Pseudo Hall-Petch strength reduction in polycrystalline graphene.

  title={Pseudo Hall-Petch strength reduction in polycrystalline graphene.},
  author={Zhigong Song and Vasilii I. Artyukhov and Boris I. Yakobson and Zhiping Xu},
  journal={Nano letters},
  volume={13 4},
The fracture of polycrystalline graphene is explored by performing molecular dynamics simulations with realistic finite-grain-size models, emphasizing the role of grain boundary ends and junctions. The simulations reveal a ~50% or more strength reduction due to the presence of the network of boundaries between polygonal grains, with cracks preferentially starting at the junctions. With a larger grain size, a surprising systematic decrease of tensile strength and failure strain is observed… Expand
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