Where and when are nanodiamonds formed under explosion?

摘要

The formation of nano-sized diamonds during the detonation of a TNT/RDX explosive with 50/50 composition was investigated experimentally in situ by means of small-angle X-ray scattering using synchrotron radiation with nanosecond time resolution. No nanodiamonds were observed immediately after the detonation front, as only the nucleation of nanodiamonds takes place at this moment. The increase in small-angle X-ray scattering which was observed during 2 us was the cause of the dynamic growth of nanodiamonds. The inclusion of a very thin shell around the explosive causes a significant increase in this time, because the kinetic of nanodiamonds growth was changed. In another set of experiments, the nanodiamonds were artificially introduced into different explosives before explosion. The nanodiamonds were not destroyed in RDX immediately after the detonation front, but burned in an oxidants with some delay. In TNT, the nanodiamonds were not destroyed at all.