Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Oct 12;14(20):6003.
doi: 10.3390/ma14206003.

Investigation of Mechanical and Microstructural Properties of Welded Specimens of AA6061-T6 Alloy with Friction Stir Welding and Parallel-Friction Stir Welding Methods

Amir Ghiasvand  1 , Mohammad Mahdi Yavari  2 , Jacek Tomków  3 , John William Grimaldo Guerrero  4 , Hasan Kheradmandan  5 , Aleksei Dorofeev  6 , Shabbir Memon  7 , Hesamoddin Aghajani Derazkola  8
Affiliations

Investigation of Mechanical and Microstructural Properties of Welded Specimens of AA6061-T6 Alloy with Friction Stir Welding and Parallel-Friction Stir Welding Methods

Amir Ghiasvand et al. Materials (Basel). .

Abstract

The present study investigates the effect of two parameters of process type and tool offset on tensile, microhardness, and microstructure properties of AA6061-T6 aluminum alloy joints. Three methods of Friction Stir Welding (FSW), Advancing Parallel-Friction Stir Welding (AP-FSW), and Retreating Parallel-Friction Stir Welding (RP-FSW) were used. In addition, four modes of 0.5, 1, 1.5, and 2 mm of tool offset were used in two welding passes in AP-FSW and RP-FSW processes. Based on the results, it was found that the mechanical properties of welded specimens with AP-FSW and RP-FSW techniques experience significant increments compared to FSW specimens. The best mechanical and microstructural properties were observed in the samples welded by RP-FSW, AP-FSW, and FSW methods, respectively. Welded specimens with the RP-FSW technique had better mechanical properties than other specimens due to the concentration of material flow in the weld nugget and proper microstructure refinement. In both AP-FSW and RP-FSW processes, by increasing the tool offset to 1.5 mm, joint efficiency increased significantly. The highest weld strength was found for welded specimens by RP-FSW and AP-FSW processes with a 1.5 mm tool offset. The peak sample of the RP-FSW process (1.5 mm offset) had the closest mechanical properties to the base metal, in which the Yield Stress (YS), ultimate tensile strength (UTS), and elongation percentage (E%) were 76.4%, 86.5%, and 70% of base metal, respectively. In the welding area, RP-FSW specimens had smaller average grain size and higher hardness values than AP-FSW specimens.

Keywords: aluminum alloy; mechanical properties; parallel-friction stir welding; tool offset.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
The schematic of the FSW, RP-FSW, and AP-FSW processes.
Figure 2
Figure 2
Schematic of milling machine and workpiece.
Figure 3
Figure 3
The tool used in FSW and P-FSW processes.
Figure 4
Figure 4
Schematic of tensile test specimens and related cutting position.
Figure 5
Figure 5
Position of points used for hardness measurement.
Figure 6
Figure 6
Surfaces of welded specimens by three introduced welding techniques.
Figure 7
Figure 7
Welded section cross-section macrograph of AP-FSW and RP-FSW samples.
Figure 8
Figure 8
Comparison of YS values of welded specimens with FSW, AP-FSW, and RP-FSW techniques.
Figure 9
Figure 9
Comparison of UTS values of welded specimens with FSW, AP-FSW, and RP-FSW techniques.
Figure 10
Figure 10
Comparison of E% values of welded specimens with FSW, AP-FSW, and RP-FSW techniques.
Figure 11
Figure 11
Hardness profiles of AP-FSW specimens with different tool offsets.
Figure 12
Figure 12
Hardness profiles of RP-FSW specimens with different tool offsets.
Figure 13
Figure 13
Microstructure of different areas of the sample welded by FSW technique.
Figure 14
Figure 14
Distribution of SZ microstructure for welded specimens using AP-FSW and RP-FSW techniques.
Figure 15
Figure 15
Comparison of average SZ grain size of welded specimens.
See this image and copyright information in PMC

References

    1. Derazkola H.A., Khodabakhshi F., Gerlich A. Friction-forging tubular additive manufacturing (FFTAM): A new route of solid-state layer-upon-layer metal deposition. J. Mater. Res. Technol. 2020;9:15273–15285. doi: 10.1016/j.jmrt.2020.10.105. - DOI
    1. Derazkola H.A., Simchi A. A new procedure for the fabrication of dissimilar joints through injection of colloidal nanoparticles during friction stir processing: Proof concept for AA6062/PMMA joints. J. Manuf. Process. 2020;49:335–343. doi: 10.1016/j.jmapro.2019.12.008. - DOI
    1. Derazkola H.A., Simchi A. Processing and characterizations of polycarbonate/alumina nanocomposites by additive powder fed friction stir processing. Thin-Walled Struct. 2020;157:107086. doi: 10.1016/j.tws.2020.107086. - DOI
    1. Derazkola H.A., Khodabakhshi F. Development of fed friction-stir (FFS) process for dissimilar nanocomposite welding between AA2024 aluminum alloy and polycarbonate (PC) J. Manuf. Process. 2020;54:262–273. doi: 10.1016/j.jmapro.2020.03.020. - DOI
    1. Babu S.D.D., Sevvel P., Kumar R.S., Vijayan V., Subramani J. Development of Thermo Mechanical Model for Prediction of Temperature Diffusion in Different FSW Tool Pin Geometries During Joining of AZ80A Mg Alloys. J. Inorg. Organomet. Polym. Mater. 2021;31:1–17. doi: 10.1007/s10904-021-01931-4. - DOI

LinkOut - more resources