MESO-SCALE MODELING OF DAMAGE INITIATION AND PROPAGATION IN HETEROGENEOUS ENERGETIC MATERIALS AND ITS IMPACT ON SENSITIVITY

Energetic materials (EM) are widely used in defense and civilian applications in propulsion, explosive, and pyrotechnic applications. They are crucial to mission success and for safety and reliability of key national security and defense systems. EM are complex materials with mixtures of crystals, binders, and other additives that lead to complicated, heterogeneous microstructures. Under different temperatures and loading conditions, damage (cracks, pores) can accumulate in the microstructure. Damage in energetic material microstructures can result in off-design performance or even failure of devices critical to national security and safety. For EM-based systems to maintain robust performance over a wide envelope of operational conditions, microstructural damage must be predicted and its effect on energetic material sensitivity must be mitigated. This proposed project will combine careful experimentation and first-principles physics-based multi-scale modeling to establish load-structure-damage-performance (L-S-D-P) linkages for pressed and plastic-bonded energetic materials. Models that encapsulate L-S-D-P linkages for materials that simulate polymer-bonded explosives (PBXs) will be constructed using data derived from high-resolution simulations; experiments will provide material property inputs and validation data for the simulations. The model representation of L-S-D-P linkages planned in this work will be invaluable to designers and manufacturers of EMs to ensure robust performance over the range of damage levels expected under hypersonic and other challenging operational regimes.