Core structure and mobility of an edge dislocation in aluminum

Abstract

The core structure of an edge dislocation in aluminum is studied by molecular dynamics simulation with the glue potential. The dislocation splits into two partials. The separation distance between the two partials is about 9 Å. The half width of the two partial dislocations is deduced to be 6.5 Å by fitting the Burgers vector density to an arctangent function, giving a half width of the whole dislocation of 12 Å. Dislocation mobility is studied by applying a shear stress on the crystal and observing the corresponding shift of the Burgers vector density. By considering the minor force acting on the dislocation, a Peierls stress in the order of 10 −4 μ for the motion of the whole dislocation in aluminum is obtained.