Multi-objective Optimization of the EMS Processed IC by Grey-fuzzy Method

Abstract

In the present investigation, investment casting (IC) has been combined with the electromagnetic stirring (EMS) process. The process parameters are chosen on the basis of literature review on IC and EMS processes and these parameters are shell preheat temperature, stirring current, stirring time and pouring temperature. The responses are linear shrinkage, volumetric shrinkage and tensile strength of the investment cast parts. The experiments were conducted as per Taguchi's L9 orthogonal array (OA). As the optimal condition determined for each response was different, grey-fuzzy method was used to combine individual objective functions into a single objective function so as to form a common optimal setting for all the chosen responses. Further, confirmative experiments were done at the obtained common optimal condition to validate the adopted approach in enhancing the quality of the investment cast parts.