Mechanical behavior of fcc crystal simulated by 3-D discrete dislocation dynamics

To simulate the mechanical behavior of the FCC crystal with the lower Peierls stress, the stiff property and physical meaning of the differential equation group consisting of dislocation evolution and mechanical state was investigated based on the 3-D discrete dislocation dynamics; the results indicate that the differential equation group is serious stiff, namely the external stress changes more quickly than dislocation evolution. Using the established numerical algorithm, the mechanical behavior of FCC crystal was simulated with the dislocations located in the parallel slip planes, and the effect of strain rate on the dislocation configuration and mechanical behavior, and the saturation process of mobile dislocation were discussed. The simulation results indicate that the numerical algorithm can efficiently simulate the dislocation dipole and the low strain rate loading. © 2008 The Chinese Society for Metals.