Experimental Investigation of Mechanical Properties and Characterization of Mild Steel Weldment Fabricated Using Pulse/Robotic Pulse Metal Inert Gas Welding Processes

This paper presents the experimental analysis of the mechanical and microstructural properties of mild steel IS3502 weldments welded using conventional and robotic pulse welding techniques. The mechanical characteristics were tested using a universal tensile testing machine (UTM), and the morphological and elemental percentages of weldments were investigated using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Five input parameters, such as shielding gas, average current (A)/voltage (V), electrode stick-out length (mm), welding speed (mm/min), and wire feed rate (m/min), were investigated. The tensile and yield strengths of the weldments have been increased by 3.14% and 5.35% by using the robotic pulse MIG welding process as compared to the conventional pulse MIG welding process. In the same way, in conventional pulse MIG welding, the microstructure of both the heat-affected zone (HAZ) and welded zone (WZ) of the weld specimen formed using robotic pulse MIG welding was shown to be more uniform and finer.