Abstract
The nanodisturbance deformation mode is theoretically described as a specific physical mechanism of plastic flow in nanowires with a fcc crystal structure. The mode represents formation and evolution of nanodisturbances—nanoscopic areas of ideal plastic shear with tiny shear vectors—in mechanically loaded nanowires. We calculated the energy and stress characteristics for the formation of both isolated nanodisturbances and their groups (whose evolution results in nucleation of deformation twins) in Au and Cu nanowires having square cross sections. It is shown that the nanodisturbance deformation mode tends to dominate over conventional dislocation generation and glide in Au and Cu nanowires (with flat free surfaces) at high stresses and zero temperature. In these nanowires, the critical stress for the formation of isolated nanodisturbances and that for nucleation of deformation twins is sensitive to the nanowire width. The sensitivity corresponds to the “smaller is stronger” tendency.
6 More- Received 24 April 2010
DOI:https://doi.org/10.1103/PhysRevB.83.054111
©2011 American Physical Society