Formation mechanism of wide stacking faults in nanocrystalline Al

  title={Formation mechanism of wide stacking faults in nanocrystalline Al},
  author={Xiaozhou Liao and Srivilliputhur G. Srinivasan and Yonghao Zhao and M. I. Baskes and Yuntian Zhu and F. Zhou and Enrique J. Lavernia and Huifang Xu},
  journal={Applied Physics Letters},
A full dislocation often dissociates into two partial dislocations enclosing a stacking fault (SF) ribbon. The SF width significantly affects the mechanical behavior of metals. Al has very high stacking fault energy and, consequently, very narrow SF width in its coarse-grained state. We have found that some SFs in nanocrystalline Al are surprisingly 1.4–6.8 nm wide, which is 1.5–11 times higher than the reported experimental value in single crystal Al. Our analytical model shows that such wide… Expand

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