Study of the atomic structure of bcc and fcc crystals upon instantaneous plastic deformation
Аннотация
The evolution of the atomic structure of face-centered cubic (fcc) and body-centered cubic (bcc) crystals under the conditions of pulsed external loads and large plastic strains is investigated on the basis of computer experiments. The crystals are strained in steps to 32%. After each deformation step (2%), the system is relaxed by molecular dynamics to a new equilibrium state at 300 K. The results of the computer experiments show that plastic deformation can take place under instantaneous external loads either as a result of the motion of partial dislocations, twinning, or the turning and displacement of atomic planes, depending on the stage of the process. The laws governing the variation of the potential energy of the system and the rotation angle of the atomic planes as functions of the degree of plastic strain of the crystal are found.