Research Regarding the Properties and Combustion Performance of a Thermal Decoy Pyrotechnic Composition

Abstract

The present research focuses on the characterisation of a new formulation for thermal decoy pyrotechnic composition, as an alternative to magnesium-teflon-viton (MTV) formulations. The oxidant used in the composition is potassium perchlorate, given its good thermal stability and high percentage of available oxygen. The fuel of choice is magnalium (alloy of Al-Mg 50-50 % wt.), as an higher energy alternative to magnesium. The binder used in the composition is a blend of solvent free polyurethane and a chlorinated rubber. The main advantages of this composition are related to the high thermal stability, the ease of processing, by squeeze casting method and its good combustion performance (temperature and burn rate profile). The use of chlorinated rubber in the composition is beneficial, as a sensible increase in the burn rate and combustion temperature is observed. The morphological properties and chemical composition of the material is evidenced by SEM-EDS analysis while the burn rate and combustion temperature is recorded with a high speed thermal camera. The combustion heat and specific volume is calculated with a dedicated thermochemical code while the results are validated in experimental determinations. The presented formulation can represent a more safe and cost effective material to be used in thermal countermeasure ammunitions.