PSI - Issue 74

Mitra Delshadmanesh et al. / Procedia Structural Integrity 74 (2025) 9–16 Mitra Delshadmanesh / Structural Integrity Procedia 00 (2025) 000–000

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Fig. 3. Plot of the von Mises stress [Pa] in sample type A at a load level equivalent to the endurance limit of the sample. This harmonic analysis was conducted with the material parameters of Table 1.

2.2. Experimental results The fatigue tests were recorded by a video camera to obtain precise results for the lifetimes of the samples. Stress values for the notched region of the specimens were derived with the help of Finite Element simulations. The geometry of each sample was checked under an optical microscope, and the precise sample dimensions were used to simulate every sample individually. Thereby, the strain measured at the position of the strain gauge depicted in Fig. 2 was always used as a reference value. The results for the number of loading cycles leading to failure depending on the von Mises stress at the notched specimen are shown in Fig. 4.

Fig. 4. Diagram of conventionally calculated von Mises stress at the notch root versus number of cycles to failure. Points at 10 8 cycles are runouts.