Shock-induced reactions in metal nitride – Boron nanostructured composites

Abstract

Shock-induced reactions were investigated in boron (B) – metal nitride (MeN: Me=Ga, Zr, Cr) exothermic systems. All considered powder mixtures were initially mechanically treated in a high-energy ball-mill to fabricate B-MeN nanostructured composite particles, which were subsequently shock loaded using an explosive charge. The structures of these materials were analyzed by conventional and synchrotron X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy. It was discovered that shock-induced reactions in the GaN+B system resulted in the formation of the metastable wurtzitic form of boron nitride (w-BN). This directly implies that ultra-fast (0.5–5 μs) reactions took place under the high-pressure conditions of the shock wave.