The Influence of Notch Geometric Size in the Fatigue Strength of Steel

Abstract:

The fatigue behavior of notch specimens has been investigated in this manuscript. It is shown that notch geometric size has apparent effect for fatigue strength of specimens. The blunt notch is used in test. It is concluded that geometric size effect depends on the stress gradient and can be estimated with the help of the linear elastic fracture mechanics. The influence of notch size for fatigue strength can be explained with geometric factor. The plastic strain play an important role in fatigue crack initiation with notch gets sharper reach certain magnitude limit, and fatigue strength is lower than the predicted by geometric size factor effect. The method does not apply fatigue strength of the sharper notch. Another estimation method shall be used to that kind of notches.

• Periodical: Applied Mechanics and Materials (Volumes 602-605)
• Pages: 167-171
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.602-605.167
• Online since: August 2014
• Authors: Yong Zhuang Yuan*
• Keywords: Fatigue Strength, Geometric Size Effect, Notch

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