<abstract xmlns="http://www.w3.org/1999/xhtml"><p> The study presents two approaches to plotting an S-N curve based on the experimental results. The first approach is commonly used by researchers and presented in detail in many studies and standard documents. The model uses a linear regression whose parameters are estimated by using the least squares method. A staircase method is used for an unlimited fatigue life criterion. The second model combines the S-N curve defined as a straight line and the record of random occurrence of the fatigue limit. A maximum likelihood method is used to estimate the S-N curve parameters. Fatigue data for C45+C steel obtained in the torsional bending test were used to compare the estimated S-N curves. For pseudo-random numbers generated by using the Mersenne Twister algorithm, the estimated S-N curve for 10 experimental results plotted by using the second model, estimates the fatigue life in the scatter band of the factor 3. The result gives good approximation, especially regarding the time required to plot the S-N curve.</p></abstract>

The study presents two approaches to plotting an S-N curve based on the experimental results. The first approach is commonly used by researchers and presented in detail in many studies and standard documents. The model uses a linear regression whose parameters are estimated by using the least squares method. A staircase method is used for an unlimited fatigue life criterion. The second model combines the S-N curve defined as a straight line and the record of random occurrence of the fatigue limit. A maximum likelihood method is used to estimate the S-N curve parameters. Fatigue data for C45+C steel obtained in the torsional bending test were used to compare the estimated S-N curves. For pseudo-random numbers generated by using the Mersenne Twister algorithm, the estimated S-N curve for 10 experimental results plotted by using the second model, estimates the fatigue life in the scatter band of the factor 3. The result gives good approximation, especially regarding the time required to plot the S-N curve.

Experimental Method for Plotting S-N Curve with a Small Number of Specimens

PhD, University of Science and Technology in Bydgoszcz Al. Prof. S. Kaliskiego 7 85-796 Bydgoszcz,

University of Science and Technology in Bydgoszcz Al. Prof. S. Kaliskiego 7 85-796 Bydgoszcz,

Polish Maritime Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

{"article-title":"Experimental Method for Plotting S-N Curve with a Small Number of Specimens"}

The study presents two approaches to plotting an S-N curve based on the experimental results. The first approach is commonly used by researchers and presented...

Experimental Method for Plotting S-N Curve with a Small Number of Specimens

Published Online: Jan 20, 2017

Page range: 129 - 137

DOI: https://doi.org/10.1515/pomr-2016-0079

Keywords
high-cycles fatigue, S-N curve, fatigue tests, number of specimens

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Experimental Method for Plotting S-N Curve with a Small Number of Specimens

Published Online: Jan 20, 2017

Page range: 129 - 137

DOI: https://doi.org/10.1515/pomr-2016-0079

Keywordshigh-cycles fatigue, S-N curve, fatigue tests, number of specimens

© 2017

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Keywords
high-cycles fatigue, S-N curve, fatigue tests, number of specimens