PREDICTION OF FATIGUE LIFE WITH AN EQUIVALENT DAMAGE MODEL

In this paper an equivalent damage model for prediction of fatigue life is developed. The results predicted by this model have been compared with a set of random spectra experimental results. In the experiments materials Ly12-Cz and 30CrMnSiNi2A are used, the tests are performed under three kinds of random load spectrum with two stress levels, involving twelve conditions. In total thirty one specimens are tested, the average value of the prediction ratio is 1.06 with standard deviation +0.173. Requisite accuracy for engineering and a physical interpretation of crack growth are obtained.