(688c) Effects of Various Solvents On Thermites

Developing thin film energetic materials using blade casting techniques has recently received attention for its advantages in deposition efficiency.  This technique requires powdered thermite reactants to be combined with a solvent. Introducing solvents into the deposition processes prompts new questions about the influence of the solvent on combustion behavior and specifically flame speed. The objective of this study was to examine the effects of hexane, isopropanol and acetone on magnesium (Mg) + manganese oxide (MnO₂) and aluminum (Al) + MnO₂ on flame speeds. The powders were loaded into tubes and ignited by a hot wire. The flame speeds analyzed by a high-speed diagnostics show that the solvent used during mixing has an adverse effect on the flame speed of the powders. Results suggest that when the solvent evaporates, its residue remains on the particles and limits flame speed. The powders were baked for twenty-four hours at a temperature of 70^oC to release solvent residue from the particles. The flame speeds of the baked powders were shown to increase significantly and powders mixed in isopropanol exhibited the highest increase.