Dislocation processes in the deformation of nanocrystalline aluminium by molecular-dynamics simulation

Condensed Matter journal club

Dislocation processes in the deformation of nanocrystalline aluminium by molecular-dynamics simulation

  • Event time: 11:30am
  • Event date: 29th October 2010
  • Speaker: Con Healy (Formerly School of Physics & Astronomy, University of Edinburgh)
  • Location: Room 2511,

Event details

Abstract

The mechanical behaviour of nanocrystalline materials (that is, polycrystals with a grain size of less than 100 nm) remains controversial. Although it is commonly accepted that the intrinsic deformation behaviour of these materials arises from the interplay between dislocation and grainboundary processes, little is known about the specific deformation mechanisms. Here we use large-scale molecular-dynamics simulations to elucidate this intricate interplay during room-temperature plastic deformation of model nanocrystalline Al microstructures. We demonstrate that, in contrast to coarse-grained Al, mechanical twinning may play an important role in the deformation behaviour of nanocrystalline Al. Our results illustrate that this type of simulation has now advanced to a level where it provides a powerful new tool for elucidating and quantifying—in a degree of detail not possible experimentally—the atomiclevel mechanisms controlling the complex dislocation and grain-boundary processes in heavily deformed materials with a submicrometre grain size.
Nat. Mater. 1 45 (2002)

Authors

V. Yamakov, D. Wolf, S.R. Phillpot, A.K. Mukherjee AND H. Gleiter