Friction Stir Spot Welding – A validation Study for Optimal Welding Parameters of Aluminum Alloy 6061

Abstract One of the important parameters of Refill Friction Stir Spot Welding is the so-called basic position of the tool. This is the arrangement of the pin and sleeve which occurs when the tool is plunged into the material. The basic positions can be divided into two categories. In the first category, the sleeve and the pin are above the sheet surface or below sheet surface and in the second category the pin is retracted within the sleeve or protrudes from it. The aim of the work was to test four settings of the basic position, and then determine the best setting of the basic position, without changing the other welding parameters. Joints made of an aluminum alloy 2024-T3 sheet having a thickness of 1.0 mm and an aluminum alloy D16UTW sheet having a thickness of 0.6 mm were analysed. The best setting of the basic position was determined based on assessment of the force carried in shear test, macrostructure and weld face of the joints.

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Refill Friction Stir Spot Welding of Dissimilar 6061/7075 Aluminum Alloy

High Temperature Materials and Processes ◽

10.1515/htmp-2017-0139 ◽

2019 ◽

Vol 38 (2019) ◽

pp. 69-75 ◽

Cited By ~ 1

Author(s):

Zhenlei Liu ◽

Kang Yang ◽

Dejun Yan

Keyword(s):

Aluminum Alloy ◽

Spot Welding ◽

Joint Strength ◽

Shear Failure ◽

Failure Load ◽

Friction Stir Spot Welding ◽

Welding Parameters ◽

Plunge Depth ◽

Friction Stir ◽

Lap Shear

AbstractRefill friction stir spot welding (RFSSW) was used to join 6061-T6 and 7075-T6 aluminum alloys in this work. Different sheet configurations and welding parameters were used to optimize joint strength. The effect of sleeve plunge depth on the microstructure and mechanical properties of the joints were investigated. The results showed that no defects were obtained when 6061-T6 aluminum alloy was placed as the upper sheet. The lap shear failure load of the joint using 6061-T6 aluminum alloy as the upper sheet was higher than that using 7075-T6 as the upper sheet. The maximum failure load of 12,892 N was attained when using the sleeve plunge depth of 3.6 mm. The joint failed at the upward flowing 7075 near the hook.

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Effect of Modified Pin Profile and Process Parameters on the Friction Stir Welding of Aluminum Alloy 6061-T6

Advances in Materials Science and Engineering ◽

10.1155/2016/4567940 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 6

Author(s):

J. C. Verduzco Juárez ◽

G. M. Dominguez Almaraz ◽

R. García Hernández ◽

J. J. Villalón López

Keyword(s):

Mechanical Properties ◽

Aluminum Alloy ◽

Friction Stir Welding ◽

Material Flow ◽

Flow Behavior ◽

Tensile Tests ◽

Welding Parameters ◽

Friction Stir ◽

Aluminum Alloy 6061 ◽

Alloy 6061

This work deals with the effect of a new “bolt-head” pin profile on the friction stir welding performance of the aluminum alloy 6061-T6, compared to traditional pin profiles. Friction stir welding parameters such as the tool rotation speed and the welding speed were investigated together with the different pin profiles; the results show that the new “bolt-head” pin profile leads to better mechanical properties of welded specimens. The pin profiles used in this work were the straight square (SS), straight hexagon (SH), taper cylindrical (TC), and the straight hexagon “bolt-head” (SHBH). It was found that the last pin profile improves the material flow behavior and the uniform distribution of plastic deformation and reduces the formation of macroscopic defects on the welded zone. Mechanical tensile tests on welded specimens were performed to determine the tensile strength: the specimens welded with the SHBH pin profile have shown the highest mechanical properties. An approach is presented for material flow on this aluminum alloy using the SHBH pin profile, which is related to the improvement on the resulting mechanical properties.

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Effects of Process Parameters on Friction Stir Spot Welding of Aluminum Alloy to Advanced High-Strength Steel

Volume 1: Processing ◽

10.1115/msec2016-8589 ◽

2016 ◽

Cited By ~ 1

Author(s):

Kai Chen ◽

Xun Liu ◽

Jun Ni

Keyword(s):

Aluminum Alloy ◽

Cross Sections ◽

Spot Welding ◽

Dwell Time ◽

High Strength ◽

Friction Stir Spot Welding ◽

Thin Layers ◽

Weld Strength ◽

Friction Stir ◽

Alloy 6061

Friction stir spot welding (FSSW) process has been successfully applied for joining aluminum alloy 6061 to TRIP 780/800 steel. Effects of tool plunge speed and dwell time on the weld strength were studied through design of experiments and analysis of variance. It is shown that dwell time is a more dominant parameter in affecting the weld strength than plunge speed. Cross sections of weld specimens show the formation of hook with a swirling structure. Higher magnified SEM view with EDS analysis reveals the swirling structure to be composed of alternating thin layers of steel and Al-Fe intermetallic compounds (IMCs). During tensile shear test, cross nugget failure is the only failure mode. Cracks are initiated in the swirling structure at the tensile side of the weld nugget and cleavage feature can be observed on the fractured surface.

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