SIMULATIONS OF THE COMPACTION OF ENERGETIC POWDER MATERIALS

摘要

This article presents simulations of the compaction of powder energetic materials in different situations by using the implicit HI NIKE2D code and the explicit AUTODYN code. Powder materials such as pyrotechnic compositions and explosives, are often subjected to high stresses both during production and use. The ability to foresee the mechanical behaviour of these powders is important since it provides the ability to study, a) the deformation of surrounding metal parts during press loading, b) the stress situation in the powder when subjected to external forces caused by launching and, c) the propagation of pressure waves during impact, initiation and burning. The simulations use the M-O powder material model which describes the complex mechanical properties of powder energetic materials. The M-O granular model includes an equation of state to describe the density as a function of the pressure, as well as a strength model to describe the capabilities to sustain deviatoric stresses. The model also includes a failure and a heal criterion. A hot-spot model has been attached to the powder model. Simulations showing the hot-spots caused by compaction of the energetic powders are also presented. The simulations and the numerical calculations gave good agreement with experiments under very different compression conditions. They thus indicate that the mathematical model can be used as a tool for studying the stresses and temperatures in the energetic material both during production and use.