The effect of the particle surface and binder properties on the response of polymer bonded explosives at low impact velocities

Abstract

Polymer bonded explosives are designed to initiate under controlled conditions. However, accidental ignition leading to a deflagration, and even detonation, may occur during manufacturing, handling and transport. Understanding how ignition depends on microstructural features, such as cracks and voids in the particles, and on the adhesive and mechanical properties of the binder through predictive numerical simulations and modeling will help to improve safety. Finite element simulations and experiments of a single high energetic material particle embedded in polymer binders are performed to investigate the effect of the material properties of the binder and the particle surface properties, on damage and temperature at an impact velocity of 10 m/s. Particles with low and high quality surface properties, and two different binders are analyzed. The simulations with the lower stiffness binder do not show a significant increase in temperature after impact. A polymer with higher stiffness induces more particle damage under impact contributing to a larger temperature rise. Furthermore, high quality surface and higher adhesion strength induces larger stresses and increase the temperature rise.