弛豫铁电体/铁电玻璃的电极化机制与应用特性研究

本项目是“铁性玻璃（包括应变玻璃、团簇自旋玻璃、弛豫铁电体/铁电玻璃）理论及性能”（E0105）重点项目群中的项目3。.铁电材料是铁性材料的重要分支，在国防及民用等诸多领域都有重要的应用。目前PZT等传统的铁电材料已经无法满足某些应用需求，而新型包含纳米电畴结构的弛豫铁电体初步显示出许多奇异的特性，为进一步提高铁电材料的性能提供了新的可能。本项目通过研究PMN-PT和BNT-BT等弛豫铁电体的电极化机制及与应用特性相关机理，获得弛豫铁电体纳米电畴、宏畴的形成与演化机制、电畴间相互作用、电畴的电场响应行为及其对性能的影响规律；研究不同类型的铁性玻璃态之间的相互耦合效应；获得弛豫铁电体微结构及性能调控方法；最终构建弛豫铁电体的统一理论模型，并以此指导获得具有宽温区高电光性能铁电陶瓷、高储能密度的弛豫反铁电陶瓷等性能优异的弛豫铁电材料，并在国家重要工程中获得应用。

This project is the third project of the key programs "Ferroic glass (including strain glass, cluster spin glass, relaxor ferroelectrics / ferroelectric glass) theory and properties" (E0105)..Ferroelectrics is an important branch of ferroic materials, and they have very important applications in many military and industry fields. With the advancement of technology, PZT and other traditional ferroelectric materials could not meet requirements for some new applications. The novel relaxor ferroelectrics with nano domain structure show many peculiar characteristics, which provide the possibility for further improving the performance of ferroelectrics. The mechanisms on electric polarization and application characteristics of different relaxor ferroelectrics such as PMN-PT, BNT-BT etc. will be studied in this project. Mechanism for the formation and evolution of polar nanoregion, and macro domain will be obtained. The interaction of different domains, response of domain to the electric field and their effects on properties of relaxor ferroelectric will be clarified. Coupling effect among different ferroic glasses will also be studied. Unified theory for relaxor ferroelectrics and also for ferroic glass will be constructed, and the methods of modification of microstructure and properties will be put forward. Novel relaxor ferroelectrics with excellent properties will be obtained, such as relaxor ferroelectric ceramics with large electric-optic property in wde temperature range, relaxor antiferroelectric ceramics with giant energy density etc. These high performance materials will be used in some important national projects.