Optimization of process parameters of friction welding of UNS S31803 duplex stainless steels joints

This article presents an approach based on Taguchi method and Grey relational analysis to optimize process parameters of friction welding of UNS31803 duplex stainless steel. The main objective is to maximize mechanical properties like tensile strength, hardness and impact toughness and to minimize corrosion rate. Heating pressure, heating time, upsetting pressure and upsetting time were the four process parameters taken each at three levels. According to Taguchi quality design concept, an L9 orthogonal array was selected for experiments. The best combination of process parameters was found by both Taguchi method and Grey relational analysis. The influence of the process parameters on overall quality characteristics of the friction welding process was evaluated by the analysis of variance (ANOVA) method. The confirmation test results with optimal parameters confirmed the effectiveness of the proposed method in this study. Later, comparison was done between Taguchi method and Grey relational analysis on the basis of improvement in multiresponse signal to noise (S/N) ratio over initial process parameters. Grey relational analysis was proved to be a better technique than Taguchi method for optimization of multiple responses.