Computational Design of Graded Density Impactors for Shock Loading

The method of 1D elastic plastic hydrodynamic calculations, the mixing model of different material constituents, and the shock dynamics code of compressible fluids were verified through the overall comparisons of the calculated results with the experimental data from Lawrence Livermore National Laboratory (LLNL). A Mg-W system prepared for graded density impactor (GDI) for quasi-isentropic compression was proposed by means of numerical simulations. By considering the actual material fabrication, the technical restrictions of minimum thickness of discrete layer, and the limitation of maximum mixing rate of the two individual constituents, a model GDI of a novel Mg-W system was designed to actualize the required loading traces and anchor the structural characteristics of GDI. Numerical calculations show that the loading path and intensity are highly sensitive to the distribution of wave impedance of GDI. The experimental designs and predictions for different complicated loading/unloading processes can be realized through model calculations.