ABSTRACT- CMS-0625512 The research objective is to synthesize and characterize carbon-based nanolayer and nanocomposite coatings that have high hardness and low-friction performance in dry and humid environments. The principal investigator and his coworkers will synthesize these coatings by magnetron sputtering, a well-established coating deposition technique. There is evidence from preliminary experiments to suggest that these goals may be achievable. For example, doping hydrogenated carbon films with 5 atomic percent sulfur gives coefficients of friction of less than 0.01 in dry and humid environments. The adsorption of water will be explored using temperature-programmed desorption and quartz crystal microbalance techniques. In this way, the role of sulfur in maintaining low friction of hydrogenated carbon films in humid conditions can be understood. Hard and low-friction coatings are important in improving energy efficiency of mechanical systems in cars and planes. Because of the inert nature of these coating surfaces, they are also strong candidates as tool coatings for dry machining, which reduces cost and eliminates the need for disposal of used lubricants. In addition to the involving graduate and undergraduate students in this research, the principal investigator and his coworkers plan to construct demonstration units to illustrate the importance of friction in affecting the efficiency of mechanical systems. These units will be used to augment lectures given by the principal investigator to regular classes, the local community and professional societies.
