Numerical simulation on high speed impact behavior of Al-W and Al-Ni mixture

Multi-functional energetic structural material (MESM) is a mixture of metals, metal oxides and binders, which improves the insensitivity and maintains explosion power of the explosives. MESM during explosion reaction undergoes various changes in thermal, mechanical, and chemical characteristics caused by shock wave propagation in time scale of nanoseconds. It is hard to study impact characteristics of MESM through various experiments due to short impact reaction, high cost and safety problem. Therefore, analysis using mesoscale simulation is important in studying impact characteristics such as Hugoniot relation and pressure data. In this study, meso-scale simulations of shock wave propagation were conducted for Al, Ni, W, Al-W and Al-Ni mixture, under the conditions of impact velocities ranging from 0.5 km/s to 5 km/s. Simulation data of Al, W and Ni using Mie-Gruneisen EOS were used to confirm the accuracy of analysis, and the results correlated reasonably well with the corresponding data (Los Alamos explosive experiment). Based on this single metal simulation results, simulations for Al-W and Al-Ni mixture were performed at various volume fractions and propagation distances of shock. The results of these simulations could be useful information to predict impact characteristics of mixtures.