【作者】 余廷浩；

【导师】 周肇飞；

【作者基本信息】 四川大学 ， 测试计量技术及仪器， 2004， 硕士

【摘要】 众所周知，机械加工表面的质量是决定其功能特性的重要因素，而在应用日益广泛的超精密加工技术中，加工零件的表面质量就更显得重要了，因此对超精细表面微观形貌的检测也成为了现代科技中一个重要的课题。近十多年来，国内外有关学者对超精细加工表面的测试理论及方法进行了大量的研究，提出了许多测量方法和原理，如：机械触针法，光触针法，散射法，等色级条纹法，光学、电子显微法等。 在本文中，作者首先介绍了超精密加工表面微观形貌检测技术的发展，着重分析了目前比较典型的几种表面微观形貌检测方法，指出了它们各自的应用范围和优缺点。在理论研究的基础上，完成了超精密加工表面微观形貌无接触在线检测系统的研制，它主要用于在金刚石车床上测量超精细加工表面的微观形貌及粗糙度，预定测量对象为KDP晶体或非球面透镜。文章还阐述了该测量系统中稳频装置的原理，对其电路进行了详细的分析，在相位测量中引入了AD8302芯片，提高了相位测量精度，简化了系统结构。最后，分析了该测量系统的垂直分辨力和横向分辨力，比较了该系统与美国ZYGO轮廓仪、Taly-6轮廓仪对同一试件的测试结果，证明了研制成功的在线检测仪能够在超精密加工机床上实现纳米级无接触在线检测。 本项目研制的超精细表面微观形貌在线测量系统是以He-Ne激光器双纵模激光为光源的，其工作频率(拍频频率)为728.8MHz。它基于差动干涉原理，且其测量臂和参考臂同轴，这样就使得在垂直方向上的微小位移不会引起光程差，故由测量仪器的振动或空气扰动带来的问题都不会直接影响测量结果，并四川大学硕士学位论文且利用双纵模激光两个模偏振方向正交的特性，设计了双折射晶体分光光路，使反射回光不会影响到光源而引出噪声，光路中虽有不同轴的部分，都安排在晶体中通过，使其不易受外界条件变化的干扰。因此该系统具有杰出的抗振动干扰能力和低噪声性能，当振动干扰达30OIun时，仍可进行亚纳米分辨率的测试，摆放于金刚石车床的刀架上作在线检测时，其垂直分辨率优于0.2nm，横向分辨率优于LS pm。 该在线测量系统根据表面微观形貌对光信号的调制原理，采用了计算机技术进行控制、数据采集与处理，从而实现对表面粗糙度各常用参数的测量，并可以绘出被测表面的轮廓图形。它能够解决要求无损伤、无污染的测量超精细加工表面的问题，且其操作直观简便，测量精度高，重复性好，易加工，不需要特殊的测量环境，具有良好的通用性和性价比。关键词:超精细加工表面在线检测无接触测量表面微观形貌更多还原

【Abstract】 As it is known, the quality of machined surface is one of the important factors that determine its functional character. While in the increasing application of ultra-precision machining technology, the surface quality of machined parts becomes more significant. So the measurement of micro-profile of ultra-precision machining surface is an important task in modern science and technology. In recent ten years, some researchers in the world have made a lot of studies on the measuring methods of ultra-precision machining surface, and have produced some new principles of measurement.After presenting the development of ultra-precision machined surface measuring techniques, the author has analyzed some typical kinds of measuring methods in detail, and has pointed out their characteristics and limitations respectively. Based on theoretical studies, a non-contact on-line measuring system is designed and made, which is mainly applied in measuring the micro-profile and roughness of the ultra-precision machined surface on diamond turning lathe, and the desired measured subject is KDP crystal or non-spherical lens. Besides, the theory of stabilized frequency is expounded, and the analysis of the circuit is made at length. In the phase measurement, AD8302 chip is introduced, which promotes the phase accuracy and simplifies the system structure. Finally, we have analyzed the vertical and lateral resolution of the system, and have compared its measuring result withZYGO and Taly-6 profilometers using the same sample. It has shown that this system can accomplish the on-line nanometer measurement.In this paper, a new on-line measuring profile system is presented, which has a light source of a stabilized He-Ne laser with two longitudinal modes. Based on the principle of differential interferometer, the measurement and reference arms of this profilometer are designed as coaxial. So the vertical micro-displacement cannot introduce errors into optical-distance, and the mechanical vibration and air turbulence has very small effect on the instrument performance. Furthermore, the polarization features of two longitudinal laser is applied to design the optional divided structure with birefringence crystal, thus the noise caused by reflected light back to laser is successfully avoided. Parts of non-coaxial light paths are designed to pass through the crystal, to reduce the disturbance from the environment. In summary, this system has very high resolution and anti-interference feature. Under the circumstance when vibration amplitudes reach 300nm, the profilometer still has sub-nanometer level resolution. The on-line version of the profilometer can be put on the kniferest of a diamond lathe to measure the micro-profile of ultra-precision machining surfaces. The vertical resolution and the lateral resolution are better than 0.2 nm and 0.5 μm, respectively.This online measuring system adopts computer technique to collect and process data. Thus it can measure surface roughness parameters in common use and draw the profile of measured surface. Also, this system can solve the measuring problem of ultra-precision machining surface without damnification and pollution. The operation of the system is convenient, the measuring accuracy is high, and the repetition is fine. In addition, the system, which can be easily made and don’t need special measuring environment, has favorable universality and cost performance.更多还原