A special mechanism of dislocation nucleation in deformed nanocrystalline materials was suggested and theoretically described. The mechanism represented non-local homogeneous nucleation of a nanoscale loop of so-called non-crystallographic partial dislocation whose Burgers vector magnitude continuously grew during the nucleation process. It was shown that the special mechanism could effectively produce nanoscale loops of lattice and grain boundary dislocations in nanocrystalline materials deformed at high mechanical stresses.

Special Mechanism for Dislocation Nucleation in Nanomaterials. M.Y.Gutkin, I.A.Ovidko: Applied Physics Letters, 2006, 88[21], 211901 (3pp)