体生成各添加剂氧化物的混合物;650℃煅烧1 h形成组成为(Bi1.14Co0.26Mn0.29)(Sb1.14Cr0.57Ni0.29)O6.25焦绿石型复合添加剂粉体,复合粉体平均粒径为0.26μm;复合粉体制备的ZnO压敏陶瓷的电位梯度为330 V/mm、非线性系数为47、漏电流为5μA/cm2,电性能参数分别优于固相法混合添加剂粉体制备的压敏陶瓷,这归因于复合粉体制备的压敏陶瓷具有更均匀的显微结构.ZnO varistor ceramic was prepared from composite additives powder synthesized by coprecipitation method. The coprecipitate precursor was investigated by thermogravimetric and differential thermal analysis. Phase formation, morphologies, component elements and particle size distribution of the obtained powder were characterized by X-ray diffraction, scanning electron microscope, energy dispersive X-ray spectroscope and dynamic laser scattering. Electrical properties of the prepared ZnO varistor ceramics were measured, then microstructure features of the ceramics were also observed. The results show that the mixture powder of each additive oxide is obtained by calcination of the precursor at 550℃, while the composite additives powder with pyrochlore-type composition of （Bil.14Co0.26Mn0.29）（SbH4Cr0.57Ni0.29）O6.25 and average particle size of 0.26 p.m is achieved at 650℃for 1 h. ZnO varistor ceramic prepared from the resulted composite additives powder exhibits a higher breakdown voltage （Eb=330 V/mm）, a higher nonlinearity coefficient （α=47） and a lower leakage current （I_L=5 μA/cm2） than that prepared from conventional mixed oxide powder. The improvement in electrical properties is attributed to the more uniform microstructure.

关 键 词：ZNO压敏陶瓷 焦绿石 复合粉体 添加剂 共沉淀 

分 类 号：TQ135[化学工程—无机化工] TB321[一般工业技术—材料科学与工程]