The influence of morphology of Al powder on combustion performance of Al/KClO₄ composition

The morphology of aluminium powder has a great effect on the combustion performance of aluminized compositions. The thermal behavior and burning performance of Al/KClO₄ composition which containes different types of aluminium powder were investigated by a differential scanning calorimeter (DSC), and the thermal decomposition equations of crystal shape conversion, melting, interfacial liquid phase reaction, and gas phase oxidation reaction were concluded. The influence of morphology on combustion performance was studied from the aspect of decomposition temperature, combustion heat and rate, and the thermal decomposition mechanisms of compositions were concluded. The results shows that the dominant reaction of compositions was an interfacial oxidation reaction of atomic Al with molten KClO₄. The fundamental factor which influences the combustion performance of compositions, was the variation of surface binding energy: The surface binding energy decreases with the increase in specific surface area and defects, and the corresponding performances macroscopically appear as low thermal decomposition temperature, quickly burning rates and strong heat effect.