Synthesis and Tribological Properties of Diamond-Like-Carbon Coatings on EVM Substrate

The surfaces of EVM,a dynamic sealing rubber,were modified with diamond-like-carbon(DLC) coatings synthesized in the glow discharge plasma deposition reactor equipped with pulsed carbon ion source.The original work was that the EVM substrate was pre-irradiated with ultrasonic wave.The influence of the ultrasonic irradiation temperature and time on the microstructures,phase-structures and tribological behavior of the DLC coating was investigated with scanning electron microscopy,Raman spectroscopy and conventional mechanical probes.The preliminary results show that the ultrasonic irradiation had a major impact.For instance,the DLC coating,comprising a fairly high content of graphite-phase,considerably increased the hardness and decreased the friction coefficient; and as the irradiation temperature and time increased,the friction coefficient of the increasing compact DLC coatings changed in a decrease-increase mode,accompanied by a significantly decreasing wear-rate.