Optimization of stir casting process parameters in the fabrication of aluminium based metal matrix composites

Abstract

As the need for lightweight constructions rises in everyday life, metal matrix composites (MMCs) made of aluminum are used in a range of fields, including sports equipment, automotive, aerospace, and defense. The stir casting technique is the most commonly used commercially in industries to fabricate aluminum-based metal matrix composites because that is the most straightforward and economical strategy. The responsiveness of the process parameters was optimized using the statistical and mathematical technique known as response surface methodology (RSM) in the production of aluminum metal matrix composites reinforced with TiB2. The process parameters like reinforcement (1.5%, 3.0% and 4.5%), melt temperature (750 °C, 775 °C and 800 °C) and stirring speed (500 rpm, 600 rpm and 700 rpm) were considered for optimization. The obtained data were analyzed using three level factorial designs in Minitab software version 19. The developed model was evaluated using analysis of variance (ANOVA). The mechanical properties and microstructure of the specimens were investigated. ASTM standards were used to test the mechanical characterization, which included Vickers micro hardness and tensile strength. The results showed that the composite had improved tensile strength and micro hardness (29% increase). Microstructure studies revealed the presence of black Mg2Si particles as well as Al-Mg-Si eutectic in an alpha aluminum matrix, as well as fine and small TiB2 particulates.