Static synthesis of microdiamonds from a charge containing nanodiamonds

The effect of detonation nanodiamonds (DNDs) [5] on the graphite-diamond phase transition at high pressures and temperatures has been experimentally studied. It is established that adding DNDs to a graphite-based charge for the diamond synthesis provides for a $\sim$1.4 times higher conversion of graphite into diamond even at relatively low pressures (4.5–5.5 GPa) and temperatures (1250–1500$^\circ$C). DND additives also modify the size distribution of microcrystalline diamonds.