| AVS 62nd International Symposium & Exhibition | |
| Nanometer-scale Science and Technology | Tuesday Sessions |
| Session NS+SP-TuM |
| Session: | Nanoscale Imaging and Materials Characterization |
| Presenter: | Rachel Huber, Los Alamos National Laboratory (LANL) |
| Authors: | R.C. Huber, Los Alamos National Laboratory (LANL) D. Podlesak, Los Alamos National Laboratory (LANL) M. Bagge-Hansen, Lawrence Livermore National Laboratory (LLNL) D. Dattelbaum, LANL M. Firestone, LANL T. Graber, Washington State University R. Gustavsen, LANL R. Hodgin, LLNL B.J. Jensen, LANL L.M. Lauderbach, LLNL P. Rigg, Washington State University B. Ringstrand, LANL S. Seifert, Argonne National Laboratory N. Sinclair, Washington State University E. Watkins, LANL T.M. Willey, LLNL T. van Buuren, LLNL |
| Correspondent: | Click to Email |
High explosive (HE) detonations drive chemical reactions under extreme conditions, in which explosive molecules are rapidly converted to small molecular products such as carbon, H2O, CO2 and N2. Solid carbon products are known to be comprised of several allotropes including amorphous carbon, graphite, onion-like graphitic carbon, fullerenes, and nanodiamonds (NDs). The formation of different allotropes arises from the temperatures and pressures conditions on the nanocarbon phase diagram accessed during the detonation. Previously, only the starting explosive samples, and post-mortem soot were available for structural analysis. However, a fundamental understanding of how carbon particles form and evolve during a detonation must occur in real-time on the nanosecond timescale. New developments in in-situ time-resolved small angle X-ray scattering (TR-SAXS) has allowed for the measurement of multiple SAXS spectra of detonating Composition B-3 (60% TNT, 40% RDX) at the Dynamic Compression Sector (Sector 35-B) at the Advanced Photon Source (Argonne National Laboratory). The TR-SAXS measurements coupled to the detonation on the ns-timescale are the first of their kind in the United States. Through Guinier and Porod analysis of the TR-SAXS data, we are able to determine the size, morphology, and phase of the carbon allotropes at time delays behind the detonation front.1,2 In addition, electron microscopy, X-ray photoelectron spectroscopy, and static SAXS were used to study the carbon solids in the post-detonation soot. By understanding the formation of solid carbon behind the detonation front, an improved theoretical framework may be applied to modeling the products equation of state for explosives.
1 Ten, K. A., Pruuel, E. R. & Titov, V. M. SAXS Measurement and Dynamics of Condensed Carbon Growth at Detonation of Condensed High Explosives. Fullerenes, Nanotubes and Carbon Nanostructures20, 587-593, doi:10.1080/1536383x.2012.656542 (2012).
2 Titov, V. M., Tolochko, B. P., Ten, K. A., Lukyanchikov, L. A. & Pruuel, E. R. Where and when are nanodiamonds formed under explosion? Diamond and Related Materials16, 2009-2013, doi:10.1016/j.diamond.2007.09.001 (2007).