高性能无铅压电材料Ba(Zr,Ti)O3-(Ba,Ca)TiO3准同型相界亚畴结构与压电性能相关性的研究

项目名称： 高性能无铅压电材料Ba(Zr,Ti)O3-(Ba,Ca)TiO3准同型相界亚畴结构与压电性能相关性的研究

项目编号： No.51207121

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 电气科学与工程学科

项目作者： 高景晖

作者单位： 西安交通大学

项目金额： 26万元

中文摘要： 压电电介质材料被广泛应用在电子器件中。最近，在一种新型无铅压电陶瓷材料Ba(Zr0.2Ti0.8)O3-(Ba0.7Ca0.3)TiO3（简称BZT-BCT）中，发现了与传统铅系Pb(Zr,Ti)O3陶瓷同量级的巨大压电系数,使得该无铅压电材料有望取代有毒铅系材料。然而，目前对BZT-BCT材料压电机理的探究工作尚不充分，特别是该材料的结构-性能关系，即压电性能与内部电畴结构的相关性还未被研究。本项目拟采用透射电子显微技术，表征BZT-BCT压电陶瓷在准同型相界附近成分的铁电畴形貌以及晶体结构演化，并结合压电性能测试，建立该体系电畴结构与压电性能的相关性。同时，本项目还将研究电畴结构的动态过程对于压电性能的贡献。此外，拟根据实验结果，建立铁电畴结构与压电性能关系的理论模型。本项目的提出，旨在理解BZT-BCT材料巨大压电性能的物理机理，对开发新型无铅压电材料提供重要指导。

中文关键词： 功能电介质材料；无铅压电材料；压电效应；亚畴结构；

英文摘要： Developing Pb-free piezoelectric material is an important issue in solid state physics, aiming to replace the widely-used toxic Pb-based piezoelectrics. However, most of the existing Pb-free piezoelectric materials are inferior to Pb-based systems in piezoelectricity. Very recently, a new Pb-free piezoceramic has been reported in a Ba(Zr0.2Ti0.8)O3-(Ba0.7Ca0.3)TiO3 (abbreviated as BZT-BCT)compound, which exhibits high d33 comparable with the conventional Pb(Zr,Ti)O3 system. Nevertheless, the reason for such strong piezoelectricity in Pb-free BZT-BCT system is not clear; in particular, its microstructure-property relationship has not been revealed. This funding is proposed with the purpose of establishing the relationship between strong piezoelectricity and the domain structure in BZT-BCT piezoceramic. Firstly, the domain structure and crystal symmetry feature of BZT-BCT close to morphotropic phase boundary compositions will be characterized by transmission electron microscopy. Its relationship with piezoelectric property will be established in combination with further piezoelectricity characterization. Secondly, the domain dynamics will be studied by considering its contribution to piezoelectricity. Thirdly, a theoretical model based on our experimental observation will be proposed in order to understand the ph

英文关键词： Functional dielectric material；Pb-free piezoelectric materials；piezoelectric effect；subdomain structure；