Fast energy release from reactive materials under shock compression

Metal-based reactive nanomaterials (RNMs) can produce two to three times more energy than conventional organic explosives, but the exothermic reactions, which ordinarily require diffusive mixing of separated fuel and oxidizer components, are too slow and do not generate enough gas to produce detonations. Here, we studied shock initiation of 4Al/Bi2O3 and 4Al/BiF3 RNMs produced by arrested reactive milling. Initiated by a 3 km/s impact, which approximates a powerful detonation, fast energy release produced 3200 K temperatures. In the fluoride, a rapid volume increase was also observed. The shock-induced energy release was orders of magnitude faster than when the RNM was heated. Although these RNM powders by themselves likely cannot produce detonations, our results suggest that used as additives in detonating systems, they might significantly boost the energy of chemical explosives.