Morphology control and thermo-mechanical response of HMX

To reveal the dynamic regulation mechanism of morphological characteristics on the thermo-mechanical coupling process, HMX explosive crystals in blocky, rod-like and plate-like HMX forms were prepared using an Easy Max 402 fully automatic reaction calorimetry system by precisely controlling the process parameters. The effects of solvent temperature, antisolvent temperature, stirring rate, peristaltic pump speed and crystal morphology-controlling agent on the morphology and particle size of HMX crystals were systematically investigated. The morphology, particle size distribution, and polymorph of HMX crystals were characterized, and the mechanical sensitivity of different crystal morphologies was systematically tested and analyzed under varying temperatures. At the same temperature, blocky HMX crystals with smaller aspect ratios and regular morphology show lower impact sensitivity, while plate-like crystals show lower friction sensitivity. The results show that with increasing temperature, the impact and friction sensitivities of HMX with different morphologies first decrease and then increase, and all morphologies exhibit high impact sensitivity at −10°C. The study found that shape and polymorph strongly affect the temperature dependence of HMX impact sensitivity, while polymorph dominates its friction sensitivity, providing theoretical guidance for safer HMX production, storage, and transport.