【作者】 李丽娟；

【导师】 安志勇；

【作者基本信息】 长春理工大学 ， 光学工程， 2005， 博士

【摘要】 冷轧钢板表面微观轮廓精度被认为是加工过程中最重要的控制参数之一。它不仅会影响钢板与模具之间的摩擦因数、储油条件及钢板冲压时的成形性能，还会影响到钢板表面的反射性和着色性等性能。随着光电技术、激光技术和计算机技术的发展与广泛应用，为表面微观轮廓精度的检测提供了新的理论与技术，以这些理论技术为基础发展起来的非接触光电检测技术已成为现代产品质量检测的重要手段。本文就是针对冷轧钢板表面微观轮廓精度应用非接触光电检测技术研究的一种可对多参数进行实时在线测量的技术与系统。 本文以Beckmann光散射理论为基础设计了钢板表面微观轮廓精度测量系统。文中针对光在介质表面的散射特性，分析探讨了Beckmann标量积分理论、Rayleigh-Rice矢量微扰理论、S-C-S矢量积分理论等各种散射理论的基本分析方法、假设条件及各自的适用范围，并且以Beckmann光散射理论为基础，建立光散射模型，分析推导了光散射和粗糙度测量间的定量关系，建立了粗糙面的近似表达式。将其应用在冷轧钢板表面微观轮廓精度的测量中，并由此建立了冷轧钢板表面粗糙度参数轮廓算术平均偏差Ra、自相关长度T的数学模型，从而确立了镜面反射光强和表面粗糙度之间的定量关系。在此基础之上，设计了表面粗糙度参数Ra测量分系统和每英寸波峰数PPI测量分系统。 在Ra测量分系统中，为了得到钢板表面的Ra参数值，需分别测量入射光的光强和镜面反射光的光强，而对入射激光波长的选择及对激光入射角的选择是测量技术的关键。通过对入射激光波长与表面镜面反射率的关系谱线的测量分析和实验研究，以及对0.6328μm和3.39μm入射激光的镜面反射光强度的测量分析和实验研究等，选用了波长为3.39μm的氦氖激光器做激光光源。同时，通过理论计算和实验结果分析，认为光束入射角为75°时是最佳角度。另外，在Ra测量分系统中，还设计了标准量校准系统，借助于表面轮廓算术平均偏差Ra值已知的标准冷轧钢板，在同样条件下测量被测钢板和标准钢板，并比较它们的测量结果，以此来校准光路的准确性和确定工件的合格与否。该分系统可测量轮廓算术平均偏差Ra的范围为0.1μm到1.8μm。 PPI测量分系统中，采用轮廓基准中线上方1／2Ra处作为阈值进行高点计数，得到被测轮廓每英寸的波峰数目PPI。依据实验数据，分析了不同阈值下T与PPI的关系，确立了1／T与PPI基本成正比的关系。依据Beckmann粗糙表面散射光空间分布的基本模型，推导出可用于实际计算的金属表面散射光功率分布的近似模型，并对冷轧钢板表面散射光的空间分布进行了数值模拟。系统采用波长0.635μm的半导体激光器做光源，光束以0°入射角垂直投射到被测表面，光能量的接收采用硅光电池。该系统PPI的测量范围可达600点。 信号采集和数据处理系统中，光强信号被转换为电压信号，信号放大后通过数据采集和模数转换，被送入计算机。根据R_a和PPI的数学模型，采用Visual Basic6.0编更多还原

【Abstract】 The precision of the surface microcosmic profile of the cold-rolled plate has been considered the one of the most important controlling parameters of the machining process. It can affect the friction factor between the steel plate and mould. It also affects the oil storage condition between the steel plate and mould and then affects the figuration capability during the steel plate pressing. The quality of steel plate surface such as reflecting and bepainting also can be affected. With the development and appliance of the photoelectric technique、 laser technique and computer, a new tool has been applied to the precision measuring of the surface microcosmic profile. The non-contact photoelectric measuring technology based on this new theoretical technique has become the important tool of the modern product quality measuring. The system of the precision measuring of the surface microcosmic profile of the cold-rolled plate was a multi-parameter、real time and online measuring system that can apply to non-contact photoelectric measuring technology.This article based on the Beckmann’s light scattering theory designed the system of the precision measuring of the surface microcosmic profile of the steel plate. The article talked about the scattering characteristic of light on the medium surface and analyzed the basic analysis method、 hypothesis condition and the application of the Beckmann’s scalar integral theory、 rayleigh -Rice’s SPM theory、 S-C-S vector integral theory and other scattering theories. It also founded the light scattering model and analyzed the ration relation between the light scattering and the roughness measuring and established the approximate expression of the roughness surface. So it can be applied to the precision measuring of the surface microcosmic profile of the cold-rolled plate. And then we founded the model of the profile arithmetic average error Ra and the model of correlation length T of the cold-rolled steel surface, so that we can establish the ration relation between the specular reflection and surface roughness. Based on it, we designed the subsystem to measure the surface roughness Ra and the peeks of per inch (PPI) .In the measuring subsystem of Ra, in order to get the Ra value of the measured surface, we must measure the light intensity of the incident light and the specular reflect light. Moreover it is the key of the measurement that the choice of the wavelength of the incident light and the incidence angle. Through the analysis and the experiment of spectrum relation of the wavelength of the incident laser light and the reflectivity of the steel surface, and through the research of the intensity of the specular reflected light of the incident lights which wavelength is 0.6328 μm and 3.39 μm, we considered the 3.39 μm wavelength He-Ne laser as the light source. At the same time, through the theoretical calculate and analyses of test result, the incident angle 75° can be considered as the best angle. Otherwise,更多还原