Abstract
By a numerical relaxation scheme we have simulated the plastic deformation of a quasicrystal. Shear stress was applied to a quasiperiodic icosahedral atomic configuration of Lennard-Jones particles, and nucleation of dislocation dipoles was observed which move in a slip plane. We also found climb motion and dissociation of a perfect dislocation into a pair of partials. A plane of phasonic defects is left in the wake of the propagating dislocations.