Determination of Fatigue Life on the Basis of Experimental Fatigue Diagrams under Constant Amplitude Load with Mean Stress

Abstract:

The paper deals with a comparison of fatigue life calculations, obtained on the basis of classical Basquin diagrams and approximated diagrams acquired with the use of the section method, which allows us to fit the diagrams shape to real material properties. While comparing the calculation results, literature data concerning fatigue tests of welded cruciform specimens from high performance low-alloy steel HSLA-80 presented by Kihl and Sarkani as well as of smooth specimens out of the aluminum alloy 75S-T6 by Grover et al. has been used. It has been noticed that the calculations performed with the use of fatigue diagrams approximated using the section method reflect the true behavior of the material. The models by Niesłony-Böhm and Smith-Watson-Topper compensating the influence of the mean stress gave similar results.

• Periodical: Materials Science Forum (Volume 726)
• Pages: 33-38
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.726.33
• Online since: August 2012
• Authors: Adam Niesłony, Michał Böhm
• Keywords: Fatigue, Mean Stress, Section Method, Stress Ratio

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