Cooperative grain boundary sliding and migration process in nanocrystalline solids.

نویسندگان

  • S V Bobylev
  • N F Morozov
  • I A Ovid'ko
چکیده

A new physical mechanism or mode of plastic deformation in nanocrystalline metals and ceramics is suggested and theoretically described. The mode represents the cooperative grain boundary (GB) sliding and stress-driven GB migration process. It is theoretically revealed that the new deformation mode is more energetically favorable than "pure" GB sliding and enhances the ductility of nanocrystalline solids in wide ranges of their structural parameters.

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عنوان ژورنال:
  • Physical review letters

دوره 105 5  شماره 

صفحات  -

تاریخ انتشار 2010