(544e) Ignition Sensitivity of Nanoenergetics Produced by Various Processing Methods

Nanoenergetic materials are a class of materials that have been of much interest for over ten years now. Variation in methods of synthesis and processing have allowed for these materials to be tailored to many different applications (e.g., percussion primers, electric matches, low energy ignition devices, etc.). These applications require wide ranges of reactive energy outputs, reaction rates, and ignition sensitivities. Appropriate characterization methods have been developed for mechanical impact, thermal, and electrostatic discharge sensitivities. This study presents an explanation of ignition delay times of Al-Fe2O3, Al-MoO3, and Al-Bi2O3 nanoenergetic mixtures during exposure to a laser pulse as a function of a sample density and laser power. It was shown that the porosity of the energetic material significantly affects the ignition delay time due to the dependence of thermal properties as the function of that parameter. The effect of porosity on ignition delay was also investigated using a mathematical modeling. The model verified that an increase in porosity significantly decreases ignition delay time due to a much lower thermal conductivity and heat capacity of the sample. Electrostatic discharge sensitivity of the nanoenergetic materials was also investigated. This study determined that individual particle size and its morphology (both fuel and oxidizer), degree of consolidation, and processing methods can all have a significant affect on the sensitivity of the nanoenergetic materials to ignition by ESD.