Erosion-corrosion behaviour of aluminum alloy 6063 hybrid composite

Aluminum alloy 6063 (AA6063) composite with varying proportion of snail-shell-ash (SSA) and silicon carbide (SiC) reinforcement has been developed by stir-casting. Hardness and erosion-corrosion characteristics of the composite were studied. Erosion-corrosion behaviour of the composite was studied in a mono-ethylene glycol (MEG)-water environment with 20% v/v of ethylene glycol and 0.1 g/L silica sand particles using a re-designed miniature submerged impinging jet rig. SEM-EDX of the as-cast composites showed the presence of the particulates distributed in the matrix. The hardness of the aluminum alloy was enhanced up to a maximum value (with the addition of 7.5 wt % SiC+7.5 wt % SSA). However, hardness values declined when (10 wt % SSA+10 wt % SiC) was used as reinforcing phase. Erosion-corrosion studies showed that erosion component dominates the total material loss and the composite with highest hardness displaying better erosion-corrosion resistance. Also, addition of MEG to the slurry resulted in lower erosion-enhance corrosion and total material loss due to erosion-corrosion. SEM images of the damaged composite showed that the damage mechanism is dominated by ploughing and indentation.