Mechanism of grain growth during severe plastic deformation of a nanocrystalline Ni-Fe alloy

  title={Mechanism of grain growth during severe plastic deformation of a nanocrystalline Ni-Fe alloy},
  author={Yanbo Wang and James C. Ho and Xiaozhou Liao and Hui Li and Simon P. Ringer and Yuntian Zhu},
  journal={Applied Physics Letters},
Deformation induced grain growth has been widely reported in nanocrystalline materials. However, the grain growth mechanism remains an open question. This study applies high-pressure torsion to severely deform bulk nanocrystalline Ni-20 wt % Fe disks and uses transmission electron microscopy to characterize the grain growth process. Our results provide solid evidence suggesting that high pressure torsion induced grain growth is achieved primarily via grain rotation for grains much smaller than… Expand

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