The deliberate manipulation of grain-boundary crystallography in polycrystals, in order to produce materials having superior properties, was reviewed. Particular attention was paid to annealing twinning, in low stacking-fault energy materials, as a means of achieving the above aim. The role of twinning in improving the grain-boundary network had not yet been satisfactorily explained. Twinning was discussed here from the viewpoint of strain retention, imposition of crystallographic constraints at grain junctions. A new so-called Σ3 regeneration model was used to explain how twins can enhance the Σ3 boundary fraction in the network.

Mechanism of Twinning-Induced Grain Boundary Engineering in Low Stacking-Fault Energy Materials. V.Randle: Acta Materialia, 1999, 47[15], 4187-96