Tribological performance of fatty acid modification of sol–gel TiO2 coating

In this paper, the coatings with friction-reducing properties were investigated using both sol–gel and self-assembling techniques. The thin film of TiO2 was firstly prepared on glass substrates via a sol–gel method, followed by calcinating at 480 °C. The films of fatty acid were then deposited on the TiO2 surface to obtain a dual-layer film. The contact angle measurement and FT IR spectroscopy were used to determine the wetting behavior and chemical structure of films, respectively. The friction-reducing behavior of films sliding against a steel ball was examined on a macro friction and wear tester. It is found that fatty acid is strongly adsorbed on sol–gel derived TiO2 surface. Good friction-reducing behavior is observed for the glass substrate after duplex surface-modification with TiO2 surface obtained by sol–gel method and top layer of fatty acid.

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