Non-linear features of dislocation emission under mode-II loading were explored at the atomic scale. Crack-tip atomic string models were coupled with a continuum mechanics analysis. The dynamics showed that the atomic motion at the crack tip changed from periodic to chaotic as the mode-II stress intensity factor was increased. The chaotic atomic motion governed dislocation nucleation at the crack tip. A study of the dislocation emission band revealed a cloud-like drifting of the dislocation core ahead of the crack tip.

H.Tan, W.Yang: Journal of Applied Physics, 1995, 78[12], 7026-34