Shock Initiation Characteristics of CL-20-Based Cast Cured Explosives with High Aluminum and Ammonium Perchlorate Contents

The addition of a large amount of aluminum and ammonium perchlorate will change the sensitivity of the explosive. At present, there is lack of deep understanding of the shock initiation characteristics of CL-20 based mixed explosives with high aluminum and AP contents, which is important for the optimization of the explosive components and safety use. In this paper, the electromagnetic particle velocity gauges were embedded in the wedge-shaped explosive to measure the particle velocity during shock initiation, and then numerical simulation model was constructed, based on the experimental data, the parameters of reaction rate model and equation of state were calibrated. By combining experiments and numerical simulations, the shock initiation characteristics and effects of aluminum and ammonium perchlorate contents on the initiation process were investigated. Results show that the two kinds CL-20-based cast cured explosives with high aluminum and AP contents are more sensitive than PBXW-115. The change of aluminum and ammonium perchlorate significantly changed the shock initiation behavior, which could lead to intersection point in the Pop relationship. Based on the characteristics of shock initiation, it can be inferred that the shock initiation process of explosives follows different mechanisms under low and high pressure. Under relatively low pressure, the shock initiation process of explosives is mainly dominated by the formation and growth of "hotspots", while under higher pressure, the rapid reaction of CL-20 itself will dominate the initiation and rapid growth of detonation.