Density Optimization of Slurry of Coating Material Used in the EPC Process Through Taguchi's Parameter Design Approach

Abstract

In the Evaporative Pattern Casting (EPC) process, the refractory coating plays an important role with the polystyrene pattern. It not only provides refractory protection to ensure no metal penetration and smooth surfaces, but it also acts as a membrane between the decomposing polystyrene pattern and the unbounded sand mass. In general zircon flour is used as a coating material in the EPC process but it is very costly. An attempt has been made to study the properties of the fly ash with the zircon flour and bentonite. The Taguchi design of experiments and analysis of variance (ANOVA) are employed to analyze the influence of the process parameters (Zircon flour, fly ash, and bentonite) on density of slurry of the coating material in the EPC process. In Taguchi method, a three-level orthogonal array has been used to determine the S/N ratio. The results reveal that the zircon flour, fly ash, and bentonite are the significant parameters. Zircon flour is the most significant factor influencing the response variable investigated. Rest of significant terms provides secondary contribution to density of coating material. The predicted optimal density of slurry of coating material is 1.44 gm/cm3.