Molecular dynamics simulations of dislocations behavior in KCl crystal under uniaxial compression along the , , and  axis directions were performed to discuss the elastoplastic transition under shock compression. The simulation results showed that the dislocation moved along about 45 deg to the uniaxial compression direction through the displacements of atomic lines around the dislocation core. Under uniaxial compression along the  axis direction, two extra half-(011) planes were inserted as dislocations in KCl crystal. The minimum stress for dislocation motion under the uniaxial compression along the  axis direction was much larger than those under the uniaxial compressions along the  and  axis directions. It was suggested that the large minimum stress for dislocation motion along the  axis direction was caused by the existence of two edge dislocations which were inserted as extra half-(011) planes. This anisotropic behavior was consistent with the experimental measurement of Hugoniot-elastic limit.
ASJC Scopus subject areas
- Physics and Astronomy(all)