Shock compression and spallation of tantalum: Molecular dynamics simulations

We perform large-scale molecular dynamics simulations of shock wave compression and spallation of Ta single crystals with different potentials including embedded-atom method (EAM), first-principles-based EAM (qEAM) and reactive forcefield (ReaxFF). Shock loading is applied along $\langle 100 \rangle$, $\langle 110\rangle$ and $\langle111\rangle$. Hugoniot states are obtained from direct shock or Hugoniostat simulations. Anisotropic behaviors are observed in plasticity (including twinning) during compression/tension and in spallation. We present detailed analysis of dislocations, twins and void nucleation and growth, and their implications for the mechanisms of plasticity and spall damage in Ta.