Study on Partial Replacement of Silica Sand With Alternatives and Its Effect on Sand Mould and Casting Properties

Abstract

In the current scenario the demand for reduction of silica sand usage in making sand moulds in the metal casting industry is increasing day by day. The non-silica alternatives will help the foundries to not only get in line with new regulations but also protect the foundry workers and minimizing the compliance costs. The non-silica alternatives such as clay, bio-waste, bagasse-ash and nano-SiO2 in different proportions are added to silica sand to prepare moulding sand. The effect of these alternatives on mould sand properties such as permeability, green shear strength and green compression strength are studied. The aluminium alloy 6061 castings were fabricated in the sand mould prepared using these non- silica alternatives. Effect of these materials on the grain size, surface roughness and mechanical properties of aluminium alloy 6061 castings were studied. Out of all, the silica sand/15%bagasse-ash combination was found more suitable for producing aluminium alloy 6061 castings with high yield strength, ultimate tensile strength and low surface roughness values. The ranking of combinations based low surface roughness and high strength values of aluminium alloy 6061 castings is, bagasse-ash > bio-waste > nano-SiO2 > clay.