Weld toe versus root fatigue failure mode and governing parameters: A study of aluminum alloy load-carrying fillet joints. (March 2023)

• Record Type: Journal Article
• Authors: Xing, Shizhu; Pei, Xianjun; Mei, Jifa; Dong, Pingsha; Su, Shaojuan; Zhen, Chunbo
• Is Part Of: Marine structures. Volume 88(2023)
• Publication Date: 2023-03
• Subjects: Aluminum alloys -- Load-carrying fillet welds -- Traction stresses -- Weld root cracking -- Fatigue failure; Naval architecture -- Periodicals; Offshore structures -- Periodicals; Architecture navale -- Périodiques; Structures offshore -- Périodiques; Naval architecture; Offshore structures; Periodicals; 620.4162
• DOI: 10.1016/j.marstruc.2022.103344
• Languages: English
• ISSNs: 0951-8339

Abstract

Abstract: In load-carrying fillet welded connections, two fatigue failure modes are possible i.e. weld toe cracking and weld root cracking. The fatigue life associated with weld root cracking is typically much lower than weld toe cracking, exhibiting a wider scatter band, especially for welded aluminum alloys. This paper examines fatigue failure mode transition behaviors in load-carrying fillet welds made of aluminum and their governing parameters, among plate thickness, weld penetration, joint misalignment, weld material, and ultrasound impact peening(UIP). Through both experimental and theoretical studies, a quantitative fillet weld sizing criterion was proposed for avoiding weld root cracking in fillet-welded aluminum connections. Highlights: Presented an analytical weld throat stress model incorporating weld penetration and unequal weld leg size. Conducted fatigue testing with a systematic variation in fillet weld sizes over two representative plate thicknesses. Examined fatigue failure mode transition behaviors in fillet welded aluminum alloys and their governing parameters. Proposed a quantitative fillet weld sizing criterion for avoiding weld root cracking in fillet welded aluminum alloys.