Numerical Simulation of Microscopic Dynamic Behavior in the Copper under Explosively Dynamic Loading

Voronoi method was adopted to establish the micro-geometry model of polycrystalline copper which can reflect the irregularities of grain geometric shape and grain boundaries. The Tie-Break model was used to reflect the binding characteristics of grain boundary. Then the grains deformation and thermal deposition behavior under explosive dynamic loading were studied from the microscopic view recur to LS-DYNA nonlinear finite element program. Finally, the possibility of grain refining was analyzed by high pressure melting point theory and grain growth theory, and the analysis was proved qualitatively by experimental results. The results show that it is feasible to research grain and grain boundary deformation mechanisms as well as the heat deposition for the shock compressed polycrystalline copper by the numerical simulation method built in this work. Stress concentration is easy to form on the grain boundaries; plastic deformation and temperature rise on the grain boundaries are greater than those of the grain interior. The temperature rise caused by the macro-adiabatic compression and the micro-plastic deformation does not cause grain growth.