Plasma pressure compaction of nanodiamond

Increase of nanodiamond crystal size by selective oxidation

“…In addition, such treatments allow the control of the surface chemistry and reduce agglomeration [12,13]. However, there were only few attempts to control the average crystal size in ND powders [14,15]. Previous studies on oxidation of ND show the possibility of selective removal of smaller diamond crystals [16,17], illustrating a potential method for manufacturing nanodiamond with controlled crystal size.…”

Porous electrically conductive materials produced by Spark Plasma Sintering and hot pressing of nanodiamonds

“…At the same time, a possibility exists to consolidate nanodiamonds at relatively low ϯ pressures (several tens of MPa) in a compact of reasonable quality. Osswald et al [6] used Plasma Pressure Compaction of nanodiamonds at 65 MPa to produce porous compacts, in which excessive graphitization was prevented.…”

Liquid-phase sintering of nanodiamond composite coatings on aluminum A319 using a focused laser beam

“…The sintered ND pellets contained 50% porosity (density 1.3-1.6 g/cm 3 ) and some graphite. The best sintered ND sample, processed at 1173 K, possessed a hardness of 0.2 GPa and a Young's modulus of 5.5 GPa [25]. It has a structure consisting of graphite linking diamond particles into larger agglomerates.…”

“…It is limited to producing small samples and is not cost effective. Another technique for creating a ND sample is plasma pressure compaction where the ND powder is subjected to lower temperatures and pressures (973 K to 1473 K, 65 MPa) [25]. The sintered ND pellets contained 50% porosity (density 1.3-1.6 g/cm 3 ) and some graphite.…”