Effect of SiC on Mechanical, Microstructure and Tribological properties of Aluminum MMC processed by Stir Casting

Abstract

Stir casting process is an effective manufacturing technique for producing metal matrix composites. The extensively use reinforcing materials for the aluminum matrix composites are silicon carbide, aluminum oxide and graphite in the variety of particles. In this work, the effect of addition of SiC reinforcement on the microstructure, mechanical and wear properties of the Al5083-SiC MMCs has been studied. Aluminum matrix composite has been prepared by adding 3, 5 and 7 wt. % SiC through Stir casting process. The wear tests have been conducted using a pin on disc configuration under normal loads of 10, 20 & 30 N. The tribological behaviour was evaluated at a sliding velocity of 3.14 m/s and distance of 942 m. After the wear tests, the worn out surface of test specimens have been observed with Olympus inverted optical microscope to analyse the wear mechanisms. Microhardness tests were employed to measure the microhardness number (VHN) of Al 5083-SiC MMCs by indenting the diamond indenter. The tensile tests were conducted on universal testing machine to know the improvements in the strength. Microstructures are observed by using SEM and XRD analysis.The Tribological properties are superior with the increasing of addition of SiC particles to the aluminum matrix. The images of scanning electron microscopy shows a uniform distribution of SiC particles in the aluminium metal matrix.