A reference model for molecular dynamics simulations was proposed. On the basis of this model, a flexible displacement boundary scheme was introduced in which the dislocations which were emitted from a crack tip could pass continuously through the border of the inner discrete atomic region, and pile up at the outer continuum region. The effect of emitted dislocations within the plastic zone, upon the inner atomistic region, was clearly demonstrated. Simulations for a Mo crystal showed that a full dislocation in a body-centered cubic crystal dissociated into 3 partial dislocations, and interactions between the crack and the emitted dislocations resulted in a gradual decrease in the local stress intensity factor.

Correlative Reference Model and Molecular Dynamics Simulation of Dislocation Emission Process. Q.Tang, T.Wang: Computational Materials Science, 1998, 12[2], 73-83