Determination of elastic constants of energetic materials based on experimental data on mechanical impact

The article addresses the problem of developing a mathematical model for the numerical analysis of potential emergency situations involving energetic materials (EMs), which are highly sensitive to mechanical and thermal loads. The mathematical model and calculations are based on dynamic and thermodynamic material properties obtained from experiments involving mechanical impact by a metallic striker on an EM. This allows the use of an elastic-plastic homogeneous medium model to describe the deformation process of the EM. The article presents the problem formulation corresponding to experiments on striker impact on the EM and describes the system of continuum mechanics differential equations in Lagrangian variables. The Prandtl–Reuss model is used to simulate plastic flow, along with material state equations and boundary conditions accounting for the mechanical and thermal interaction between the striker and the EM. Based on experimental data from the impact of a metallic striker on an octogen-containing EM, numerical modeling of the elastic-plastic flow of the EM is performed, enabling the determination of the material's elastic constants. The calculated results on the dynamics of striker penetration into the EM have shown good agreement with experimental data, confirming the adequacy of the proposed mathematical model.