Vivekanand,
- Research Scholar, Mechanical Engineering department, Faridabad College of Engineering and Management, Haryana, India
Abstract
Robotic pulse Metal Inert Gas (MIG) welding has emerged as an advanced joining technique capable of producing superior weld quality through precise control of welding parameters. The present study evaluates the influence of welding parameters on the microstructural evolution and tensile properties of steel weldments fabricated using robotic pulse MIG welding and compares the results with conventional pulse MIG welding. Microstructural characterization was carried out using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS), while tensile properties were determined using a Universal Testing Machine (UTM). SEM observations revealed the presence of ferrite and austenite phases in the weld metal, heat-affected zone (HAZ), and base metal. Increased welding current, voltage, and wire feed rate promoted grain coarsening, whereas lower heat input facilitated grain refinement and enhanced grain boundary formation. The robotic pulse MIG welds exhibited a more homogeneous and refined microstructure than conventional pulse MIG welds. EDS analysis confirmed the presence of Fe-, Mn-, and Se-rich precipitates, while the concentration of secondary elements such as Si, P, and S decreased with increasing wire feed rate. Tensile testing demonstrated that robotic pulse MIG welded specimens achieved superior mechanical performance, with tensile strength ranging from 241 to 396 MPa and elongation reaching 45.1%. The optimum weld condition was obtained at 106 A current, 16.9 V voltage, 7 mm electrode stick-out, 300 mm/min welding speed, and 6.5 m/min wire feed rate, producing a tensile strength of 394 MPa. The findings indicate that robotic pulse MIG welding enhances microstructural refinement, tensile strength, ductility, and overall weld integrity, making it a reliable alternative to conventional pulse MIG welding for high-quality structural applications.
Keywords: Robotic Pulse MIG Welding, Microstructure, Tensile Properties, SEM–EDS Analysis, Heat-Affected Zone (HAZ)
[This article belongs to Journal of Experimental & Applied Mechanics ]
References
- Weman, MIG Welding Guide, Cambridge, U.K.: Woodhead Publishing, 2012.
- T. Zhang and J. C. Feng, “Microstructure and properties of aluminum-zinc coated steel lap joints fabricated by modified MIG weld brazing process,” Materials Characterization, vol. 58, no. 7, pp. 588–592, 2007.
- Yan, C. Ge, Z. Lin, and W. Shan, “Mechanical properties and microstructure of hybrid laser-MIG welded AA6005-T5 alloy,” Materials Science and Engineering A, vol. 559, pp. 229–235, 2013.
- R. Mirshekari, A. Saatchi, A. Kermanpur, and S. K. Sadrnezhaad, “Effect of welding parameters on microstructure and mechanical properties of welded joints,” Optics & Laser Technology, vol. 54, pp. 151–158, 2013.
- Shanmugarajan et al., “Studies on autogenous laser welding of stainless steel,” Optics and Lasers in Engineering, vol. 51, no. 12, pp. 1272–1277, 2013.
- Zhang, G. Chen, Y. Zhou, and S. Liao, “Optimization of deep penetration welding parameters for stainless steel,” Materials and Design, vol. 53, pp. 568–576, 2014.
- Squillace, U. Prisco, S. Ciliberto, and A. Astarita, “Effect of welding parameters on morphology and mechanical properties of welded joints,” Journal of Materials Processing Technology, vol. 212, no. 2, pp. 427–436, 2012.
- Kumar and V. Kumar, “Residual stress analysis during pulse MIG welding of steel: A review,” International Journal of Engineering Research, vol. 8, no. 4, pp. 112–118, 2020.
- K. Singh, R. Kumar, and P. Sharma, “Investigation of microstructure and mechanical properties of robotic MIG welded steel joints,” International Journal of Mechanical Engineering, vol. 12, no. 12, pp. 1–12, 2025.
- Wang, “The active visual sensing methods for robotic welding: Review, tutorial and prospect,” IEEE Access, vol. 12, pp. 45621–45645, 2024.
- A. Turnage et al., “Quantifying structure–property relationships during resistance spot welding,” Materials Characterization, vol. 112, pp. 10–19, 2016.
- G. Olabi et al., “A review on welding techniques: properties, processes and applications,” Welding International, vol. 37, no. 3, pp. 145–168, 2023.
- Norrish, Advanced Welding Processes, 2nd ed. Cambridge, U.K.: Woodhead Publishing, 2017.
Journal of Experimental & Applied Mechanics
| Volume | 17 | |
| Issue | 02 | |
| Received | 16/06/2026 | |
| Accepted | 23/06/2026 | |
| Published | 14/07/2026 | |
| Publication Time | 28 Days |