By introducing internal degree, the deformation of hexagonal non-centrosymmetrical crystal sheet could be described by the revised Cauchy–Born rule based on atomic potential. The instability criterion was deduced to investigate the inhomogeneous dislocation nucleation behavior of the crystal sheet under simple loading. The anisotropic characters of dislocation nucleation under uniaxial tension were studied by using the continuum method associated with the instability criterion. The results show a strong relationship between yield stress and crystal sheet chirality. The results also indicate that the instability criterion has sufficient ability to capture the dislocation nucleation site and expansion. To observe the internal dislocation phenomenon, the prediction of the dislocation nucleation site and expansion domain was illustrated by molecular dynamics simulations. The developed method was another way to explain the dislocation nucleation phenomenon.

Inhomogenous Dislocation Nucleation Based on Atom Potential in Hexagonal Noncentrosymmetric Crystal Sheet. X.C.Zhao, X.M.Liu, Z.Zhuang, Z.L.Liu, Y.Gao: Chinese Physics Letters, 2010, 27[1], 016201