QQ客服 官方微博 反馈留言

	PZT／Ag功能复合材料的介电常数异常
	张海龙 ; 李敬锋 ; 张波萍 ; ZHANG Hai-Long ; LI Jing-Feng ; ZHANG Bo-Ping
	2010-06-10 ; 2010-06-10
关键词	PZT／Ag 复合材料 介电常数 PZT/Ag composite dielectric constant TQ174
其他题名	Dielectric Constant Anomaly in PZT/Ag Functional Composites
中文摘要	以PZT和纯Ag粉末为原料,在1200℃下用普通粉末烧结工艺制备了PZT／Ag复合材料．尽管烧结温度超过了Ag的熔点,Ag粉末并未氧化,也未与PZT相中的Pb发生反应形成合金,而是以单质Ag的形式弥散分布在PZT基体中,并且PZT／Ag界面结合良好, 同时发现有微量的Ag替代Pb进入了PZT的晶格位置．在0-15vol％Ag成分范围内研究了 PZT／Ag功能复合材料的介电性能,发现其介电常数εr随Ag含量的变化表现为先降后升(临界成分点:1vol％Ag)的趋势,并不符合用于预测介电体中添加导电第二相引起介电常数增加的经典Maxwell方程．在钙钛矿结构A位离子取代和渗流效应的理论基础上解释了上述介电常数的异常变化,认为是由于在低成分范围内,Ag+取代Pb2+降低介电常数εr并起主导作用;随着Ag含量的增加,Ag第二相颗粒之间建立的有效介电场增加了介电常数并逐渐起主导作用．; The PZT/Ag composites were fabricated via conventional powder processing at 1200℃ by using PZT and Ag powders as the starting materials. Although the sintering temperature being higher than melting point of Ag, the pure Ag particles were homogeneously dispersed in the PZT matrix with sound PZT/Ag interfaces, and no metallic alloys between Ag and Pb were formed. At the same time, a small quantity of Ag was found to diffuse into the Pb-lattice. In the range of 0-15vol% Ag, the dielectric properties of the PZT/Ag composites were investigated. The results show that the relative dielectric constant εr first decreases when Ag concentration is <1vol%, and then increases gradually up to 15vol%. This dielectric constant anomaly was explained on the basis of A-site cation substitution of perovskite structure as well as the percolation theory. In the lower Ag concentrations, the Ag+ substitutes Pb2+ and decreases the dielectric constant and this is the dominant mechanism; with the increase in Ag concentration, the effective dielectric field is established to increase the dielectric constant and it gradually becomes the dominant mechanism.; 国家自然科学基金(50325207,50402002) 博士后科学基金(2004036047)
语种	中文 ; 中文
内容类型	期刊论文
源URL	[http://hdl.handle.net/123456789/61345]
专题	清华大学
推荐引用方式 GB/T 7714	张海龙,李敬锋,张波萍,等. PZT／Ag功能复合材料的介电常数异常[J],2010, 2010.
APA	张海龙,李敬锋,张波萍,ZHANG Hai-Long,LI Jing-Feng,&ZHANG Bo-Ping.(2010).PZT／Ag功能复合材料的介电常数异常..
MLA	张海龙,et al."PZT／Ag功能复合材料的介电常数异常".(2010).

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。