1999/06/01 by V. V. Brazhkin, В. В. Бражкин, A. G. Lyapin +8
Chemistry · Materials Science · #Fullerene Chemistry and Applications #Diamond and Carbon-based Materials Research #Carbon Nanotubes in Composites
paper · doi:10.1134/1.568104
The results of an investigation of the transformation of C 60 fullerite to diamond under pressure through intermediate three-dimensionally polymerized and amorphous phases are reported. It is found that treatment of fullerite C 60 at pressures 12–14 GPa and temperatures ∼1400°C produces a nanocrystalline graphite-diamond composite with a concentration of the diamond component exceeding 50%. At lower temperatures (700–1200°C) nanocomposites consisting of diamondlike ( sp 3 ) and graphitic ( sp 2 ) amorphous phases are formed. The nanocomposites obtained have extremely high mechanical characteristics: hardness comparable to that of best diamond single crystals and fracture resistance two times greater than that of diamond. Mechanisms leading to the transformation of C 60 fullerite into diamond-based nanocomposites and the reasons for the high mechanical characteristics of these nanocomposites are discussed.