拉伸加载下PBX炸药力学性能的分子动力学模拟

In this paper, molecular dynamics method is used to study the strain rate dependence of HMX-based polymer bonded explosive (PBX) interface under dynamic tension loading. Our results show that the tension strength and elastic modulus of PBX increase with the increasing of strain rate. The fracture of HMX-F2311 is dependent on the strain rate: the initial strain mainly appears on the binder F2311, a main crack perpendicular to the loading direction is formed at low strain rate, while the failure path distributes on the whole model under high strain rate; the fracture of PBX is due to the debonding of binder. With the increasing of strain rate, the potential energy of HMX-F2311 increases rapidly, and the van der Waals force interaction plays a crucial role in the evolution of potential energy under high strain rate. The simulation reveals the effect of strain rate on the interface microstructure, mechanical behavior and fracture mechanism of the HMX-F2311, providing opinions for the design, preparation and safety of PBX.