Effects of oxidizer on the secondary reaction of aluminum and metal acceleration for CL-20-based aluminized explosive

The addition of oxidizing agents in the explosives could enhance the burning rate and the reaction degree of aluminum powder due to the increase of oxidizing gas content in the detonation products. Therefore, it affects the metal acceleration ability of the explosive. The current study is concerned with investigating the metal acceleration ability of the CL-20-based aluminized explosive containing oxidizer affecting metal shells through standard cylinder tests. The diameter of the cylinder is 50 mm. An all-fiber displacement interferometer system with a photon Doppler velocimeter took into account the continuous measuring of the cylinder wall velocity over time. The detonation velocity was calculated by the velocity jump time interval of the cylinder wall. BKW equation was applied to calculate the detonation pressure. The effects of oxidizer on the ignition time and the reaction degree of aluminum powder were analyzed by replacing aluminum powder with lithium fluoride for comparison. According to the cylinder wall velocity energy source, empirical formula about explosive composition and the cylinder wall kinetic energy was fitted. The results show that CL-20-based aluminized explosive detonation velocity and aluminum content is linearly correlated, and oxidizer-containing explosives detonation velocity can be equivalent to oxidizer-free explosives within a certain margin of error. With the addition of oxidizer, detonation pressure, and the base explosive content no longer show the same increasing and decreasing relationship. When the aluminum content is 5% and 30%, the ignition time of aluminum powder is 4.81μs and 1.66μs earlier respectively. When the aluminum content is 5%, the reaction degree of aluminum powder reaches 1. The aluminum powder reaction rate for oxidizer-containing explosives and oxidizer-free explosives is mutually fast and slow. When the aluminum content is 30%, aluminum powder reaction degree and aluminum powder reaction rate for oxidizer-containing explosives are higher than that of oxidizer-free explosives throughout. Based on the fitted relationship equation, it is predicted that the maximum value of kinetic energy of the cylinder wall is obtained at 10% aluminum powder content with 10% oxidizer.