Study of the wear and friction behavior of immiscible as cast - Al - Sn / Graphite composite

In this paper we investigate the tribological properties of AlSn-based alloy with different amount of graphite at different normal loads and sliding speed. A modified impeller mixing coupled with chill casting technique was used for the preparation of immiscible alloys. In this paper Al-Sn binary alloys was chosen for this study. This binary system shows the miscibility gap at different concentration and temperature. Graphite was chosen as reinforcing element which was reinforced in the Al-Sn matrix. The graphite content in the composite varied from 1.6 to 8.4 wt%. The presence of graphite in the matrix not only improves the mechanical properties but also improve the tribological properties due to lubricating action. The ductility of composite materials showed the adverse effect with increase of the graphite content in the matrix. Pin-on-disc sliding wear tests were conducted in an ambient condition to examine the tribological behavior of the aluminum-based graphite composite. The experiment was commenced at different sliding distance, speed and using normal load. Having finished the tests, the weight losses of the specimen were measured, wear and friction characteristics were calculated with respect to time, depth of wear track, sliding speed and bearing load. Friction coefficient and wear volume have shown large sensitivity to the applied normal load and the testing time (or sliding distance). The XRD and SEM analysis were used to analyze the wear debris and track.