A combinatorial approach to optimize the properties of green sand used in casting mould

Abstract

The uses of cast iron have been well documented since the fifth century. Most of the current small scale production of cast iron is carried out using the sand casting process. The present study investigates the sand casting process parameters of green sand to determine the optimal control factors on shear strength, compression strength and permeability with different compositions of bentonite, dextrin, coal powder, and water. To determine the considerable effect on three responses namely, shear strength, compression strength and permeability of green sand, eighteen experimental runs, with two replications, have been conducted using L18 orthogonal array. The experimental results were analyzed using Grey Relational Analysis (GRA); Grey Relational Grade (GRG) was calculated to determine the rank and influence of the control parameters for the three different responses. From the analysis of experimental results, it was observed that bentonite plays a significant role in the green sand strength, when compared to coal powder, dextrin and water. The results showed that elevated bentonite and coal powder in the sand could prominently improve the shear strength, compression strength and permeability. The experimentation demonstrated that the sand strength reduces as the amount of dextrin increases, within the range of specifications considered.