Formation of two conjoint fivefold deformation twins in copper nanowires with molecular dynamics simulation

The formation of two conjoint fivefold deformation twins (DTs) in copper nanowires under bending is reported based on molecular dynamics simulations. It is found that an intermediate icosahedral phase is formed to facilitate the transformation from a low dense (010) plane in a face-centered-cubic lattice to a {111} close-packed fashion, forming trijunctions composed of three DTs. These trijunctions can easily interact with other DTs, forming two conjoint fivefold DTs. This formation process differs from the one observed by Cao and Wei [Appl. Phys. Lett. 89, 041919 (2006)], that is, fivefold DTs could be formed without introducing initial imperfections in simulations. (c) 2008 American Institute of Physics.