Effect of Addition of Fine SiC Particles on the Dry Sliding Wear Behaviour of Extruded 2014 Al-Alloy

Composites of 2014 alloy made by dispersing 10 vol.% of fine (20–50？μm) SiC particles using vortex method ensuring uniform distribution of SiC particles in the matrix have shown uniform distribution of SiC particles. Mechanical properties of the composites have also registered an improvement over the alloy. In an attempt to further improve the properties, the composites were subjected to hot extrusion of cylindrical rods along with the alloys under similar experimental conditions. A temperature range of 300–350°C and an extrusion ratio of 10？:？1 were maintained during the process. The extruded samples were compared for their mechanical properties, and improvement was noted. The mechanism of material failure from fractographic studies showed difference in behaviour between the alloy and composite. Dry sliding wear studies carried out on extruded specimens exhibited improved wear behaviour in composites over alloys as measured by volume loss and wear rate. Wear mechanism was studied from the worn surface and correlated with the wear performance. It was observed that the presence of SiC particles reduces the tendency of delamination and thus material removal from the wear surface. 1. Introduction Worldwide, researchers have repeatedly demonstrated on a laboratory scale, attractive properties in aluminium-based metal matrix composites with SiC dispersoids. The property improvements relate to microstructural, mechanical properties such as specific modulus, strength, and wear resistance, in addition to a service temperature capability in selected aluminium-based composites with selected second phase dispersoids. It is an open knowledge for researchers in this field now as to the alloy systems, second phase’s nature, volume fraction, and fabrication routes that can exhibit improved performance. The properties attained are so attractive that these materials hold potential for applications in aerospace, automotive, electronic, sports, ballistic protection, and other general engineering fields [1–14]. However, the expectation to see the MMCs as engineering products would need their mass production and confidence in the ability to subject these materials to secondary processing while maintaining the improved properties attained in the cast condition. Open literature regarding mass production is seldom reported. Attempts at secondary processing of Al-based MMCs especially through extrusion to deform the materials into desired shapes and refine the microstructure are being reported substantially now [15–22]; the extruded MMCs exhibit uniform reinforced distribution,