Optimization of welding parameters and microstructure analysis of low frequency vibration assisted SMAW butt welded joints

Vibration-assisted welding has become a successful method for creating welds of high quality. Researchers have recently adopted medium and high frequency assisted welding to achieve better mechanical properties. This study primarily uses low frequency vibration-assisted welding to optimize the process parameters. This study investigates the hardness of 5 mm thick butt-welded MS plates using a novel vibratory approach that vibrates the workpiece while shielding metal arc welding at frequencies between 150 and 250 Hz. The process parameters of current, vibration time, and vibration frequency on the mechanical properties of welded specimens have been optimized using Response Surface Methodology (RSM). Additionally, the microstructure of welded MS plates has been analysed using SEM and XRD examination. Results showed that for the optimal performance in terms of the hardness of welded MS plates, heat input of 135 Amp, vibration frequency of 250 Hz, and vibration duration of 30 s. were required. It has been shown that the most crucial factor affecting the hardness of the welded joint is vibration frequency. The LFVW welded butt joints had a comparable consistent, fine-grained structure with microstructure containing less dendrite suggesting increased hardness and tensile strength values due to weld pool excitation. A tiny structure has been discovered in SEM analysis on a mild steel specimen subjected to vibration-assisted welded.