Plasticity Induced by Shock Waves in Nonequilibrium Molecular-Dynamics Simulations
Brad Lee Holian,
*
Peter S. Lomdahl
Nonequilibrium molecular-dynamics simulations of shock waves in
three-dimensional 10-million atom face-centered cubic crystals with
cross-sectional dimensions of 100 by 100 unit cells show that the
system slips along all of the available {111} slip planes, in
different places along the nonplanar shock front. Comparison of these
simulations with earlier ones on a smaller scale not only eliminates
the possibility that the observed slippage is an artifact of transverse
periodic boundary conditions, but also reveals the richness of the
nanostructure left behind. By introducing a piston face that is no
longer perfectly flat, mimicking a line or surface inhomogeneity in the
unshocked material, it is shown that for weaker shock waves (below the
perfect-crystal yield strength), stacking faults can be nucleated by
preexisting extended defects.
Theoretical Division, Los Alamos National Laboratory, Los Alamos,
NM 87545, USA.
*
To whom correspondence should be addressed. E-mail:
blh{at}lanl.gov
