Microstructure & Tribological Behavior of Hybrid Al 319 Metal Matrix Composite Reinforced with SIC & Graphe Nano Powder

Aluminum 319 (Al319) is a commonly used aluminum alloy due to its better corrosion resistance and improved mechanical properties which is suitable for aerospace and automotive applications. However, the wear resistance and mechanical strength of Al319 can be further improved by reinforcement with nanoparticles. To improve the benefits of these reinforcements, it is necessary to optimize the stir casting process for uniform particle dispersion and minimum errors. To address this challenge, this study focuses on the fabrication and analysis of Al319 composites reinforced with SiC and GNPs using the electromagnetic stir casting method. Six different composites (BM, MR1, MR2, HR1, HR2, and HR3) are fabricated using different weight percentages of SiC and GNPs. These composites are subjected to wear analysis, porosity, microstructural and scanning electron microscopy (SEM) analysis. The best performing composite is selected from the initial experiment for further optimization. The stir casting parameters are optimized using Response Surface Methodology (RSM) based on Full Central Composite Design (FCCD). The results showed that the addition of 17%wt SiC and 3%wt GNPs in Al319 alloy improves wear resistance. This composite achieved the lowest wear rate of 0.0112 mm³/m at 2400 m sliding distance and 20N load. The porosity analysis showed that the HR2 composite presented optimal balance and minimal porosity. The RSM-FCCD reveals that optimal 100 Hz stirring intensity for 12 min yields a higher tensile strength of 324.42 MPa and microhardness values of 135.81 HV. The study concludes that hybrid reinforcement of SiC and GNPs not only increases wear resistance but also maintains appropriate mechanical properties which suitable for automotive industry applications.