Can W-Se-C coatings be competitive to W-S-C ones?

Abstract

W-Se-C coatings were deposited by co-sputtering from WSe2 and C targets. Carbon content varied from 25 up to 70 at.%, Se/W ratio was between 0.9 and 1.0, with no significant influence of the carbon content on their variations. The hardness of the coatings was evaluated by nano-indentation with values between 3.8 and 5.6 GPa. The structure of the coatings analysed by X-ray diffraction in glancing mode could be defined as quasi-amorphous. The tribological properties were evaluated in an SRV machine using reciprocating ball-on-disk tests under increasing loads. In general, the friction gets decreased with increasing loads. The comparison with other transition metals, dichalcogenides alloyed with carbon, namely Mo-Se-C and W-S-C systems, showed that W-Se-C coatings could be a good alternative with almost identical friction properties. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.