Abstract

Hybrid ceramic particulate reinforced A356 aluminium composites were prepared via the semi-solid stir casting process followed by hot rolling. Fine micron-sized SiC powders and large micron-sized Al2O3 particles were used. The particles were coated in order to increase the ceramic incorporation and bonding with the metal. The corrosion behaviour of the composites was investigated using potentiodynamic polarization measurements. The results indicated that nickel coating and particles agglomeration of the fine SiC particles led to an increase in the corrosion current density in Tafel polarization curves. It was concluded that the composite manufacturing route employed reduced the corrosion resistance of rolled A356 alloy.