PSI - Issue 33

Mohammad Azadi et al. / Procedia Structural Integrity 33 (2021) 181–188 Azadi & Aroo / Structural Integrity Procedia 00 (2021) 000 – 000

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Fig. 6. The pareto diagram for the normal scale of the fatigue lifetime.

Fig. 7. The pareto diagram for the logarithmic scale of the fatigue lifetime.

To find the qualitative trend of input parameters on the output, Fig. 8 is presented. Based on these results, as expected, by increasing the stress, the fatigue lifetime decreased. However, by the addition of nano-particles, the fatigue lifetime reduced. By the heat treatment, the fatigue lifetime of the material enhanced. Finally, by the pre corrosion, the degradation occurred in the material performance. As a note, the stress was a continues parameter and therefore, a continuous line was used in the regression analysis. For other parameters, data were discrete and two points could be observed for each state.

Fig. 8. The pareto diagram for the logarithmic scale of the fatigue lifetime.