Measurement of Plastic Strain Distribution by Electron Backscatter Diffraction
Measurement of Plastic Strain Distribution by Electron Backscatter Diffraction
复制标题
通过电子背散射衍射测量塑性应变分布
DOI：
10.2472/jsms.58.568
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
M. Kamaya
中科院分区：
文献类型：
--
作者：
M. Kamaya
用电子背散射衍射仪(EBSD)结合扫描电子显微镜研究了不锈钢中塑性应变在微观组织尺度(局部塑性应变)上的分布。研究了局部方向偏差，即相邻像素之间的方向偏差，以表示局部塑性应变的程度。通过计算来自同一区域的几个数据的平均晶体取向，提高了局部取向测量的精度。结果表明，局部取向不均匀，主要集中在晶界附近。局部取向偏差的分布服从对数正态分布，其平均值与试件中诱发的宏观塑性应变有很好的相关性。利用平均局部取向偏差与塑性应变的相关性，估计了局部塑性应变的分布。将该方法应用于缺口试件非均匀塑性应变的测量，并与有限元分析结果进行了比较，验证了该方法的有效性。
Electron backscatter diffraction (EBSD) in conjunction with scanning electron microscopy was used to assess the distribution of the plastic strain on a microstructural scale (local plastic strain) induced in stainless steel. The local misorientation, which is a misorientation between neighboring pixels, was investigated in order to represent the degree of the local plastic strain. Accuracy of the measurement of the local misorientations was improved by a technique, in which an average of crystal orientation was calculated for several data measured from the same domain. It was shown that the local misorientation was inhomogeneous and localized in the vicinity of grain boundaries. The distribution of the local misorientations followed the log-normal distribution and the mean value correlated well with the macroscopic plastic strain induced in specimens. By using the correlation between the averaged local misorientation and the plastic strain, the distribution of local plastic strain was estimated. This procedure for estimating local plastic strain was applied to measurements of non-uniform plastic stain in notched specimens and its validity was shown by comparing with results of finite element analysis.