Consolidation of Nanocrystals of Detonation Nanodiamond under Thermobaric Sintering

Abstract

Abstract—The structural and physicomechanical properties of composite materials obtained by sintering detonation nanodiamonds under high pressures and temperatures (P = 5 GPa, T = 1200°C) have been investigated. There is a slight growth of diamond crystals after sintering from 4.5 to 5.2 nm. It is shown that the strength of the samples locally reaches 14 GPa. The high microhardness of the material is due to the consolidation of diamond nanocrystals into strong polycrystalline aggregates owing to the formation of covalent bonds between crystals under high pressure and temperature conditions.