Tribological properties of Al 7075 alloy and Al 7075 metal matrix composite reinforced with SiC, sliding under dry, oil lubricated, and inert gas environments

Abstract

Tribological properties of silicon carbide-based aluminum metal matrix composite and aluminum matrix alloy have been studied for various sliding speeds of 3.14 and 3.77 m/s and load range from 10 to 30 N under dry, lubricated, and inert gas (argon) environment. Pin-on-disk tribometer were used for experiments. The composite was fabricated by stir casting route by using aluminum 7075 alloy as the matrix and 10% by weight silicon carbide as reinforced material. Results have revealed that the value of coefficient of friction is found to be maximum in case of inert condition in matrix alloy at sliding speed 3.77 m/s and minimum in case of lubricated condition in composite at sliding speed 3.14 m/s. The wear rate is least for both the alloy and the composite under lubricated condition compared with dry and inert condition. Wear rate increases with the normal load and sliding speed and it is maximum in inert condition of matrix alloy at 30 N. Uniform distribution of silicon carbide in aluminum matrix alloy reduces the values of coefficient of friction and wear rate for composites compared to aluminum matrix alloy under dry, lubricated, and inert condition which increases the life of the composites for longer duration. Silicon carbide significantly improves the strength the aluminum matrix alloy in dry, lubricated, and inert condition and acts as load-bearing members.