Lubwama M., McDonnell K.A., Kirabira J.B., Sebbit A., Sayers K., Dowling D., Corcoran B.
School of Mechanical and Manufacturing Engineering, Dublin City University, Dublin 9, Ireland; School of Mechanical and Materials Engineering, University College Dublin, Dublin 4, Ireland; Department of Mechanical Engineering, Dundalk Institute of Technology, Dundalk, Ireland; Department of Mechanical Engineering, Makerere University, P.O. Box 7062, Kampala, Uganda
Lubwama, M., School of Mechanical and Manufacturing Engineering, Dublin City University, Dublin 9, Ireland; McDonnell, K.A., School of Mechanical and Materials Engineering, University College Dublin, Dublin 4, Ireland; Kirabira, J.B., Department of Mechanical Engineering, Makerere University, P.O. Box 7062, Kampala, Uganda; Sebbit, A., Department of Mechanical Engineering, Makerere University, P.O. Box 7062, Kampala, Uganda; Sayers, K., Department of Mechanical Engineering, Dundalk Institute of Technology, Dundalk, Ireland; Dowling, D., School of Mechanical and Materials Engineering, University College Dublin, Dublin 4, Ireland; Corcoran, B., School of Mechanical and Manufacturing Engineering, Dublin City University, Dublin 9, Ireland
The characteristics and tribological performance of DLC and Si-DLC films with and without Si-C interlayers were studied in this paper. The films were deposited on nitrile rubber using a closed field unbalanced magnetron sputtering ion plating system. The film properties and characteristics were determined by scanning electron microscopy (SEM), hydrophobicity studies, Raman spectroscopy and tribological investigations. Tribological performance of these films was investigated using a pin-on-disc tribometer under applied loads of 1N and 5N under conditions of dry and wet sliding. The effect of immersing the films in water on tribological performance was also examined. The results show that the morphology of the films had a crack-like network. At a substrate bias of -30V, the coatings were characterised by a very dense non-columnar microstructure. The highest value of the ratio of intensities of the D and G peaks (I D/I G) was 1.2 for Si-DLC film with Si-C interlayer. The lowest value of 0.7 was observed for DLC film. The contact angle (CA) of water droplets showed that the films were hydrophobic. These results are interpreted in terms of hybridisation of carbon in these coatings. The tribological investigation showed a dependence on both the tribological condition under investigation and the atomic percentage of Si in the films. At 5N normal load the lowest wear depth was observed for DLC films. © 2012 Elsevier B.V.
Applied loads; Atomic percentage; Closed field unbalanced magnetron sputtering ion platings; Coefficient of frictions; Crack-like; Diamond-like carbon; DLC film; Dry and wet; Film properties; Hybridisation; Nitrile rubbers; Normal loads; Pin on disc tribometer; Substrate bias; Tribological conditions; Tribological performance; Water droplets; Wear depth; Carbon; Coatings; Composite films; Contact angle; Hydrophobicity; Ion implantation; Raman scattering; Raman spectroscopy; Scanning electron microscopy; Silicon; Tribology