Mathematical and experimental examination of the effect of the stepped pin tool profile on the characterization of AA 6061-T6 underwater friction stir welding

Abstract

This research paper presents the mathematical model to design a stepped pin profile tool and its durability index. A mathematical model is being developed by considering tools that should generate the same heat as conventional conical tools and stepped tools by varying the shoulder to pin diameter ratio (D/d). Aluminum alloy AA6061-T6 with a thickness of 6 mm fabricated using a butt-type weld configuration and newly developed conical stepped pin profile tools with water as a cooling medium. The result shows that a conical stepped tool shows better mechanical properties of the welded joints compared with a conventional conical tool. When compared to other stepped conical pin profile tools, one with a (D/d) of 3 has superior mechanical and microstructural properties and as the D/d ratio increases, the tool pin durability index falls.

The Effect of Cooling Temperature on Microstructure and Mechanical Properties of Al 6061-T6 Aluminum Alloy during Submerged Friction Stir Welding

“…The fracture occurred in the SZ for joints welded at a low rotation speed, but the fracture location shifted to TMAZ and HAZ for joints welded at a higher rotation speed. Wakchaure and Thakur [22] developed a mathematical model for underwater FSW of AA 6061-T6 using a stepped pin tool profile. They found results of a mathematical model that were comparable with experimental results.…”