Grain Boundary Triple Junction Dynamics: A Continuum Disconnection Model

  title={Grain Boundary Triple Junction Dynamics: A Continuum Disconnection Model},
  author={Chaozhen Wei and Luchan Zhang and Jian Han and David J. Srolovitz and Yang Xiang},
  journal={SIAM J. Appl. Math.},
The microstructure of polycrystalline materials consists of networks of grain boundaries (GBs) and triple junctions (TJs), along which three GBs meet. The evolution of such microstructures may be driven by surface tension (capillarity), applied stresses, or other means that lead to a jump in chemical potential across the GBs. Here, we develop a model for the concurrent evolution of the GB/TJ network based upon the microscopic mechanism of motion; the motion of line defects (disconnections) in… 
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