Response and Safety Evaluation of high Explosives Under Low Velocity Impact: Testing and Modeling

The ignition of high explosives, under low impact velocity has been focused for decades. In these years, novel experimental methods with in-situ visualization techniques, have been developed to understand more details of impact-induced ignition. Further, new material constitutive models have been developed in different scale levels. Both the experiments and models provide new perspectives on deformation, fracture and hotspot formation of high explosives. This work reviews the impact response of high explosives in view of testing and modeling. Novel in-situ testing on microstructure evolution demonstrated the microcrack played an important role on ignition. The macro-microscopic materials constitutive models were applied in this field, gaining new insights on the relation between the microcrack evolution and ignition. Mesoscale models revealed the interaction of polymer binder and explosive crystals, and further showed the energy dissipation during the impact. By constructing new computation framework, heterogeneous microstructure was considered to induce the stochastic ignition. These models have been widely used in engineering safety evaluation.