In this paper, the tribological assessment of highly hydrogenated DLC coatings (～50 at % hydrogen) is reported. The coatings are deposited by means of a high-density Inductively Coupled Plasma (ICP) source. ICP plasmas combine the advantage of a high throughput (due to high plasma density) with low, controllable ion impact energies on the substrate. The tribological performance of the developed coatings has been assessed by ball-on-disc tests in different atmospheres (air 50% RH, vacuum and dry nitrogen). In dry and inert environments, the highly hydrogenated DLC coatings reach a very low friction level (0.02-0.03 in dry N_2, 0.006-0.013 in vacuum). In humid air conditions, the friction coefficient is increased to 0.2-0.3, showing a less stable level. With regard to wear rates, a very low wear factor could be obtained in dry N_2 (range E-017 m~3/Nm), whereas the highest wear factor was observed in vacuum (range E-015 m~3/Nm).
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