Optimization and Analysis of Aluminium A-356.0 Blank Parameters in Sand Casting Process Using Taguchi’s L18 Orthogonal Array Method

Abstract

In this Paper, Aluminium blank (A-356) parameters in sand (green) casting process is optimized by using Taguchi‟s L18 array approach. An attempt was made to obtain optimal settings for the sand casting processes. The casting process involves a number of parameters affecting various casting quality features of the product. In order to optimize the process seven control factors viz., pouring time, D/t ratio, sprue taper, riser surface area, type of sand mixture, quenching medium and normalizing time were selected. Each factor was considered at three levels. For this study three uncontrollable (or noise) factors viz. metal flow rate, pouring temperature and humidity were identified. To capture the effect of noise factors like surface indentation, surface roughness and geometry dimension were measured. An L18 orthogonal array was constructed for the seven factors undertaken, and performing eighteen sets of experiments with their replicates generated the data. The signal-to noise (S/N) ratios were calculated based on the design of experiments. The average values of S/N ratios for each factor at three levels were calculated and were plotted on the graph. Considering the maximum S/N ratios from the graph, the optimum levels of process factors for castings were obtained. A statistical analysis of variance (ANOVA) was performed to see which process parameters are statistically significant. A verification experiment was performed using the identified optimum conditions. The experimental results confirmed the validity of used Taguchi robust design method (L18 approach) for enhancing sand casting process and optimizing the sand casting parameters in aluminium blank casting process.