Tanaka Tomohito, Wilkinson Angus J
Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK; Nippon Steel & Sumitomo Metal Corporation, 20-1 Shintomi, Futtsu, Chiba, Japan.
Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK.
Ultramicroscopy. 2019 Jul;202:87-99. doi: 10.1016/j.ultramic.2019.04.006. Epub 2019 Apr 15.
Pattern matching between target electron backscatter patterns (EBSPs) and dynamically simulated EBSPs was used to determine the pattern centre (PC) and crystal orientation, using a global optimisation algorithm. Systematic analysis of error and precision with this approach was carried out using dynamically simulated target EBSPs with known PC positions and orientations. Results showed that the error in determining the PC and orientation was <10 of pattern width and <0.01° respectively for the undistorted full resolution images (956 × 956 pixels). The introduction of noise, optical distortion and image binning was shown to have some influence on the error although better angular resolution was achieved with the pattern matching than using conventional Hough transform-based analysis. The accuracy of PC determination for the experimental case was explored using the High Resolution (HR-) EBSD method but using dynamically simulated EBSP as the reference pattern. This was demonstrated through a sample rotation experiment and strain analysis around an indent in interstitial free steel.
利用全局优化算法，通过目标电子背散射图案（EBSP）与动态模拟EBSP之间的图案匹配来确定图案中心（PC）和晶体取向。使用具有已知PC位置和取向的动态模拟目标EBSP对该方法的误差和精度进行了系统分析。结果表明，对于未失真的全分辨率图像（956×956像素），确定PC和取向的误差分别小于图案宽度的10%和0.01°。尽管与使用传统的基于霍夫变换的分析相比，图案匹配实现了更好的角分辨率，但引入噪声、光学畸变和图像合并对误差有一定影响。使用高分辨率（HR-）电子背散射衍射（EBSD）方法，但以动态模拟EBSP作为参考图案，探索了实验情况下PC确定的准确性。通过无间隙钢中围绕压痕的样品旋转实验和应变分析证明了这一点。
