低滞后高线性的大位移压电陶瓷微结构调控及其性能研究

Piezoelectric ceramics with low hysteresis, high linearity and large displacement are crucial for high precision positioning system such as adaptive optics. Hysteresis, linearity and displacement are originated from different mechanisms and they usually interact with each other negatively, so combination and optimization the three kinds of properties in one materials is very difficult. The research on piezoelectric ceramic with low hysteresis, high linearity and large displacement is the frontier in this field. .In this project, high performance piezoelectric ceramic with low hysteresis, high linearity and large displacement are studied. The intrinsic and extrinsic piezoelectric effect in piezoelectric ceramics with different compositions and crystal structures were investigated. The effects of microstructures such as point defects, domain configuration, grain and grain boundary on the piezoelectric properties and hysteresis were also studied. High performance piezoelectric were obtained by designing composition and microstructure from different scales and optiming the three parameters. Multilayer piezoelectric actuators with low hysteresis, high linearity and large displacement were fabricated by the ceramics developed in the project, and the actuators will be used in national important project..The results of the project are very important for the better understanding the correlation between properties and microstructure at different scales. They are also helpful to facilitate the development of new piezoelectric materials and devices.

低滞后、高线性及大位移压电陶瓷是自适应光学等高精度定位系统的关键材料，由于压电陶瓷的滞后、线性及位移均有不同的物理机制，且相互制约，在同一种材料中实现这三种材料特性的有机结合具有相当的难度，因此对此类材料的研究是国际上的前沿及难点课题。本项目针对这类高性能压电陶瓷开展研究，研究不同组分、晶体结构的压电陶瓷的本征及非本征压电效应；研究点缺陷、电畴组态及晶粒晶界等微结构对陶瓷压电性能及滞后的影响。通过以上的研究，从多个尺度对压电陶瓷的组分及微结构进行设计，优化三种材料参数，最终获得高性能的压电陶瓷。利用该压电陶瓷制备低滞后、高线性及大位移的多层压电驱动器，应用于国家重要工程项目。该项目的研究对于深入理解压电陶瓷多层次微结构与性能的关系，进而促进新型压电材料的开发及器件应用都有着重要的意义。

低滞后、高线性及大位移压电陶瓷是自适应光学等高精度定位系统的关键材料，由于压电陶瓷的滞后、线性及位移均有不同的物理机制，且相互制约，在同一种材料中同时优化这三个参数以得到最佳的综合性能具有相当的难度。针对以上的难题，本项目开展了PMNT等多种压电材料制备与性能研究及多层微位移驱动器设计与性能等研究工作，具体包括：系统研究了不同PT含量的PMNT陶瓷的相结构、畴结构、相变及铁电压电性能，获得了PMNT陶瓷相变及电畴对材料压电性能的影响规律，进一步利用晶粒定向技术改变其微结构，获得了具有大应变的PMNT织构化陶瓷；研制了新型的复合钙钛矿结构PZnTe-PZT体系压电陶瓷的结构与性能，获得了同时具有较大压电应变及较低滞后的材料组成；研究了A/B位不同掺杂的PZT压电陶瓷的电学性能，获得了不同离子如Bi3+/La3+、Fe3+/Ga3+/Al3+等掺杂对陶瓷中点缺陷的影响规律、获得了氧空位与自发极化及畴壁的相互作用及其对陶瓷位移与滞后的影响，通过复合离子掺杂获得了d33高达340pC/N、滞后低于4%的压电陶瓷体系，综合性能超过美国PZT-8系列压电陶瓷；利用本项目研制的材料开展了低滞后多层压电微位移器的设计及制备工作，采用电极开槽及环氧灌封提高了器件的可靠性；研究了微位移驱动器的抗拉及老化特性，通过制备工艺优化获得了具有高抗拉强度及良好老化特性的压电微位移器，并提供中物院试用。. 本项目的研究工作在APL等国际学术期刊发表论文9篇，申请国家发明专利3项，已授权1项，培养博士生2名，硕士生1名，培养中物院参研青年1名。. 本项目圆满完成了研究目标，项目的研究结果对于深入理解压电陶瓷多层次微结构与性能的关系，进而促进新型压电材料的开发及器件应用等都有着重要的意义。