Practical Failure Analysis

, Volume 3, Issue 3, pp 83–88 | Cite as

A plausible strategy for modeling fatigue life variation

  • J. Raphael
Peer Rerieved Articles


In this paper stochastic modeling is used to predict fatigue life uncertainty by simulating small variations in strain-life material constants. The Monte Carlo method,[1] using either known cumulative distribution functions (CDFs) for the material constants and/or postulated CDFs, provides the mechanism to generate a set of failure data. These data are analyzed, using ordinary statistical techniques, to develop the Weibull CDF for cycles to failure. It is seen that small variations (∼±15%) in values of the strain-life constants result in large variations (∼600%) in predicted fatigue life at moderate strain. The often-observed phenomenon that spread in fatigue data is greater at lower strain is also described by the stochastic model.


fatigue life variation Monte Carlo simulation strain life analysis 


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Copyright information

© ASM International - The Materials Information Society 2003

Authors and Affiliations

  • J. Raphael
    • 1
  1. 1.Columbus McKinnon CorporationAmherst

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