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

Abstract:

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

• Periodical: Key Engineering Materials (Volumes 353-358)
• Pages: 2061-2064
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.353-358.2061
• Online since: September 2007
• Authors: Yong Yun Nam, Seung Ho Han, Jeong Woo Han, Byung Chun Shin
• Keywords: Automobile Hot Spot Stress, Fatigue, Representative Stress, S-N Curve, Weld Joint

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