Enhancing shielded metal arc welding performance through process parameter optimization with low-frequency vibration assistance

Vibration-assisted welding has emerged as a high-quality weld production technique, with recent studies focusing on medium and high-frequency applications to enhance mechanical properties. This research aims to investigate and optimize process parameters using low-frequency vibration-assisted welding. The Taguchi method was employed to identify optimal conditions for improved weld quality. Shielded Metal Arc Welding (SMAW) was used in conjunction with a low-frequency (100 Hz) vibratory setup to impart controlled vibration to the workpiece during welding. The effects of welding current, vibration time, and frequency were optimized using Taguchi methodology and response surface technique based on an L27 orthogonal array design. The results indicate that the most important factor affecting the required hardness, tensile strength, and impact strength is vibration frequency. Vibration-assisted welding of mild steel at optimized parameters 120 A current, 100 Hz frequency, and 60 s vibration time resulted in a maximum hardness of 97.16 RHN and enhanced impact strength. Low heat input, 100 Hz vibration frequency, and 100 s vibration time yielded optimal tensile strength. SEM analysis revealed a refined microstructure in the weld zone, attributed to weld pool excitation, which promotes finer grain formation and improved mechanical properties.