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摘要: 利用扫描电镜和透射电镜观测了冲击加载后高纯铝损伤状态孔洞的分布,发现在冲击波加载后,高纯铝中出现了大量的孔洞,孔洞大小多集中在百纳米尺度,分布不均匀,且呈现出带状形貌,局部区域的孔洞在冲击波作用下优先发展,孔洞长大,形成微米级的大孔洞。进一步的观测发现,在孔洞周围出现了大量的位错发射,发射方向位于{111}晶面上,是面心立方金属的密排面。运用分子动力学模拟进行了对比研究,验证了位错发射方向与观测结果是一致的。Abstract: The distribution of micro-voids in aluminum under shock loading has been investigated by means of SEM (Scanning Electron Microscope) and TEM (Transmission Electron Microscope). Results show that plenty of nano-voids have been produced in the shocked aluminum. Most of the void sizes are hundred nanometers. They distribute inhomogeneity, and connect together as a band. Further analysis of the micro-voids indicate that a lot of dislocations are generated around the voids, and the emission direction is in the {111} planes, which are the closed-packed planes of the face-centered cubic metal. The emission direction of the dislocations is excellently agreement with the molecular dynamics (MD) simulation.
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Key words:
- shock wave /
- damage /
- void /
- dislocation
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