【摘要】 铁电陶瓷是具备力电转换功能的典型高技术材料．本文概述铁电陶瓷电致疲劳失效的研究进展．首先介绍电致疲劳的定义和特点,然后讨论电致疲劳失效在不同尺度下的表现行为,包括宏观尺度下裂纹的疲劳扩展;细观尺度下裂纹的萌生;微观尺度下点缺陷在循环电场下的积聚．随即阐述了铁电陶瓷在循环电场下缺陷汇聚的理论分析,运用微结构演化方法计算了单个孔洞随畴界的移动距离,推导了循环电场下铁电陶瓷内点缺陷浓度的演化方程,给出了点缺陷浓度与其汇聚程度之间的定量关系,从而提出了贯通不同尺度的铁电陶瓷电致疲劳失效机理．更多还原

【Abstract】 Researches on electrically introdued fatigue of ferroelectric ceramics are reviewed in the present paper.It’s definition,characteristics and behavors at different scales are introdued,including the growth of fatigue cracks,initiation of microcracks,and agglomeration of point defects.The theory of point defect agglomeration under the cyclic electric field is briefly described.The moving distance of a single void under domain switchings is calculated by the theory of microsructural evolution.The evolution function of point defect concentration in ferroelectric ceramics is derived under the cyclic electric field.The quantitive relationship of point defect concentration and their agglomeration extent are given.The mechanism of electric fatigue of ferroelectric ceramics is elucidated at different scales.更多还原