Effect of Al–Mg–Mn Alloy on the Ignition Performance of RDX, HMX and CL-20

Abstract

Aluminized explosives are known as non-ideal explosives due to their incomplete energy release. In order to improve its energy release, Al–Mg–Mn was used to replace aluminum. In this article, Thermogravimetric (TG) and Differential scanning calorimetry (DSC) techniques were used to study the ignition performance of three explosives (RDX, HMX and CL-20) with different mass fractions (0%, 10 wt.%, 20 wt.%, 30 wt.%) of Al–Mg–Mn alloy powder. The results were compared with those of the formulations with the addition of aluminum. The results suggested that the effect of the addition of Al–Mg–Mn on the extrapolated ignition temperature and exothermic peak temperature of the ignition reaction of aluminized explosives is basically similar to that of Al. However, the addition of Al–Mg–Mn increased the exothermic enthalpy. Explosives with the addition of Al–Mg–Mn alloy powder could release 1.7–17.4% more energy, depending on the mass fraction. On the other hand, unlike aluminum which reacts only during the ignition of CL-20, Al–Mg–Mn was involved in the exothermic reaction of all three explosives. During the exothermic decomposition of explosives, the more active magnesium in Al–Mg–Mn will be oxidized, and magnesium vapor will overflow along the grooves and crevices on the surface of the particles, thus destroying the surface oxidation shell and prompting the active ingredients inside to participate in the reaction.