A molecular dynamics simulation study on the deformation behavior for nanotwinned polycrystalline copper

• Author / Creator

  Marchenko, Arina

• Present research is focused on the mechanical behavior of nanoscale
  copper with growth twins. Atomistic calculation (Molecular Dynamics
  simulation) with embedded-atom method potential was used to study the
  fundamental deformation processes that occur in columnar nanocrystalline
  copper. The research also investigates the influences of twin spacing and grain
  size on the deformation characteristics and properties of materials. Simulation
  results have shown that a material’s strength and toughness can be enhanced by
  introducing twin boundaries within nanocrystalline grains. Nanotwins act as
  obstacles to dislocation motion that leads to the strengthening of nanotwinned
  structures, as well as sources of dislocation nucleation contributing to the
  toughness of the materials. The enhancement of the properties is more
  pronounced when the twin boundaries are close enough to the grain boundaries.
  At extremely small distance, the strength of the nanotwinned models is found to
  exhibit an inverse relationship. The deformation behavior in different grains
  depends upon their orientation with respect to the loading direction. The study
  has also revealed that grain-size refinement in nanotwinned models may
  deteriorate materials properties.

• Subjects / Keywords

  • Strength and toughness
  • Grain and twin boundaries
  • Plastic deformation of nanocrystalline copper

• Graduation date

  Spring 2012

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3CS6G

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.