Optimization of gas protected stir casting process using GRA and TOPSIS

In this paper, multi-response optimization of gas protected stir casting process parameters is carried out for the development of Al2024/red mud composite in order to maximize the responses such as tensile strength and microhardness. Process parameters considered are reinforcement, grain size and blade angle which are varied at three levels and Taguchi's L-27 orthogonal array is used for designing the experiments. Optimum condition of the process parameters are established for the multi-response optimization problem using TOPSIS and grey relational analysis (GRA). Response surface methodology (RSM) is used to derive the regression equations for the responses which are found to be effective within the design space. ANOVA analysis is carried out to study the effect of process parameters on the responses and it is observed that reinforcement is having a dominating effect on both the responses followed by grain size and blade angle. Results of GRA and TOPSIS are found to be in good agreement with each other.