A model had previously been developed in order to study edge dislocations moving over large distances at the atomic scale. It permitted the investigation of the motion of a dislocation under various conditions of applied shear stress, with constant or variable strain rate and temperature, and in the presence of obstacles. The model was used here in order to study the motion of an infinite straight, but flexible, edge dislocation through a row of voids or coherent Cu precipitates in body-centered cubic Fe. The stress-strain curves, energy barrier profiles and strength characteristics of obstacles, and other dislocation-configuration information, were deduced from the modelling results and were compared with continuum treatments. Some specific atomic-scale mechanisms, which were associated with the strengthening due to voids and precipitates with a range of sizes, were observed.

Atomic Modelling of Strengthening Mechanisms due to Voids and Copper Precipitates in α-Iron. Y.N.Osetsky, D.J.Bacon, V.Mohles: Philosophical Magazine, 2003, 83[31], 3623-41