Effect of Wall Thickness on the Quality of 1060 Aluminum Produced by Sand Casting

The demand for thin walled sections in the industry is continuously increasing due to their light weight. However, the production of thin wall sections (<2 mm) using sand casting process present a huge challenge in the foundry industry. This paper will investigate the filling defects which are associated with thin walled sections, thus affecting the quality of 1060 aluminium casting using sand casting process as a manufacturing process. The results showed quick solidification of thin walled section (1mm-2.5 mm) before the metal completely filled the mould cavity. Some of the important factors which contributed to this quick solidification were wall thickness, backpressure and presence of junctions. The higher the number of junctions the higher the backpressure and the lower the fillability. A small increase in wall thickness reduced the backpressure which increased the metal flow. The temperature of the molten metal remained constant at different places for all different test samples. A slight increase in wall thickness yielded a minimum of 12.5% and a maximum of 32% increase in fillability. It was observed that as the wall thickness increases, so does the fillability.