Parametric optimisation of gas metal arc dissimilar welding on AISI 304 stainless steel and low carbon steel

The weld-bead geometry and mechanical properties of the AISI 304 stainless steel and low carbon steel gas metal arc dissimilar weldments were optimised within a process window (wire feed rate (66-96 mm/s), voltage (19-25 V) and welding speed (3-6 mm/s)). The variations of the weld-bead width and mechanical properties with the processing parameters were analysed and presented. Significant changes in the microstructure of the weld zone with the heat energy inputs were observed. All the three utilised parameters contributed significantly to the bead width, ultimate tensile strength (UTS) and hardness of the weldments. The welding speed contributed most significantly to the UTS and bead width while the voltage has the most significant effect on the hardness. Optimum weld qualities including continuous joint, high tensile strength (422 MPa) and high hardness (112 HB) were found at 84 mm/s wire feed rate, voltage of 25 V and speed of 3 mm/s.