Detonation NanoDiamond Growth and Aggregation Kinetics during High Explosive Detonations

Detonation nanodiamond has many practical applications that rely on its small size. However, during a detonation synthesis, the diamonds can grow too big or aggregate together, requiring significant post processing. In this study, the hierarchical aggregate structure and size of the nanodiamond was investigated using time-resolved X-ray scattering, with an overall global time resolution in this geometry of +/-50 ns. These experiments were performed on different high explosives that condense different carbon allotropes. Our experiments on octol and comp B show that detonation nanodiamond not only forms but rapidly aggregates potentially in the reaction zone and as the detonation products pass through the theoretical Chapman-Jouguet plane and densifies slightly over the subsequent ~ 100 ns. While TATB does not normally produce detonation nanodiamond, an overdriven detonation geometry produced X-ray scattering characteristic of detonation nanodiamond, but ~30 % smaller than the nanodiamond produced with comp B and octol.