基于空耦超声激励的微结构模态频率温度特性研究  

Study on temperature dependence of modal frequencies for microstructures based on air-coupled ultrasonic excitation

作　　者：佘东生[1] 于震[1] 田江平[2] She Dongsheng;Yu Zhen;Tian Jiangping(College of Control Science and Engineering,Bohai University,Jinzhou 121013,China;School of Energy and Power Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]渤海大学控制科学与工程学院,锦州121013 [2]大连理工大学能源与动力学院,大连116024

出　　处：《国外电子测量技术》2024年第6期127-133,共7页Foreign Electronic Measurement Technology

基　　金：国家自然科学基金(52071064);辽宁省教育厅重点项目(LJKZ1009)资助。

摘　　要：为了研究微悬臂结构弯曲振动模态频率的温度特性,首先针对各向异性材料的等截面矩形微悬臂结构建立了其各阶模态频率温度系数的理论模型;然后搭建了包括激光测振单元、空耦超声激励单元和温度控制单元的非接触式微结构动态特性测试系统;最后利用所搭建的测试系统分别对等截面矩形单晶硅微悬臂梁在室温~300℃时的动态特性进行了测试,获得了微悬臂梁前三阶弯曲振动模态频率随温度的变化规律和频率温度系数。研究结果表明,单晶硅微悬臂梁前三阶弯曲振动模态频率随着温度的升高而呈近似线性的减小,并且微悬臂梁前三阶弯曲振动模态具有几乎相同的频率温度系数,其中一阶模态频率的温度系数为-2.18×10-5/℃,二阶模态频率的温度系数为-1.91×10^(-5)/℃,三阶模态频率的温度系数为-2.01×10^(-5)/℃,前三阶模态频率温度系数的测试结果与理论模型预测值的偏差分别3×10^(-7)/℃,3×10^(-6)/℃和2×10^(-6)/℃。To study the temperature characteristics of flexural vibration modal frequencies for microcantilevers,the theoretical models of temperature-frequency coefficients were established for anisotropic materials microcantilevers with constant rectangular cross-section.Then,a non-contact dynamic characteristic testing system for microstructures was constructed,including a laser vibrometer unit,air-coupled ultrasonic excitation unit,and temperature control unit.Finally,using the established testing system,the dynamic characteristics of single-crystal silicon microcantilevers with constant rectangular cross-section were tested over a temperature range from room temperature to 300℃.The change regularities with temperatures of the first three-order flexural vibration modal frequencies for the silicon microcantilever were figured out,and the temperature coefficients of the first three-order modal frequencies were obtained.The results indicate that the first three bending vibration modal frequencies of the single-crystal silicon microcantilevers approximately linearly decrease with increasing temperature.Moreover,the temperature coefficients of the first threeorder modal frequencies are almost the same.Specifically,the temperature coefficient for the first modal frequency is-2.18×10^(-5)/℃,for the second modal frequency is-1.91×10^(-5)/℃,and for the third modal frequency is-2.01×10^(-5)/℃.The deviations of the test results of the temperature coefficients of the first three modal frequencies from the predicted values of the theoretical model are 3×10^(-7)/℃,3×10^(-6)/℃and 2×10^(-6)/℃,respectively.

关 键 词：空耦超声激励 微结构 频率温度系数 弯曲振动模态 

分 类 号：TH825[机械工程—仪器科学与技术]