Thermal behavior of Al/Zr/KClO4 pyrotechnic compositions at high temperature

A pyrotechnic composition of aluminum, zirconium, and potassium perchlorate was prepared to obtain suitable safety and sensitivity. The thermal behavior, microstructure, and composition of the pyrotechnic compositions heated from 300 °C to 600 °C were investigated using differential scanning calorimetry (DSC), thermogravimetry (TG), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) to evaluate the properties of the pyrotechnics after the high-temperature process, such as the 1 A/1 W no-fire test. When the heating temperature increased, the sharp exothermic peak near 530 °C decreased, corresponding to the reaction of metal powders with potassium perchlorate. Gradual oxidizing reaction between Zr and KClO4 can occur in solid stage when the temperature exceeds 400 °C. With the increase of the heating temperature from 400 °C to 600 °C, the mass losses in TG curves decreased, and melted particles of KClO4 appeared gradually. The Al/Zr/KClO4 pyrotechnic composition was safe in the of 1 A/1 W no-fire test. Hence, Al/Zr/KClO4 can be used in flash pyrotechnics, fireworks, and fuel-rich propellants.