Mechanism and characteristics of thermal action of HMX explosive mixture containing high-efficiency fuel

Abstract

In this study, the thermal stability and detonation properties of three types of explosives were investigated. Results indicated that nanoaluminum powder improved the detonation properties of HMX by increasing the specific surface area of HMX, which substantially increased the explosion heat and power. The decomposition temperatures of the three explosives containing aluminum hydride, ammonia borane, and nanoaluminum powder during slow cook-off at heating rates of 1.5 and 10°C min–1 were measured as 246°C and 241°C, 256°C and 261°C, and 238°C and 264°C, respectively. The explosives containing hydrogen storage materials swelled; however, the nanoaluminum powder was only slightly peeled off at the edge of the grains during cook-off. Differential scanning calorimetry (DSC) curves of the explosives containing hydrogen storage materials exhibited endothermic and exothermic peaks before the major exothermic reaction peak during the cook-off tests. In contrast, only one weak peak was observed in the DSC curve of the explosive containing nanoaluminum powder before the major exothermic reaction. In addition, the additives and adhesives catalyzed the slow cook-off decomposition, which caused the transformation of HMX crystals and accelerated the thermal decomposition reaction of HMX. The addition of high-density hydrogen storage materials to HMX resulted in detonation heats and explosion powers much greater than cure HMX. This improved performance was attributed to the hydrogen storage materials in the explosives participating in a secondary reaction in the reaction zone at the instant of the explosion, effectively realizing complementary lossless energy and thus greatly improving the explosive power of the explosives.