THE MULTI OBJECTIVE OPTIMIZATION OF MECHANICAL PROPERTIES AND BEAD GEOMETRY IN MIG WELDING

In this study the effect of input parameters on weld bead geometry and mechanical properties of the joint are analyzed to obtain the multi objective optimal conditions. The experiment procedure are done by Design of experiments considering four parameters at three levels. Nine trials were done by varying the parameters arc voltage, welding current, gas flow rate, and root gap. The joints obtained are tested for bead geometry, hardness and ultimate tensile strength (UTS). The results obtained are analyzed using Taguchi and Grey relational analysis. By using the taguchi method it was found that the most significant parameter was welding current on the weld properties. The multi objective optimal weld process parameters for minimum bead width, minimum reinforcement and maximum penetration was obtained using grey relational analysis. The multi optimal condition for UTS and Hardness was predicted using grey relational analysis