5.2 Model validation for other materials
Test results for other materials were collected to validate the proposed model, including Ti-6Al-4V47, Al-2024-T4248, 30CrMnSiA52, 30NiCrMoV1246, Maraging steel49, GS6153, ENAW600551, P355NL150, S45C45, and DTD68317. To illustrate the model’s applicability to multiple materials, a set of universal parameters (A =1,m =0.45) instead of material-dependent parameters was used to predict the residual life. The equation is written as follows:
As shown in Fig 9, these test results17,45–53 were divided into four groups according to the value ofNf 1/Nf 2. For the test results with low life ratios(e.g., 1<Nf 1/Nf 2≤5), the residual cycle life fraction is almost all less than unity and decreases continuously with the preload cycle life fraction. For test results with higher life ratios, it is evident that the residual cycle life fraction is increased within a range of preload cycle life fractions. The proposed model’s predictions for each data group are also plotted in the figure. TheNf 1/Nf 2used in the proposed model is the maximumNf 1/Nf 2for each group. It can be seen that the proposed model provides an appropriate description of the data for different ranges of life ratios.