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Volume 13 | Issue 7 | Year 2026 | Article Id. IJME-V13I7P122 | DOI : https://doi.org/10.14445/23488360/IJME-V13I7P122

Friction Stir Lap Welding of Al 6061-T6 using Bobbin Tool Designed for Lapped Workpieces

Vijaykumar Natvarlal Modi, Anishkumar H. Gandhi, Vishvesh J. Badheka, Kishan Fuse

Received Revised Accepted Published
27 May 2026 23 Jun 2026 04 Jul 2026 30 Jul 2026

Citation :

Vijaykumar Natvarlal Modi, Anishkumar H. Gandhi, Vishvesh J. Badheka, Kishan Fuse, "Friction Stir Lap Welding of Al 6061-T6 using Bobbin Tool Designed for Lapped Workpieces," International Journal of Mechanical Engineering, vol. 13, no. 7, pp. 281-296, 2026. Crossref, https://doi.org/10.14445/23488360/IJME-V13I7P122

Abstract

Al 6061 has been shown to be a viable candidate material for structural light weighting of transportation vehicles due to its exceptional extrudability, high strength with low weight, and excellent resistance to corrosion. Friction Stir Welding (FSW) has proved its cutting edge for the Aluminum structure assembly in transportation industries due to less heat involvement in the process, mitigates solidification cracking and improves mechanical performance in the assembly. In present study, newly designed bobbin tool was used to investigate weld quality of plates (152 X 102 X 3) mm of Al 6061-T6 in lapped configuration. A bobbin tool with 3 different profiles parts in a pin and concave shoulders was used to investigate effect of different tool rotation (w) speeds- 280, 350 and 445 RPM on Mechanical properties and micro structure of lap joint. Experiments were performed with fixed welding travel speed (v) of 16 mm/min and with conductive heat flow restriction mode. Weld quality was checked with visual inspection, macrostructure, microstructure, tensile-shear strength and hardness. Results showed that newly designed tool is capable to generate strong vertical and horizontal material flow and inter mixing of top and bottom plates materials. All weld samples were fractured from advancing side of bottom plate in tensile-shear test. Maximum Ultimate Tensile Strength (UTS) value and maximum microhardness value was reported as 136.98 N/mm2 and 56.6 HV respectively at tool rotational speed 445 RPM.

Keywords

Lap Welding, Aluminum alloy, Treaded Pin, Microstructure, Mechanical properties, Hooks, Cold lap.

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