HIGH TEMPERATURE DRY SLIDING WEAR BEHAVIOUR OF AL-SI/GRAPHITE COMPOSITES PROCESSED BY STIR CASTING

Aluminum alloy composites are extensively used for tribological applications due to excellent wear resistance especially during sliding under different operating conditions such as dry, wet and high temperature environments. In this present study, dry sliding wear behavior of aluminum silicon alloy reinforced with graphite (3 wt.%) was investigated by using Pin on Disc wear tester with different temperatures up to 350 degrees C in air. The wear rate of alloy and composite was decreased with increasing temperature due to oxide and glazing layers formation. However, the wear behaviour of composites were superior than that of alloy for all temperature conditions due to formation of rich tribo film between sliding surfaces by smeared graphite particulates. The alloy could sustain only up to 300 degrees C during sliding, but the composite could prolong till 350 degrees C. The worn surfaces of alloy and composites were characterized by scanning electron microscope to understand the wear mechanism.