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
  • Graduation date
    Spring 2012
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • 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.