Roch, T.T.RochWeihnacht, V.V.WeihnachtScheibe, H.-J.H.-J.ScheibeRoch, A.A.RochLasagni, A.F.A.F.Lasagni2022-03-042022-03-042013https://publica.fraunhofer.de/handle/publica/23170410.1016/j.diamond.2012.12.002In this work, the influence of surface topography and micro structural changes on the tribological properties of tetrahedral amorphous carbon coatings (ta-C) structured using a holographic technique the direct laser interference pattering (DLIP) is investigated. By utilizing a nanosecond pulsed UV-laser (wavelength 355 nm), both ablation and graphitization thresholds were determined as a function of the pulse number. Incubation effects for the ablation threshold (~ 205 mJ cm- 2) were found to be negligible. However, for the graphitization of the film thresholds varying from 47 to 74 mJ cm - 2 were observed depending on the number of laser pulses utilized (from 1 to 30) and thus obtaining an incubation factor of 1.13. Using two- and three-beam interference setups, dot- and line-like periodi c arrays were fabricated. The tribological performance of these patterns was investigated under reciprocating sliding with a ball on disk method under non-lubricated conditions showing that coefficient of friction can be reduced from ~ 0.089 (un-patterned) to ~ 0.055 patterned ta-C (~ 30% reduction). The results can be explained based on the reduction of surface contact area combined with high hardness as well as the good intrinsic tribological properties of the ta-C films.endiamond-like carbonlaser materiallaser modificationradiation induced effectstribology621671553journal article