Papers by Author: Sergey V. Dmitriev

Abstract: The molecular dynamics simulation method in two-dimensional case is presented for the simulation of grain refinement and can be applied to the investigation of grain boundary sliding and defects movement under severe plastic deformation. Nanopolycrystalline system is shown as the example of the application of the method proposed. Atomistic details of structure formation and grain growth (refinement) are shown by the example of change of loading scheme. It was shown that elongated grains which appear under plastic deformation can grow up even larger or be destroyed, depending on the direction of the applied maximal shear stresses.

Abstract: We apply the lattice instability analysis to homogeneously strained single crystal with a flat or defected surface to demonstrate that, in the process of emission of dislocation by an unstable surface, prior to the breaking of atomic bonds, a vibrational mode localizes, foretelling the location and the manner of the impending microscopic catastrophic event.