Microstructure Characterization and Mechanical Properties of Al-SiCp Composites

In recent years the aluminum matrix composites are gaining wide spread applications in automotive, aerospace, defense, sport and other industries. The reason for this is their exciting properties like high specific strength, stiffness, hardness, wear resistance, dimensional stability and designer flexibility. The present work reports on mechanical properties and microstructure analysis of Al-SiC particulate composites with different wt. % of SiCp. Al-SiCp composite specimens with different weight % of SiC (viz. 5, 10, 15, 20, 25 and 30 wt. % of SiC) were fabricated through casting process. The induction furnace and open furnace were used for melting of Al-SiC particulate composites. The induction furnace gives the advantage of self-stirring action on the introduction of SiC particles. Grinding and fine polishing was done using diamond paste to prepare different samples for microscopic study. The microstructure examination of the polished and carefully etched Al-SiCp composite specimens showed that the structure consists of a network of silicon particles, which were formed in inter-dendritic aluminum silicon eutectic composition. These SEM micrographs clearly indicate that the SiC particulates are dispersed uniformly in the Al matrix even at higher percentage such as 20 weight % SiCp. The SiC particulates were observed to be in irregular shape.