Effect of Root Flaws on the Fatigue Property of Friction Stir Welds in 2024-T3 Aluminum Alloys


The fatigue experiment of friction stir (FS) welds in 2024-T3 aluminum alloys were performed to investigate the influence of root flaws on the fatigue strength and life of FS welds. The test results of welds with flaws (flawed welds) were compared with the results suggested by the International Institute of Welding (IIW) recommendations and the welds without root flaws (flaw-free) in the published research reports. It was found that there was always existed flaws at the roots of FS welds because of unsuitable welding parameters and the vertical length of the flaws is about 0.31-0.33 mm for the FS butt-welded joint of 4 mm in thickness. The fatigue life of flawed welds is 33-80 times shorter than that of flaw-free welds, and the fatigue characteristic values have decreased from 120.6 MPa for flaw-free welds to 54.7 MPa for flawed welds at 2 x 106 cycles.


Materials Science and Engineering

Keywords and Phrases

Fatigue Performance; Friction Stir Welding; Microstructure; Root Flaws; Aluminum Alloys; Crystal Microstructure; Fatigue Of Materials; Metallographic Microstructure; Welds

International Standard Serial Number (ISSN)


Document Type

Article - Journal

Document Version


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© 2006 Elsevier BV, All rights reserved.

Publication Date

01 Feb 2006