Extended stacking faults, with lengths of up to 10nm, that joined {111}/{112} twin-boundary junctions were observed by high-resolution transmission electron microscopy of thin Au films. Circuit analysis showed that these defects possessed a Burgers vector of 1/3<111>. In order to explain the generation of these extended defects, the behavior of 1/3<111> dislocations at {111}- and {112}-type twin boundaries and near {111}/{112} twin-boundary junctions was considered using high-resolution transmission electron microscopic observations and theoretical modelling. By establishing the interaction forces that lead to this defect configuration, the analysis showed that the relief of intrinsic strain at the junction corners, which resulted from the incompatibility of the translation states at the intersecting boundaries, was sufficient to stabilize the stacking fault extension. Because grain–boundary junctions possessed intrinsic strain fields whenever they join boundaries with incompatible translation states, similar mechanisms for stacking fault emission were expected to arise between other closely-spaced grain–boundary junctions.

Stabilization of Extended Stacking Faults by {111}/{112} Twin Junction Interactions. E.A.Marquis, D.L.Medlin, F.Léonard: Acta Materialia, 2007, 55[17], 5917-23