Particle Characteristics of Trace High Explosives: RDX and PETN

Published

October 16, 2008

Author(s)

Jennifer R. Verkouteren

Abstract

The sizes of explosives particles in fingerprint residues produced from C-4 and Semtex-1A were investigated with respect to a fragmentation model. Particles produced by crushing RDX and PETN were sized by using scanning electron microscopy combined with image analysis, and polarized light microscopy was used for imaging and identifying explosives particles in fingerprint residues. Crystals of RDX and PETN fragment in a manner that concentrates mass in the largest particles of the population, which is common for a fragmentation process. Based on the fingerprints studied, the particle size to target for improving mass detection in fingerprint residues by Ion Mobility Spectrometry (IMS) is 20 mm in diameter. Although the particles smaller than 20 mm in diameter have a higher frequency, they constitute less than 20% of the mass of the particle population. Efforts to improve collection efficiency of explosives particles for detection by IMS, or other techniques, must take into consideration that the mass may be concentrated in a relatively few particles that may not be homogeneously distributed over the fingerprint area. These results are based on plastic-bonded explosives such as C-4 that contain relatively large crystals of explosive, where fragmentation is the main process leading to the presence of particles in the fingerprint residues.

Citation

Journal of Forensic Sciences

Pub Type

Journals

Keywords

C-4, explosives, fingerprint, IMS, particle size, PETN, RDX, Semtex

Citation

Verkouteren, J. (2008), Particle Characteristics of Trace High Explosives: RDX and PETN, Journal of Forensic Sciences (Accessed May 5, 2024)