Comparison of Post-detonation Combustion in Explosives Incorporating Aluminum Nanoparticles: Influence of the Passivation Layer (Postprint)
Abstract
Aluminum nanoparticles and explosive formulations that incorporate them have been a subject of ongoing interest due to the potential of aluminum particles to dramatically increase energy content relative to conventional organic explosives. We have used time-resolved atomic and molecular emission spectroscopy to monitor the combustion of aluminum nanoparticles within the overall chemical dynamics of post-detonation fireballs. We have studied the energy release dynamics of hexahydro-1,3,5-trinitro- 1,3,5-triazine (RDX) charges incorporating three types of aluminum nanoparticles: commercial oxide-passivated nanoparticles, oleic acid-capped aluminum nanoparticles (AlOA), and nanoparticles in which the oxide shell of the particle has been functionalized with an acrylic monomer and copolymerized into a fluorinated acrylic matrix (AlFA). The results indicate that the commercial nanoparticles and the AlFA nanoparticles are oxidized at a similar rate, while the AlOA nanoparticles combust more quickly. This is most likely due to the fact that the commercial nano-Al and the AlFA particles are both oxide-passivated, while the AlOA particles are protected by an organic shell that is more easily compromised than an oxide layer. The peak fireball temperatures for RDX charges containing 20 wt. % of commercial nano-Al, AlFA, or AlOA were ~3900 K, ~3400 K, and ~4500 K, respectively.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 31, 2013
- Accession Number
- ADA622821
Entities
People
- C. A. Crouse
- C. E. Bunker
- C. G. Rumchik
- E. A. Guliants
- J. E. Spowart
- K. A. Fernando
- Michael J. Smith
- W. K. Lewis
Organizations
- Air Force Research Laboratory