Application of grey-fuzzy logic on the optimal process design of an injection-molded part with a thin shell feature

This paper presents an effective approach for the optimization of machining parameters to an injection-molded part with a thin shell feature (example of cell phone shell consist of PC/ABS material) based on the orthogonal array with the grey relational analysis and fuzzy logic analysis. Through the grey-fuzzy logic analysis, the optimization of complicated multiple performance characteristics can be converted into the optimization of a single grey-fuzzy reasoning grade. In this injection molding process, the machining parameters, namely the mold temperature, melt temperature, filling pressure and filling time are optimized with considerations of multiple performance characteristics including the strength of welding line, the shrinkage and the difference of forming distributive temperature. The experimental results for the optimal setting have obviously shown that the above performance characteristics in the injection molding process can be improved effectively together through this approach.