Simulation of the (001) plane crack in α-iron employing a new boundary scheme

A new boundary scheme for atomic-level computer simulations in solid mechaisms has been developed which is based on the finite-element method and which provides several advantages over previous boundary schemes. This has been applied to the simulation of (001) plane two-dimensional cracks in ac-Fe having crack line directions of [010] and [110]. Significant differences between the cracks in these two directions were observed. Lattice-trapping limits and some information on the magnitude and shape of the crack-tip displacement field is provided for both cases. No dislocations were emitted at low temperatures, but warming the model to 400 K apparently resulted in the emission of a dislocation from the crack-tip.