Parametric optimization of surface roughness castings produced by Evaporative Pattern Casting process

In the present paper Taguchi's approach has been applied to the Evaporative Pattern Casting (EPC) process of Al–7%Si alloy to determine the most influential control factors which will provide better and consistent surface roughness to the castings regardless of the noise factors present. In order to evaluate the effect of process parameters such as grain fineness number, time of vibration, degree of vacuum and pouring temperature on surface roughness of EPC process castings, the Taguchi parameter design and optimization approach is used. Through the Taguchi's parameter design approach, optimal levels of process parameters have been determined. The results indicated that the grain fineness number, time of vibration, degree of vacuum were the significant parameters in deciding the surface roughness of Al–7%Si alloy castings. Pouring temperature was the insignificant parameter. The predicted optimal value of surface roughness of Al–7%Si alloy castings produced by EPC process was 2.31 μm. The results were confirmed by further experiments.