Tribological characterization of hard carbon films prepared by laser-arc

Hard diamond-like carbon films were deposited on silicon wafers and hardened steel substrates using the method of laser-induced, laser-pulsed and laser-guided vacuum arc evaporation (LASER-ARC). The deposition was carried out in a vacuum of approximate 10 high -4 Pa with an arc repetition frequency of 100 Hz, a peak current of 500 A and a pulse duration of approximate or equal 37 Mys. After substrate cleaning by an Ar+ - ion bombardment films were prepared at different deposition temperatures (50 degree C smaller than Ts smaller than 500 degree C) up to a thickness of approximate 0.5 Mym. The tribological behavior of as deposited C-films were studied by means of a vibration wear technique with a steel ball (AISI 52100) as a conterbody. To check the effect of water content of surrounding air test were performed in air of ambient temperature but varied relative humidity. From the in situ measurement of friction and wear the tribological life time of films were determined. From the wear s can at the end of a test and additional profilograms the wear of the ball and that of the disk were calculated separately. The results demonstrate that a very good wear resistance and a low coefficient of friction is found for special conditions of the coating process by Laser-Arc. However the friction and wear of all coatings was increasing strongly in dry air. These results are the basis of further investigation to modify the coating process by Laser-Arc