Effects of Microstructural Properties on Chemical Energy Release and Initiation Processes of Energetic Materials
Technical Report,01 Oct 2015,30 Sep 2016
Air Force Research Laboratory, Munitions Directorate Eglin AFB United States
Pagination or Media Count:
DoD energetic systems vary in complexity and microstructural heterogeneity from the detonator to the main fill. Research has shown that these heterogeneities influence the initiation behavior of our systems, thereby dictating performance and reliability however, only general trends have been established. A case in point is the established trend, whereby reduction of RDX particle size decreases the shock sensitivity of formulations being developed to meet Insensitive Munitions IM requirements. While these trends are used for formulation guidance, a lack of fundamental understanding of the initiation behavior has hindered our ability to satisfy IM requirements. More broadly, the DoD suffers from a poor foundational understanding of the underlying mechanisms that lead to energy localization and the formation of hot spots see below. This issue manifests as a degraded ability to effectively quantify the safety and reliability of ordnance devices. Furthermore, it handicaps our ability to develop precise specifications for explosive formulations, despite our best efforts utilizing parametric experimental studies as done during the development of a new penetrator formulation. We seek to establish a basic understanding of which microstructural features correlate with the sensitivity and performance of energetic materials, and ifhow these structures influence the chemical energy release reaction kinetics. This foundational knowledge will enable the quantification of performance and reliability, identify microstructural features influencing initiation behavior, establish microstructural standards by which material sets are tuned for specific purposes, generate novel data to improve the predictive capabilities of reactive flow models, and guide the future improvement of energetic materials formulations.
- Ammunition and Explosives