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The present investigation deals with development of AA2219 composites with different weight fractions of Cerium oxide (CeO2) reinforcement and characterizing the microstructure and mechanical properties thereof. XRD and SEM micrograph confirm the presence of CeO2 particles and Al2Cu precipitate. The grain size of 0, 0.5, 1.0, 1.5 and 2 wt% CeO2 composites are 483, 453, 411, 362 and 328 μm, respectively. Addition of CeO2 significantly reduces the dendritic morphology and refines the α-Al grain structure. 2 wt% CeO2 addition has yielded the maximum hardness of 124 HV and yield strength of 87 MPa in all the composites developed. Additionally, the developed composites were evaluated by examining the wear characteristics with the co-efficient of friction (COF) and the specific wear rate. In this study, Taguchi's L25 orthogonal array was used to optimize the parameters like reinforcement fraction, load and sliding distance. Signal-to-noise ratio (S/N ratio) and analysis of variance (ANOVA) are used to obtain the parameters highly influencing the wear behaviour. Adhesive wear is exhibited by ploughing at lower loads and delamination is observed with increasing load. Deep shallow ploughs with embarked abrasion are observed at higher loads.

Statistical tools have shown to be very useful in the optimization of processes such as welding. Optimization is understood as the determination of the welding combinations that will lead to the maximization of a desired property, such as strength. This work proposes a statistical methodology to determine the optimum combination of welding parameters of FSSW in 6060-T5 aluminium alloy. Two Design of Experiment (DOE) statistical tools, Taguchi and Full Factorial Design (FFD) were used to determine the optimum combination of three welding parameters: rotational speed, plunge rate and dwell time. Four samples were produced for each welding combination and then subjected to shear test to evaluate joint strength. Quadratic regression was used to obtain an equation correlating joint strength and welding parameters. With the methodology presented, it was obtained an equation to correlate welding parameters and joint strength with acceptable accuracy. The results have shown that a proper combination of DoE tools like Taguchi and FFD is key to determining the optimum set of welding parameters in the FSSW process.