Statistical Modeling for Low Cycle Fatigue  
Author D. Gary Harlow




Abstract Low cycle fatigue (LCF) is a common loading condition experienced by structural components. LCF is usually defined as the fatigue cycles to failure are less than 105. In order to certify and qualify a material for an application that requires high reliability for operation and safety, fundamental material properties must be experimentally investigated and validated. The well documented strain–life approach serves as the underlying experimental method for the investigation herein. The purpose of this paper is to investigate the statistical variability and appropriately model that variability for key material properties in LCF. Specifically, the elastic modulus is a critical material property in the strain–life method for LCF which is considered. Also, the variability associated with the median behavior in a strain–life graph for the data is examined. The ensuing analyses are based on data for a typical structural steel. The distribution functions considered for characterizing the material parameters are in accord with common practice, i.e., the normal and Weibull distribution functions. The strain–life computation employs the standard Coffin–Manson relationship.


Keywords Coffin–Manson Approach, Low Cycle Fatigue, Modulus of Elasticity, Strain–Life Analysis, Weibull distribution
    Article #:  19194
Proceedings of the 19th ISSAT International Conference on Reliability and Quality in Design
August 5-7, 2013 - Honolulu, Hawaii, U.S.A.