Effects of High Mean Stress on Fatigue of Nodular Cast Iron

The effects of high mean stresses on the fatigue behavior of nodular iron are studied in this paper. The high mean stresses are applied by two constant- minimum stress test sets and one constant- maximum stress test set. These constant maximum/minimum stress tests, together with standard fully reversed fatigue tests and overload tests, are specially designed not only to show mean stress effects on the fatigue behavior of materials but also to help determine material constants that can be used with a closure-based fatigue method to perform fatigue analysis. The ability of various fatigue methods in predicting mean stress effects on fatigue is also assessed.