Effect of different additives on the thermal properties and combustion characteristics of pyrotechnic mixtures containing the KClO4/Mg–Al alloy

The thermal properties and combustion characteristics of KClO4/Mg–50%Al, KClO4/Mg–50%Al with additives such as nitrocellulose (NC), urotropine and guanidine nitrate (GN) were studied experimentally using differential thermal analysis (DTA) and thermogravimetry (TG) and closed bomb experiments. The results of DTA–TG analysis revealed that additives could affect thermal stability and the decomposition temperature of KClO4/Mg–50%Al alloy. The order of the ignition temperatures of mixtures (Ti) is KP/Mg–50%Al/urotropine (2#, 557.7 °C) > KP/Mg–50%Al/GN(3#, 553.6 °C) > KP/Mg–50%Al (1#, 538.8 °C) > KP/Mg–50%Al/NC (4#, 536.5 °C). On the other hand, the results of the closed bomb experiments confirm that the combustion pressures were all increased with the addition of additives. The ignition delay times of these mixtures are in the order KClO4/Mg–50%Al (1#) > KClO4/Mg–50%Al/GN (3#) > KClO4/Mg 50%Al/NC (4#) > KClO4/Mg–50%Al/urotropine (2#).