Abstract
The present paper addresses the problem of designing aluminium friction stir (FS) welded joints against multiaxial fatigue. After developing a bespoke FS welding technology suitable for joining aluminium tubes, some one hundred welded tubular specimens of Al 6082-T6 were tested under pure axial, pure torsional and biaxial tension-torsion loading. The influence was explored of two independent variables, namely the proportional or non-proportional nature of the biaxial loading and the effect of axial and torsional non-zero mean stresses. The experimental results were re-analysed using the Modified Wöhler Curve Method (MWCM), with this bi-parametrical critical plane approach being applied in terms of nominal stresses, notch stresses, and also the Point Method. The validation exercise carried out using these experimental data demonstrated that the MWCM is applicable to prediction of the fatigue lives for these FS welded joints, with its use resulting in life estimates that fall within the uniaxial and torsional calibration scatter bands. The approach proposed in the present paper offers, for the first time, a complete solution to the problem of designing tubular FS welded joints against multiaxial fatigue loading.
DOI
10.1016/j.ijfatigue.2016.08.010
Publication Date
2017-08-01
Publication Title
International Journal of Fatigue
Volume
101
ISSN
0142-1123
Embargo Period
2018-02-01
Organisational Unit
School of Engineering, Computing and Mathematics
First Page
282
Last Page
296
Recommended Citation
Susmel, L., Hattingh, D., James, M., & Tovo, R. (2017) 'Multiaxial fatigue assessment of friction stir welded tubular joints of Al 6082-T6', International Journal of Fatigue, 101, pp. 282-296. Available at: https://doi.org/10.1016/j.ijfatigue.2016.08.010