Influence of stirrer blade design on stir casting of Al Mg Cu/12% SiC composite

Abstract

Aluminium metal matrix composites are generally produced employing stir casting technique. The effect of stirrer blade on stir casting of aluminium composite with 12 wt% SiC, 4 wt% magnesium and 2 wt% copper was observed. The composites were prepared with 6061 base metal using three different design of stirrer blade which created different vortex fluid flow while stirring. Due to high density of SiC particles, it tries to settle in lower part of the molten metal matrix. Hence change in vortex technique by stirrer design modification can have influence on the mechanical and microstructure behaviour of the composites. The aluminium SiC composite are evaluated by mechanical properties and microstructure analysis based on stirrer blade design used while stir casting. The change in blade stirrer shows variation in testing tensile strength and hardness. The optical microstructure and SEM images were observed to analyze the cast structure and reinforcement distribution in the composites. The SiC particles were appeared to distribute along the grain boundaries of the composite and also cast defects were observed. Composite prepared with alternate peddle blade produced best mechanical properties.