燃烧法合成Pb_(1-x)Ca_xZrO_3及其微波介电性能  

Combustion Synthesis and Microwave Dielectric Properties of Pb_(1-x)Ca_xZrO_3

作　　者：田中青[1] 张春艳[1] 黄伟九[1] 

机构地区：[1]重庆工学院材料科学与工程学院,重庆400050

出　　处：《压电与声光》2008年第4期440-442,445,共4页Piezoelectrics & Acoustooptics

基　　金：重庆市自然科学基金资助项目(CSTC2005BA4019)

摘　　要：采用燃烧法合成了Pb1-xCaxZrO3(x=0.3~0.5,摩尔分数)纳米晶粉体,并采用X-射线粉末衍射仪(XRD)、比表面仪和网络分析仪对合成产物的相结构、粉体特性和微波介电性能进行表征。研究结果表明,最佳合成条件是前驱体溶液pH值等于1,甘氨酸与总的金属离子摩尔比(G/M)为1.75,初级粉料的煅烧温度为900℃。合成的粉体为棱形六面体钙钛矿结构,粉体晶粒尺寸在100 nm以下,但存在一定程度的硬团聚。粉体具有良好的烧结性能,在1 250℃下烧结2 h可得相对密度大于96%的致密陶瓷。随x值的增大,Pb1-xCaxZrO3陶瓷的介电常数(rε)从134逐步减少到74,品质因子(Q×f)从2 540 GHz逐步增加到5 120 GHz,谐振频率温度系数(τf)从80×10-6/℃逐步减少到-10×10-6/℃。Nanocrystalline Pb1-xCaxZrO3 （x=0.3^-0.5） powder was synthesized by combustion process. The phase structure, powder characterization and microwave dielectric properties of combustion products were analyzed by X-ray diffraction （XRD）, surface area determination and network analyzer. The optimum synthesis conditions are that pH value of the precursors solution is about 1, the molar ratio of glycine to total metal cations concentration （G/M） equals 1.75, and the calcination temperature is 900 ℃. The XRD results show that the prepared powder is phase pure Pb1-xCaxZrO3 and has a perovskite-type structure with rhombohedral symmetry. The grain size of powder is smaller than 100 nm. The powder shows slight hard agglomeration and good sinterability. The relative density of specimen sintered at 1 250 ℃ for 2 h is higer than 960/00. When x increases, ετ decrease from 134 to 74 and quality factor （Q×f） increases from 2 540 GHz to 5 120 GHz, and the temperature coefficient of frequency τf decreases from 80×10^-6/℃ to -10× 10-^6/℃.

关 键 词：微波介电性能 燃烧法 Pb1--xCaxZrO3 钙钛矿 

分 类 号：TM534[电气工程—电器]