Fig. 1. Loading scheme of the simulated nanocrystal. The tension direction is shown by arrows, blue and red spheres are atoms of two (111) planes which will contain a stacking fault, and the red frame is a fragment for analyzing atomic rearrangements due to a partial dislocation passing through it.

Fig. 2. Stacking fault propagation in the loaded crystallite. Projection of two (111) atomic planes at (a) 10?ps and (b) 50?ps with the indication of atoms whose immediate surrounding belongs to fcc (blue), hcp (cyan), bcc (black), and uncertain lattice type (red). Elementary lattice cells in the plane of stacking fault propagation (с).

Fig. 3. Atomic rearrangements during fcc→bcc→hcp transformations according to the molecular dynamics simulation. Crystallite fragments at (a) 0?ps, (b) 0.15?ps, (c) 0.20?ps, and (d) 0.25?ps with the indication of atoms whose immediate surrounding belongs to fcc (blue), hcp (cyan), bcc (black), and uncertain lattice type (red). bp = а6/6 corresponds to the shear induced by a Shockley dislocation (b = (а/6) [12?1]).

Fig. 4. Atomic displacements as a function of time for one of the atomic rows during fcc→bcc→hcp transformations.

Fig. 5. Atomic rearrangements during fcc→bcc→hcp transformations according to the geometrical model. Atomic configurations at different stages of transformations localized in two adjacent slip planes and responsible for the formation of a Shockley dislocation: (a) initial; (b) after tension-compression and shear during direct transformation; (c) after reverse transformation. The atomic configurations in the left column are in the section parallel to the (111) slip plane, and those in the middle column are in the section parallel to the (101?) plane, which is perpendicular to the slip plane and contains a Burgers vector, and the right column represents a 3D view of atomic configurations. The color of atoms corresponds to fcc (blue), hcp (cyan), and bcc (red) symmetry of local environment.