Abstract
The influence of topological features of sliding surfaces on the solid lubricant behaviors of carbon onions was examined. Friction coefficient and service life were measured by ball-on-disk type friction testing in vacuum using silicon disks with various fine patterns 3-50 nm in depth. Two types of carbon onions of which average particle diameters are 5 and 20 nm were prepared. As a result, lower friction coefficients and longer service lives were simultaneously observed on the disks with surface roughness similar to the particle size of carbon onions. The formation of carbon onion film several tens of nm thick was observed on sliding surfaces. This behavior was slightly more typical on the silicon disks with the pattern parallel to sliding direction, and was also observed in the friction tests using quartz glass disks.
