A novel method for fatigue assessment of steel plates with thermally cut edges

作者：Peippo J.; Bjork T.; Nykanen T.

来源：Welding in the World, 2018, 62(1): 105-115.

DOI：10.1007/s40194-017-0529-7

• Fatigue strength
• Cut edges
• Design methods
• Fatigue parameters
• Surface roughness
• Residual stress
• Steel grades

The fatigue strength of thermally cut edges shares many similar features with the fatigue strength of a welded joint. Current design standards are valid for geometrically simple, straight, flame-cut edges made of mild steel. However, the applicability of current recommendations is questionable if the geometry is more complicated, if a different (thermal) cutting process is employed, or if any high-strength steel is used. In this study, conventional fatigue analysis methods are applied in order to explain the experimental results obtained by conducting fatigue tests on a cut component made of different steel grades. Since those methods did not explain the experimental results properly, a novel fatigue analysis method for plates with a thermally cut edge was created. This method is a parallel approach to that recently developed at Lappeenranta University of Technology for analyzing fatigue of a welded joint. In addition to the general stress range, this method also takes into account the structural and local geometry of the cut detail, surface roughness, residual stresses due to the cutting process, the external stress ratio, and the effect of the steel grade. The method agreed well with the test results and can be recommended as a new general approach for analyzing the fatigue of cut edges.

• 出版日期2018-1