Microstructure and mechanical properties of friction stir spot welded dissimilar aluminum alloys

ABSTRACT

The present study was the result of an investigation of friction stir spot (FSS)-welded similar aluminum alloys 2024-T3 joint and 7075-T6 joint and dissimilar aluminum alloy 2024-T3-7075-T6 joint. The mechanical, microstructural, and tribological behavior of the different FSS-welded specimens were characterized for effects of influence of the input process parameters. The dissimilar FSS-welded 2024-T3-7075-T6 joint exhibited uniform distribution in material flow in the welded zone. A marked improvement in microhardness was noted when it increased from 30 to 40.94 HV, while an increase in tensile strength from 128 to 166.3 MPa was observed for the FSS-welded dissimilar 2024-T3-7075-T6 joint alloy. The dissimilar alloy weld joint exhibited improved microhardness and tensile properties than their counterparts in both variants of the similar FSS-welded specimens, with a 35.6% increase in microhardness for the bottom plate in welded nugget zone and improvement of 13.14% and 5.54% in ultimate tensile strength when compared to aluminum alloy 2024-T3 joint and 7075-T6 joint under same welding parameters.

KEYWORDS:

• Friction stir spot welding
• microstructure
• microhardness
• tensile
• dissimilar

Acknowledgments

The authors are grateful for the support rendered by Noorul Islam Centre for Higher Education and Agni College of Technology. They sincerely thank their respective Departments of discipline for lending their support.

Nomenclature

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Disclosure statement

No potential conflict of interest was reported by the author(s).

Funding

There is no Funding and Conflict of interest.