【作者】 于斌；

【导师】 李旭东；

【作者基本信息】 兰州理工大学 ， 材料学， 2008， 硕士

【摘要】 在各种断裂失效分析手段中,断口分析是最主要的工具,而通过计算机软件分析断口也成为断口研究领域的热点。金属断口的计算机三维重构及定量可视化是金属断口分析的进一步细化研究,能够提供断口完整的三维空间几何信息,为断口定量分析打下了基础。以往基于体视学原理重构的三维断口形貌,需要极其准确的特征匹配算法,且根据二维图像重建三维断口时对断口投影交叠的区域时往往不能重建实际的断口形貌,通过分层切片法重构断口可以突破这个限制,从而得到更真实的断口重构结果。而对断口识别分类大都采用图像处理的方法,没有空间几何的角度去分析,而断口形貌空间几何特征也是特定断裂行为的描述。本文利用分层切片法重构物体的原理,通过图像处理和三维数据场可视化的技术手段,自主开发一套金属断口的宏观形貌三维重构软件JHX_FSR。该软件自动处理由光学显微镜拍摄的一系列断口侧面的宏观切片照片,对断口二维切片图像进行轮廓线特征提取、断口三维数据场的几何校正、轮廓线的插值、断口三维数据场的筛选和轮廓线数据的整合等操作,得到精确的断口三维数据场。通过可视化模块对断口三维数据场重构,得到断口的三维重构结果;并利用定量分析模块对断口局部区域进行定量可视化和定量测量分析。将断口重构结果与实际断面比较,基本一致;将断口重构结果与断口三维数据场校验,实现了断口的精确重构。通过对断口局部区域的定量可视化,验证断口定量可视化结果可以较精确地逼近断口局部区域的形貌特征,断口的定量测量结果可以提供较精确的断口形貌特征的空间几何数据。结果证明,分层切片法重构断口保证了断口三维数据场的精确性,从获取精确的断口三维数据场的角度考虑,是一种有效的断口重构方法,断口三维数据场对断口定量可视化和定量测量具有十分重要的意义。断口宏观形貌特征具有一定的空间几何特征,通过断口三维数据场的定量可视化和定量测量可以描述断口形貌几何特征,断口形貌特定的空间几何特征在断口智能化分析中具有一定的作用和意义。本文全部研究工作是基于自行开发的断口重构与定量可视化软件完成的,该软件为进一步的金属断口智能化研究奠定了一定的基础。更多还原

【Abstract】 Analysis of fracture surface is the most popular tool in the field of fracture analysis, it became the focus of fracture surface research areas to analyze the fracture surface by computer software. The three-dimensional reconstruction technique and quantitative analysis of metal fracture surface is a further research on the analyzing of fracture surface, it can supply all the three-dimensional space geometry data of metal fracture surface, and it provides a base for quantitative analysis of fracture surface.There were several ways to reconstruct the three-dimensional fracture surface in the past, it is very difficult for stereovision principle to reconstruct the real fracture surface from overlapped area of projection of surface in terms of two-dimensional image of fracture surface , however, serial section reconstruction principle can get through this restriction, and get the more precise reconstruction results. The recognition and classification of metal fracture surface were finished by image processing without other criterion in the past, the fracture surface shape characteristics is the characterization of special fracture behavior.In light of the serial cross-sections reconstruction principle, based on the technique of image processing and three-dimensional data sets visualization, this paper develops a software independently ,which is used to reconstruct metallic fracture surface. This software can solve a serial of fracture sample cross-section pictures which was taken by optical microscope, and do a serial of operation, for example, acquirement of the contour characteristics of two-dimensional fracture surface section, the geometric correction of fracture surface’ 3D vector, interpolation of contour data , the filtration of 3D vector of fracture surface and the combination of 3D vector of fracture surface, and then the precise data was get . 3D vector of fracture surface was reconstructed by visualization module, so the results of reconstruction of fracture surface was finished, and the local area of fracture surface was quantitatively visualized by the quantitative analysis module.The result of reconstruction and the real fracture surface are proved to be basically consistent by their comparison, the reconstruction is proved to be high precise by the examination between the reconstruction and 3D vector of fracture surface. The quantitatively visualization of local area of fracture surface conforms to fracture surface shape characteristics, because quantitatively visualization is tested, the quantitative measurement of fracture surface can supply the space geometry data of fracture morphology.The results prove that, it can guarantee the 3D vector of fracture surface precise to reconstruct the fracture surface by serial cross-sections reconstruction principle, it is a good reconstruction method if we want to get high precise 3D vector of fracture surface. We find that fracture surface shape characteristics is similar to space geometry characteristics in the procedure of quantitative analysis of fracture surface . we can describe the fracture morphology by quantitative visualization and quantitative measurement of fracture surface, the intelligent study of fracture morphology is of certain significance for fracture analysis.All research works are based on an independent development software environment of three-dimensional reconstruction and quantitative analysis of fracture surface. It established solid foundation for the further metal intelligent research of fracture.更多还原