From boundary to thin film lubrication under water: Influence of surface hydrophilicity on adsorbed water layer

The influence of surface hydrophilicity on adsorbed water layer was investigated using a thin film interferometry and a microtribometer based on laser interferometers. Experimental results indicate that, in the mixed film lubrication from the boundary lubrication to the thin film lubrication, the hydrophilic surface promotes the forming of thinner water film and the higher friction. It is thought that a layer of water adjacent to the surface forms an ordered water layer whose characteristic determines the properties of adsorbed water layer in the contact area. (C) 2010 American Institute of Physics. [doi:10.1063/1.3429074]