Thermal Behavior and Non-Isothermal Kinetic Studies on Titanium Hydride–Fueled Binary Pyrotechnic Compositions

Abstract

This study describes thermochemical properties and ignition characteristics of pyrotechnic compositions consisting of TiH2 + KClO3, TiH2 + KClO4, and TiH2 + Ba(NO3)2, where titanium hydride is used as fuel and KClO3, KClO4, and Ba(NO3)2 act as oxidants. Differential thermal analysis (DTA) and thermogravimetry (TG) techniques have been employed to elucidate the reaction process of these pyrotechnic systems. TG/DTA analysis of pure titanium hydride indicates that this compound decomposes at 535 °C. By replacing KClO3 with KClO4 as oxidizer in a titanium hydride–fueled mixture, the sensitivity of the mixture decreases. A TiH2 + KClO3 pyrotechnic mixture has a fusion temperature around 358 °C and ignition temperature around 472 °C. A TiH2 + KClO4 pyrotechnic system decomposes at 541.5 °C. However, replacing KClO4 with Ba(NO3)2 in this mixture, increases the ignition temperature of the mixture by at least 30 °C to ∼ 570 °C, which is a safe temperature for preventing activation of the mixture by accidental factors such as static electricity. The apparent activation energy (E), ΔG#, ΔH#, and ΔS# of the combustion processes were obtained from the DSC experiments. Thermokinetic data shows that the relative reactivity of these mixtures decrease in the following order: TiH2 + KClO3 > TiH2 + KClO4 > TiH2 + Ba(NO3)2.