Experimental Investigation of Mig Welding Parameters for Improving Strength of Welded Joints

The aim of the present study is to show the influence of different input parameters such as welding current, welding voltage and wire feed rate to identify the variations in the output responses such as Corrosion potential, grain area and hardness on mild steel using Metal Inert Gas Welding (MIG). Potentio-dynamic polarization studies are carried out to determine the pitting corrosion resistance. The selected three input parameters are varied at three levels. On the analogy, nine experiments are performed based on L9 orthogonal array of Taguchi’s methodology in Minitab statistical software. Analysis of variance (ANOVA) is employed to find the levels of significance of input parameters. In this thesis, Welding voltage has significant effect on output responses when compared to welding current and wire feed rate. Response tables and graphs are used to find the single optimal responses using Minitab18 statistical software. Grey relational analysis has been carried out to find the multi response optimal parameters. The confirmation experiments are carried out to validate the optimal results.