Dislocation density evolution during high pressure torsion of a nanocrystalline Ni–Fe alloy

  title={Dislocation density evolution during high pressure torsion of a nanocrystalline Ni–Fe alloy},
  author={Yanbo Wang and James C. Ho and Yang Cao and Xiaozhou Liao and Hui Li and Yonghao Zhao and Enrique J. Lavernia and Simon P. Ringer and Yuntian Zhu},
  journal={Applied Physics Letters},
High-pressure torsion (HPT) induced dislocation density evolution in a nanocrystalline Ni-20 wt %Fe alloy was investigated using x-ray diffraction and transmission electron microscopy. Results suggest that the dislocation density evolution is fundamentally different from that in coarse-grained materials. The HPT process initially reduces the dislocation density within nanocrystalline grains and produces a large number of dislocations located at small-angle subgrain boundaries that are formed… Expand

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