Formation Processes of Metal-Rich Tribofilm on the Counterface During Sliding Against Metal/Diamondlike-Carbon Nanocomposite Coatings

Formation processes of metal-rich tribofilm on the counterface during sliding against metal/diamondlike-carbon nanocomposite coatings have been investigate. The hybridization between DLC matrix and Cu or Ag provides good electric conductivity to solid lubricant films. Metal-rich tribofilms are formed on the counterface of both Cu-DLC and Ag-DLC during sliding, which is important factor to obtain excellent tribological performance as well as good electric conductivity. Such tribofilms are almost pure Cu and Ag. The origin of the tribofilm is the metal clusters in the Me-DLC, and the adhered Cu and Ag clusters on the counterfaces are possibly sintered and refined during iterative plastic deformation in the frictional interface which generates high pressure and high shear rate.