A mechanism of twin formation from 2 Shockley partial dislocations on non-neighboring glide planes was reported. Further, the driving force of twin nucleation was correlated with a local stress of high magnitude. Using the embedded atom method potential for atomic interactions, the molecular dynamics simulations of Cu nanograins and a single crystal revealed the formation mechanism and identified the driving force. Stacking faults expanded under high stress, increasing their energy and making their transformation to a twin energetically favorable. Although this study focused only on Shockley partial dislocations on non-neighboring glide planes, the driving force (a stress of high magnitude) was also expected to apply to twin formation from Shockley partial dislocations on neighboring glide planes.

Shockley Partial Dislocations to Twin - Another Formation Mechanism and Generic Driving Force. J.Wang, H.Huang: Applied Physics Letters, 2004, 85[24], 5983-5