Abstract: Using distilled water and air as lubricants, the wear tests of ceramic-cast iron pairs are carried out on a M-200 type ring-block wear tester. For comparison, the ceramic-carbon steel pairs are also tested under the same conditions. The worn surface of specimens are observed under scanning electron microscope and optical microscope. Furthermore, the tribofilms are analyzed by using Auger electron spectroscopy (AES), energy-dispersive X-ray spectroscopy (EDAX) and image analysis technique. In the wear test of Si3 N4-cast iron pairs lubricated with distilled water, the friction coefficients of the pairs are just 0.02，and the wear rates of ceramic and iron are near zero. The reason why such superior tribological characteristics can be caused is that a tribochemical film, which has nough thickness and area, is formed on the wearing surfaces. However, in the test of Si3N4-carbon steel pair lubricated with distilled water, the friction coefficient is still high because the tribochemical film formed on the wearing surface is too thin and too small. A metal transfer film is formed on the ceramic surface when the ferrous metals slide against the Al2O3. In this situation, the wear amount of Al2O3 is quite small, but the wear amount of metals is large and the friction coefficient is rather high.

Key words: Cast iron, Ceramic, Tribofilm Friction and wear