Friction and Wear Behavior of AA 7075-Si3N4 Composites Under Dry Conditions: Effect of Sliding Speed

In this paper, the effect of sliding speed on tribological properties of AA7075-Si3N4 composites has been investigated. The tribological testing was carried on a unidirectional pin on disc tribometer at three different sliding speeds (1 m/s, 4 m/s, and 7 m/s) at a constant load of 30 N. The wear loss increased with an increase in speed and coefficient of friction decreased with an increase in speed. The morphologies of the worn samples were investigated by SEM and it was observed that in case of unreinforced alloy and lower concentrations (2 wt% and 4 wt%) delamination was the dominant wear mechanism and, in case of higher Si(3)N(4)content (8 wt%) abrasive wear was the dominant wear mechanism. Heavy plastic deformation and deeper grooves were observed in case of higher speeds. Mechanically Mixed Layer (MML) formation was also confirmed by EDS. The developed material could serve various high speed sliding wear applications in automotive sector.