The total energy of a wedge-shaped micro- and nanotwin was calculated in terms of a dislocation mesoscopic model. The total energy of the twin was represented as a sum of the elastic energy, energy of interaction between twinning dislocations, and stacking-fault energy of partial dislocations of the wedge-shaped twin. It was found that the evolution of the twin was controlled by the energy of interaction between twinning dislocations: in the case of a microtwin, it was five orders of magnitude higher than the elastic energy and six orders of magnitude higher than the stacking-fault energy. In the case of a nanotwin with the number of twinning dislocations at the twin boundary less than 20, all 3 energies listed above were of the same order of magnitude. Therefore, all the components of the total energy contribute to the origination of a wedge-shaped twin. As the length of the twin increased with its width and the number of twinning dislocations at twin boundaries fixed, the total energy modulo grows although the density of twinning dislocations at twin boundaries decreased. This indicated that long-range stress fields due to twinning dislocations played an important role in the evolution of a wedge-shaped twin.

Energy of a Wedge-Shaped Nanotwin Calculated in Terms of a Dislocation Mesoscopic Model. O.M.Ostrikov: Technical Physics, 2008, 53[2], 199-203