Effect of Silicon Content on wear and Hardness of Al-Si Alloys

Abstract

In the current work the Al-Si composite is prepared using stir casting method with variation in the percentage(4%, 6% and 8%) of the Si particles in it. stir casting method is one of the cheapest method for production of Al alloys. The prepared composites of different percentages of Si are investigated for it wears behaviour using Pin-on-Disk machine and other properties like hardness. Characterization of Worn surface of the composite is done using SEM. Among the metallic matrices, the aluminum-based matrix remains the most studied metal matrix material for the production of MMCs. This is largely due to the large variety of properties provided by aluminum-based matrix composites at low manufacturing costs. While many Metal Matrix Composites ( MMCs) are desirable for use in various industrial applications, Aluminum Matrix Composites ( AMCs) are the most commonly used in specialized applications because they combine reasonable strength , low density, durability, machinability, availability , performance and price. In aerospace applications, the excellent tribological characteristics of Al-Si and Al-Sn alloys have led to their widespread use, especially in plain bearings, cylinder liners and internal combustion pistons. It is seen that Si is uniformly distributed in the Al matrix and hardness increases to 71BHN with 8%Si in Al matrix. Further analysis revealed that the microstructure homogeneity of the samples is strongly affected its hardness and Wear rate decreases with increase in Si.