Optimisation of friction stir processing parameters to fabricate AA6063/SiC surface composites using Taguchi technique

Fabrication of metal matrix surface composites is an emerging trend of friction stir processing (FSP) applications. This research proposes fabrication of AA 6063/SiC surface composites (SCs) using FSP. Influences of FSP process parameters viz. tool rotational speed, traverse speed and tilt angle were investigated on the distribution of reinforcement particles and mechanical properties of SCs. Experiments were designed using Taguchi technique. Optimum combinations of process parameters were determined for higher microhardness and ultimate tensile strength respectively using signal/noise ratio graphs, response tables and analysis of variance method. Results revealed that the uniform dispersion of reinforcement particles and appreciable improvement in mechanical properties was achieved by employing optimal combinations of 1,400 rpm tool rotational speed, 40 mm/min traverse speed and 2.5° tilt angle. About 46% enhancement in microhardness was achieved with optimal parameters as compared to base metal. Conclusions of this research clearly correlate microstructural observations with mechanical properties and reinforcement distribution.