Numerical Simulation of Dislocation Motion in an Icosahedral Quasicrystal

In a large number of experiments it has been shown that plastic deformation of quasicrystals can occur by a dislocation mechanism. By molecular dynamics simulations close to zero temperature we have investigated the application of shear stress to a three-dimensional model quasicrystal consisting of Lennard-Jones particles and containing an edge dislocation of the Peierls-Nabarro type. Various visualization methods have been used to trace the dislocation line. To determine suitable Burgers vectors we have calculated the gamma surface, i.e. the misfit energy obtained by a rigid shift of two probe halves along a glide plane. Glide motion of the dislocation on different glide planes was observed. In its wake a plane of phasonic defects was detected.