Effect of weld geometric profile on fatigue life of cruciform welds made by laser/GMAW processes

• Published in: Marine structures 2006, Vol.19 (1), p.1-22
• Main Authors: Caccese, V., Blomquist, P.A., Berube, K.A., Webber, S.R., Orozco, N.J.
• Format: Article
• Language: English
• Subjects: Applied sciences; Building structure; Buildings. Public works; Construction (buildings and works); Cruciform; Exact sciences and technology; Fatigue; Full-penetration welds; Ground, air and sea transportation, marine construction; Hybrid welds; Hydraulic constructions; Laser welds; Marine; Marine construction; Metal structure; Offshore structure (platforms, tanks, etc.); Stress-concentration factors; S–N Curves
• ISSN: 0951-8339; 1873-4170
• DOI: 10.1016/j.marstruc.2006.07.002

The effect of weld geometric profile on fatigue life of laser-welded HSLA-65 steel is evaluated. Presented are results of cruciform-shaped fatigue specimens with varying weld profiles loaded cyclically in axial tension–compression. Specimens with a nearly circular-weld profile were created at 133 cm/min, as part of this effort, with a hybrid laser gas-metal-arc welding GMAW (L/GMAW) process. The ability of the laser-welding process to produce desirable weld profiles resulted in fatigue life superior to that of conventional welds. Comparison of finite-element analyses, used to estimate stress-concentration factors, to the hot spot and mesh insensitive approaches for convergent cases with smooth weld transitions is presented in relation to the experimental results. When a geometry-based stress concentration factor is used, the fatigue tests show much less variability and can be lumped into one master curve.