Determining fracture facet crystallography using electron backscatter patterns and quantitative tilt fractography
Determining fracture facet crystallography using electron backscatter patterns and quantitative tilt fractography
复制标题
使用电子背散射图案和定量倾斜断口测定断口晶体学
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
R. Gangloff
中科院分区：
文献类型：
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作者：
D. Slavik;J. Wert;R. Gangloff
提出了一种方法来表征各个断裂表面晶面的晶体学特征。从金相剖面通过小面的电子背散射图案（EBSP）可识别晶粒方向，定量倾斜断口分析可识别小面方向；将这些结果结合起来建立断裂面晶体学。对于该技术，不需要刻面电解抛光，刻面对准过程准确且快速，并且该方法可以推广到不同的微结构、测试环境或刻面方向。说明了未再结晶 Al-Li-Cu 合金 (AA2090) 中 25 至 50 μm 疲劳裂纹面的方法精度，该合金在 10 至 200 μm 厚的细长晶粒中具有 5 μm 厚的亚晶粒。精细的亚晶结构和曲折的疲劳裂纹轮廓使得无法使用其他衍射技术来确定 AA2090 晶面晶体学。 EBSP 和倾斜断口结果表明，AA2090 中的真空疲劳裂纹几乎平行于局部{111}面。
A methodology is presented to characterize the crystallography of individual fracture surface facets. Electron backscatter patterns (EBSP’s) from a metallographic section through a facet identify grain orientation, and quantitative tilt fractography identifies facet orientation; these results are combined to establish fracture facet crystallography. For this technique, facet electropolishing is not required, the facet alignment procedure is accurate and quick, and the method can be generalized to different microstructures, test environments, or facet orientations. Method accuracy is illustrated for 25 to 50 μm fatigue crack facets in an unrecrystallized Al–Li–Cu alloy (AA2090) that has 5 μm thick subgrains in elongated grains that are 10 to 200 μm thick. The fine subgrain structure and tortuous fatigue crack profile precludes the use of other diffraction techniques for determining AA2090 facet crystallography. EBSP and tilt fractography results demonstrate that vacuum fatigue cracks in AA2090 are nearly parallel to local {111} planes.