Visualization of stacking faults in fcc crystals in plastic deformations

Using molecular dynamics simulation, we investigate the dynamics of stacking faults in fcc crystals in uniaxial stretching in a Lennard-Jones binary mixture composed of 4096 particles in three dimensions. We visualize stacking faults using a disorder variable $D_j(t)$ for each particle $j$ constructed from local bond order parameters based on spherical harmonics (Steinhardt order parameters). Also introducing a method of bond breakage, we examine how stacking faults are formed and removed by collective particle motions. These processes are relevant in plasticity of fcc crystals.