摘要
挠曲电材料在传感、驱动方面呈现出的优良特性,使其在结构健康监测领域具有极大应用前景。挠曲电系数是衡量材料挠曲电效应的重要指标,对其测定受限于微小位移、微小电量的精确测量。本文分析了测定挠曲电系数的关键环节,提出了测定挠曲电系数的实验方案,利用锁定放大器和压电微驱动器以及超景深三维显微镜构建测试平台,精确测量微电量及微位移,进而准确测定挠曲电系数。在室温下对钛酸锶钡(Ba0.75Sr0.25TiO3)试样进行了研究,初步测量了纵向挠曲电系数以及横向挠曲电系数,验证了用该平台测定挠曲电系数的可行性,为进一步开展挠曲电材料的研究和应用提供了基础实验平台。
Flexoelectric materials present an extensive application prospect in the field of structural health monitoring due to its excellent properties in sensing and actuation.Flexoelectric coefficient of dielectric material is an important parameter in judging of material’s flexoelectricity effect.However,the measurement of flexoelectric coefficient is limited by the measuring accuracy of minute displacement and small charge quantity.Based on the analyses of key links in measurement,the experimental scheme was proposed and a test platform composed of lock-in amplifier,micro piezoelectric drive and ultra depth of field three-dimensional digital microscope was built.Minute displacement and small charge quantity can be measured accurately,and then the flexoelectric coefficients can be determined accurately.The longitudinal flexoelectric coefficient μ11and the transverse flexoelectric coefficients μ12of barium strontium titanate（Ba0.75Sr0.25TiO3） were preliminarily measured at room temperature,which demonstrates that the experimental scheme and measurement platform are feasible.Above result provides fundamental experimental platform for further research and application on flexoelectric material.
出处
《实验力学》
CSCD
北大核心
2014年第4期447-452,共6页
Journal of Experimental Mechanics
基金
教育部博士点基金优先发展领域课题资助项目(No.20123227130002)
国家自然科学基金资助项目(No.11272138)
关键词
挠曲电效应
钛酸锶钡
应变梯度
测试装置
flexoelectric effect
barium strontium titanate（Ba,Sr） TiO3
strain gradient
experimental device
