A Representative Stress Model Removing Weld Joint Type Dependency of S-N Curve



The hot spot stress or the notch strain alleviates the welding detail dependency of S-N curve to some extent. This paper suggests a new stress model which alleviates the dependency further, thus the fatigue strengths of several welding details of same material can be evaluated with the S-N curve of the base material. A stress at the hot spot of a weld joint is decomposed into two components; linear rising one, and rapid rising one which is inversely proportional to the distance from the hot spot. For the stress decomposition, a formula is proposed with which the configuration of stress distribution near a hot spot is fitted exactly. The new stress model makes use of a geometric characteristic of the stress distribution curve by the formula. The stress model is applied to five different weld joints. As the result, the experimental fatigue data are plotted very closely to the S-N curve of the base material




Yu Zhou, Shan-Tung Tu and Xishan Xie




Y. Y. Nam et al., "A Representative Stress Model Removing Weld Joint Type Dependency of S-N Curve", Key Engineering Materials, Vols. 353-358, pp. 2061-2064, 2007


September 2007




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