Underwater explosion energy output characteristics of hexanitrohexaazaisowurtzitane (CL-20)-based aluminized explosives with different aluminum powder particle sizes

Aluminum powder particle size (D₅₀) is quite important for how to improve the energy release level and formulation design of aluminized explosives. In this paper, four experimental samples of CL-20-based aluminized explosives with aluminum powder particle sizes including 2, 13, 24, and 43 μm were designed. The experiments were carried out through an underwater explosion tank and compared with explosives containing lithium fluoride of the same particle size. The results show that the burning of aluminum powder promoted the shock wave propagation and bubble expansion. Aluminized explosives have a lower and then higher decay rate than lithium fluoride-containing explosives. For the experimental range of aluminum powder particle sizes, with an increase in D₅₀, the peak shock wave pressure first increased and then decreased, reaching the maximum at 24 μm; the shock wave and loss energy gradually increased, while the bubble energy, energy utilization, and underwater explosion total energy all gradually decreased. To a certain degree, the energy output structure can be regulated by adjusting the D₅₀ under the premise of constant total energy of explosives. The experimental results improve our understanding of how D₅₀ affects the underwater explosion parameters of aluminized explosives, which is of great significance for improving their energy utilization.