  Using atomistic simulations, dislocation dynamics modeling, and continuum
elastic-plastic stress-wave theory, we present a systematic investigation on
shock-induced plasticity in semi-coherent CuNi multilayers. The features of
stress wave evolutions in the multilayers, including wave-front stress
attenuation and strong interfacial discontinuities, are revealed by atomistic
simulations. Continuum models are proposed to explain the shockwave propagation
features. The simulations provide insight into microplasticity behaviors
including interactions between lattice and misfit dislocations. The formation
of hybrid Lomer-Cottrell locks through the attraction and combination of
lattice and misfit dislocations is a major mechanism for trapping gliding
lattice dislocations at interfaces. The relationship between dislocation
activity and dynamic stress wave evolution history is explored. The hybrid
Lomer-Cottrell locks can dissociate under shock compression or reverse
yielding. This dissociation facilitates slip transmission. The influence of
coherent stress causes direction dependency in the slip transmission: a lattice
dislocation is transmitted more smoothly across an interface from Ni to Cu than
from Cu to Ni. The interaction forces between lattice and misfit dislocations
are calculated using dislocation dynamics code. Lattice dislocation nucleation
from semi-coherent interfaces under shock compression is also reported.
