Fatigue assessment of 5059 aluminum alloy thin plate welded joint accounting for welding deformation and residual stress

ABSTRACT

Compared with the traditional 5083 or 6082 aluminum alloy, 5059 has better mechanical properties and corrosion resistance. The traditional fatigue class curve is no longer suitable for fatigue strength evaluation of 5059 marine aluminum alloy structures. Meanwhile, the welding structure of thin aluminum alloy has bigger initial welding defects, resulting in more obvious stress concentration effect at the corner. Large welding deformation brings great challenges to the precision evaluation of stress concentration effect and fatigue strength near corners. Therefore, in order to accurately consider the influence of welding defects, the welding temperature field and stress field of 5059 aluminum alloy structures were simulated and analyzed systematically. In addition, considering the influence of welding deformation and residual stress, the fatigue assessment of 5059 aluminum alloy welded joints based on hot spot stress was carried out, and the fatigue class curve suitable for thin plate cruciform joint of 5059 was renewed.

KEYWORDS:

• 5059 aluminum alloy
• thin plate cruciform joint
• welding deformation and residual stress
• hot spot stress
• fatigue strength

Acknowledgements

The authors also wish to extend their thanks to Dr. Enqian Liu, University of Strathclyde, for his helpful discussion about this work.

Disclosure statement

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

Additional information

Funding

The research project is supported by the Fundamental Research Funds for the Central Universities, China [WUT: 2021III032JC; WUT: 202402001] and Sanya Science and Education Innovation Park of Wuhan University of Technology, China [No. 2020KF0038].