Papers by Author: Yuan Gao

Abstract: The defects in crystalline materials significantly affect the fracture behaviors. In this paper molecular dynamics (MD) model using a potential of embedded atom method (EAM) has been developed to investigate the effect of the major crystalline defects, stacking fault and edge dislocation, on the crack propagation in Fe crystal. Six cases with different locations of stacking fault and edge dislocation have been studied. The strain distribution in lattice aggregate was heterogeneous. The dislocations were observed slipping along directions [100] and [-100] on the plane (100). Simulation results showed that the location of the stacking fault and edge dislocation significantly influenced the crack propagation speed.

Abstract: In this paper, molecular dynamics method has been employed to model mode I crack propagation in body center cubic (BCC) single iron crystal. To maximize the simulation efficiency the parallel computing was performed. Six cases with different lattice orientations have been simulated to investigate the crack propagation behaviors at atomic level. The strain distributions have been calculated to indicate the density of dislocation. It has been found that the lattice orientation significantly affects the propagation behaviors. The crack in BCC iron propagates more readily along the direction <111> on the plane {1-10}.