Shock response of nano-diamonds explored by dynamic x-ray diffraction shock compression

We have investigated the shock response of detonation nano-diamonds under dynamic conditions using the Dynamic Compression Sector of the Advance Photon Source for the purposes of understanding the potential fracture mechanism of nano-diamonds and to identify potential avenues for structural energy release. Commercial detonation nano-diamonds exhibit a compressed core, expanded shell that has been proposed to be a potential source for structural bond energy release under a fracture condition. Dynamic diffraction images from two-stage light gas gun experiments to 5.3 km/s were collected on compressed samples of nano-diamonds and Viton fluoropolymer binder mixture in various shock states. Powder diffraction data is refined to extract out core/shell changes with shock loading and show a bimodal response where the shell signal decreases with shock loading while the core signal shows a non-fractured response. These points to a partial fracturing of the nano-diamond particle without accompanying energy release from the core.