Influence of Multi-pass Friction Stir Processing on Microhardness and Wear Properties of AA2014/SiC–CNT Hybrid Surface Composites

Friction Stir Processing (FSP) is a well-established solid-state severe plastic deformation surface alteration procedure. Fabrication, processing, and synthesis of materials with just surface alterations are all parts of FSP. As a result, the metal's base characteristics are preserved, and the result is a surface composite. FSP has lately been popular for producing surface composites that improve the tribological, mechanical, and microstructural properties of certain metals. Alloys of aluminum are used widely due to their light weightiness and corrosion resistance. AA2014 is used in the aircraft and automotive industries for its good machinability properties and good strength-to-weight ratio. In the current experiment, FSP was employed to produce a surface composite of AA2014 by using hybrid nano-sized SiC–CNT reinforcement. The number of passes has an important impact in determining the qualities of the surface composite in FSP. This paper examines the effect of the number of passes while keeping rotational and traversal speeds constant during FSP. After the experiment, analysis was carried out for microhardness and tribological properties. One-, two-, and three-pass FSPs were used to process the AA2014. The properties of the base metal, one-pass, two-pass, and three-pass Friction Stir Processed (FSPed) specimens were studied and compared by performing the experiment three times. From the average results of conducted experiments, it can be deduced that by increasing the number of passes, the microstructure improves in addition to improved coefficient of friction (COF), microhardness, and wear resistance for prepared specimens.