Dislocation Emission from a Three-dimensional Crack | a Large-scale Molecular Dynamics Study

A series of massively parallel molecular dynamics simulations with up to 35 million atoms is performed to investigate dislocation emission from a three-dimensional crack. We observe dislocation loops emitted from the crack front|the rst time this has been seen in computer simulations. The sequence of dislocation emission in the process of crack blunting process strongly depends on the crystallographic orientation of the crack front and diiers strikingly from anything previously conjectured. This nding is essential to establish a precise dislocation emission criterion (i.e. intrinsic ductility criterion). We also nd that boundary conditions and interatomic force laws have a signiicant eeect on jogging or blunting dislocation emission modes.