Metal-Element Compounds of Titanium, Zirconium, and Hafnium as Pyrotechnic Fuels

Conventional high-energy pyrotechnic fuels are typically metals, metalloids, or alloys. The use of inorganic compounds including ceramic materials in this role has been far less common. Following the development of boron carbide-based pyrotechnics in our laboratories, we have started to explore the pyrotechnic properties of other inorganic compounds, particularly those of titanium, zirconium, and hafnium. The transition metals of group 4 are well known as potent pyrotechnic fuels. However, metal powders are susceptible to aging and pyrotechnic compositions containing them can be sensitive to unintended ignition by electrostatic discharge. The use of the corresponding metal-element compounds may ameliorate these problems. Commercially available group 4 compounds containing hydrogen, boron, carbon, nitrogen, silicon, and phosphorus were obtained for an initial survey. The as-received materials were characterized by XRD, XRF, and SEM. Binary compositions containing these fuels and KNO3 or Bi2O3 were prepared and tested. The experimental results were compared with the output from FactSage thermochemical software. Diverse observed and predicted behavior suggests that these compounds may be useful for a variety of pyrotechnic applications.