Effect of friction stir processing parameters on mechanical properties of Al8011/CeO2/SiC/RHA metal matrix composite

In this research work, the FSP route opted to fabricate the metal matrix composite (MMC) on the surface of an aluminium 8011 alloy sheet by incorporating different volumetric compositions of silicon carbide (SiC) and cerium oxide (CeO2) with a constant 5% volumetric composition of rice husk ash (RHA). The fabrication process was based on the L27 design of experiments. Taguchi-coupled grey relational analysis (GRA) was employed for process optimisation with four factors: tool rotation speed, tool travel speed, reinforcement volume, and tool type, each with three levels, while tensile strength and micro-hardness were taken as the response variables. The optimal parameter setting for fabrication of Al8011 MMC was 600 RPM of rotational speed (level 3), 20 mm/min travel speed (level 1), reinforcing volume% (level 2), and straight cylinder pin profile (level 1). The corresponding values of the optimised response variables were 181.91 MPa tensile strength and 139.09 Hv microhardness. The tensile strength and microhardness of base Al8011 were found to be 175.77 MPa and 92.72 Hv, respectively. Meanwhile, the microstructure of the optimal FSP-processed MMC was analyzed through the scanning electron microscopy (SEM) technique, which confirmed a homogeneous distribution of reinforcing agents and refined grain structure.