Dynamic fracture and frictional heating due to periodic excitation in energetic materials

摘要

Mechanical stimulus may lead to localized temperature increase due to the concentration of energy dissipation at microstructural features. Mechanically induced heating occurs, for example, when materials are subjected to periodic excitation. This is a particular concern in energetic materials where ignition may start a deflagration. In this study, finite element simulations are performed on a single beta-HMX particle in a polymer matrix subjected to mechanical periodic excitation. Different initial defects, such as cracks and interface debonding, are included to control the location of hot-spots nucleation. The model accounts for damage evolution and heat generation due to friction at cracks. The results indicate that hot-spots nucleate preferentially at the particle/binder interface, and therefore, the temperature rate is higher when the particle is initially debonded than when it is perfectly attached to the polymer. Published by AIP Publishing.