Impact of aluminum powder content on explosion fireball expansion and shock wave propagation in HMX-based aluminized explosives

This study aims to investigate the effects of different aluminum (Al) powder contents on the expansion process of the explosion fireball and the propagation characteristics of shock waves in 1,3,5,7-Tetranitro-1,3,5,7-tetrazocane (HMX)-based aluminized explosives. Four different formulations of HMX-based explosive samples were prepared and subjected to air-blast tests. The explosion fireball and shock wave propagation were recorded using a framing camera and high-speed photography. Image processing, geometric feature extraction, and curve fitting were performed. The results indicate that: at the same time, with the increase in aluminum powder content, the brightness, radius, and area of the fireball all increased. The afterburning effect of aluminum powder prolonged the fireball's duration. The fireball radius was fitted using the two-phase exponential association equation, with the fitting error within 5% compared to the measured experimental values. At the same time, the shock wave velocity was highest for the explosive formulation with 20% aluminum powder content. This study systematically reveals the impact of aluminum powder content on the fireball expansion and shock wave propagation processes, providing significant theoretical and experimental support for optimizing explosive formulations, improving detonation efficiency, and controlling shock wave characteristics.