A SURFACE-ANALYTICAL STUDY OF TRIBODEFORMED ALUMINUM-ALLOY 319-10 VOL-PERCENT GRAPHITE PARTICLE COMPOSITE

In order to understand friction and wear processes of aluminum alloy-graphite composites, a basic understanding of tribochemical interactions between graphite particles, atmosphere and substrate must be developed. Our previous X-ray photoelectron spectroscopy (XPS) studies have revealed the species of carbon and the oxidation layer formed on the wear surface during sliding. In this study, Auger and XPS techniques were used to analyze the tribodeformed surface of the composite. It has been found that a thin lubricating film of carbon is formed during sliding wear with different thicknesses at different regions which tends to reduce the coefficient of friction. Many areas of the surface exhibit no discoloration from that typical of these aluminum alloys. Surface analysis of these regions within the range of the present test conditions detects a thin (50-100 Å) film apparently consisting of a mixture of graphite and other (primarily air deposited) carbonaceous species. Certain other regions exhibit dark spots, with XPS and Auger analysis, suggesting a relatively thick concentration of carbon in this region in the form of graphite particles. © 1990.