Dislocation movement over the Peierls barrier in the semi-discrete variational Peierls framework

A new method has been developed to calculate the Peierls stress (tau(p)) in the semi-discrete variational Peierls framework. It provides a physically transparent view of the variation of the dislocation core while overcoming the Peierls barrier, and with a minor extension it can simulate the coordination between leading and trailing partial dislocations. Calculations show that the relaxation of the slip profile reduces the Peierls stress and the unstable stacking fault energy plays a critical role in determining tau(p) (C) 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.