【作者】 刘杰；

【导师】 戴福隆；

【作者基本信息】 清华大学 ， 固体力学， 1999， 博士

【摘要】 本文首先阐述了云纹干涉法的基本理论,概括介绍了云纹干涉法的载波技术,并介绍了国内外云纹干涉仪的研究概况及特点。同时对国内外云纹干涉法的应用领域和研究历史及现状进行了概述。 在国内外相关研究的基础上,本文研制出具有独特优点的多功能宏观/细观云纹干涉测试系统,该测试系统可以用于各种环境下的实时测量 三维位移场的同步直接测量是现代光测力学领域中的难题,本文研制的多功能宏/细观云纹干涉仪可以进行三维位移场的测量,并且首次利用载波技术实现了u、v场或u、v、w场的同步测量。作者在云纹干涉仪中使用了偏振相移技术,极大地提高了测量灵敏度。同时作者还研制出可与云纹干涉仪配套使用的多维调节加载系统、小型高温炉和小型低温恒温箱,极大地拓展了云纹干涉仪的应用范围。利用计算机图像采集与分析处理系统,实现了对高温、低温变形的实时测量。本文对该系统的工作原理和功能进行了详细介绍。 本文利用所研制的多功能宏/细观云纹干涉测试系统,对微型硅速度传感器进行了成功的测试,从所获得的实验结果中发现,在生产微型硅速度传感器的工艺中确实存在使其产生初应力的因素。目前对这种微观现象能够进行测试的方法还未见报道。实验取得的结果为国防领域中微型硅速度传感器的生产工艺的改进提供了重要的结果。 利用所研制的多功能宏/细观云纹干涉测试系统,对新型微电子封装组件BGA在低温下的热变形进行了实时观测和分析。实验结果表明,由于热膨胀系数的不匹配,导致了BGA组件焊点上存在着很大的剪切热应变和较大的剪应变集中。实验所获得的封装组件表面热应变的分布结果,是进一步理论分析和数值计算所必须的边界条件。作者在本实验中还通过对试件的剖面和上表面热应变的分别测量验证了测量结果是相同的。 形状记忆合金是一种非常好的智能材料,在微型机械、医疗设备和航空合金设备已被广泛使用。其力学性能如何将直接影响到应用效果和应用范围。作者利用多功能宏/细观云纹干涉测试系统研究了单晶CuAlNi形状记忆更多还原

【Abstract】 First of all, the fundamental theory of Moire Interferometry is elaborated. The carrier fringe technique is introduced. And the development status and background of Moire Interferometer in the world is introduced as well. Moreover, the application, research background and current research progress of Moire Interferometry are introduced.Based on the related investigations, Multifunctional Macro/Micro Moire Interferometer Measurement System with a lot of special advantages is developed. Multifunctional Macro/Micro Moire Interferometer Measurement System can be successfully used to measure both overall and local fields under various environments.The problems of three dimensional measurement are difficult to be solved in modern photomechanics are investigated. Simultaneous measurement of the 3-D displacement fields can be achieved by Multifunctional Macro/Micro Moire Interferometer And simultaneous measurement of 2-D(u,v) and 3-D(u,v,w) displacement fields can be performed by use of carrier fringe techniques. By means of a specially arranged Moire Interferometer, all the 3-D displacement component, u,v,w can be obtained simultaneously at real-time on one image plane, respectively. A kind of device of polarization phase shift is using in the Moire Interferometer, and this device improves measurement sensitivity. Multifunctional Macro/Micro Moire Interferometer Measurement System includes a compact high temperature oven and a compact low temperature oven as well as a six dimensional loading setup. A computer is used to collect and analyze the moire fringe patterns. The principles and functions of this system are discussed in detail in this dissertation.The above system is successfully employed to measure the residual strain of a miniature silicon velocity sensor. The experimental results showed that miniature silicon velocity sensor have initial stresses which is produced bymanufacture technology. The experiments provide very important results which can offer an assist to improve the manufacture technology in the national defense field.The above system is also applied to investigate the thermostrains of a new type of BGA package at such a low temperature as -40°C. The experimental results indicate that the mismatch of the temperature expansion coefficient between two parts jointed by the solder joints results in large shear strains in the solder joints at low temperature. The distributions of the average shear strains on the upper surface and the largest value of the shear strains are gained experimentally. These results are quite valuable for determining border-condition in the theoretical analysis and the numerical simulation. In addition, it is found that the strain distributions in the section plane is identical to those on the upper surface.The Shape Memory Alloys(SMAs) are a smart material. SMAs are widely used in micromechanical, medical instruments and aeronautical facilities. Their mechanical characteristics are the critical factors which will greatly influence their applications. In this dissertation the different mechanical characteristics of CuAINi single crystal shape memory alloys under different temperatures are experimentally studied by Multifunctional Macro/Micro Moire Interferometer Measurement System. The full-field deformation patterns during the martensitic transformation were recorded at both room temperature and high temperature. There are three types of loads. One is that the specimens were loaded by only uniaxial tension, the second is that the specimens were tensidly loaded at a temperature of 107°C, and the third is that the specimens were loaded by the temperature change from 25°C to 133°C. The invariant plane between the martensite and the parent phase is shown directly in these patterns. The experiments demonstrate that growth of the martensite is accomplished by the propagation of individual austenite-martensite interfaces. It is the first time to observe and record the evolution of matensite stripes on the surface of the specimen by Multifunctional Macro/Micro Moire Interferometer during loadingand unloading. The result is important to reveal the mechanism and process of stress-induced matensitic transformation.更多还原