RELATION OF FRICTION AND WEAR TO PROCESSING PARAMETERS OF POLYCRYSTALLINE DIAMOND FILMS GROWN ON SILICON AND SILICA SUBSTRATES BY THE HOT-FILAMENT METHOD
C. Lai et al., RELATION OF FRICTION AND WEAR TO PROCESSING PARAMETERS OF POLYCRYSTALLINE DIAMOND FILMS GROWN ON SILICON AND SILICA SUBSTRATES BY THE HOT-FILAMENT METHOD, Materials science & engineering. A, Structural materials: properties, microstructure and processing, 183(1-2), 1994, pp. 257-265
Polycrystalline diamond films were deposited on silicon and silica sub
strates in a hot filament chemical vapor deposition reactor using veno
us pretreatment times and methane gas concentrations. Friction and wea
r tests were performed with a pin-on-disc tribometer under 100 and 200
gf loads without lubrication in the ambient environment. Tests show t
hat friction coefficients decrease with both increasing load and numbe
r of traces, which was attributed to the formation of graphite during
wear. Wear tests indicate graphitization to be the primary wear mechan
ism, with occasional wear pits caused by grain pull-out. The formation
of wear pits is believed to be related to the presence of amorphous c
arbon in a very small fraction of the grain boundaries.