Influence of Specimen Geometry and Notch on Fatigue Lifetime and Fracture Behavior of Aluminum-based Nanocomposite Under Stresscontrolled Fully-reversed Bending Loads

Introduction: In the present article, the effect of the specimen geometry and the sample notch was studied on the high cycle fatigue lifetime and fracture behavior of the aluminum-based nanocomposite, which was registered as a patent in Iran (Patent No. 99513, 2020).Methods: For such an objective, rotary fully-reversed bending fatigue tests were performed on smooth and notched specimens, with the frequency of 100 Hz. Then, simulated results using the MSC Fatigue software were calculated and compared to the fatigue lifetime in the experiments for validation. Moreover, scanning electron microscopy was utilized to observe the fracture surface of failed samples after testing.Results: Obtained results indicated that the fatigue lifetime increased by enhancing the sample diameter. However, the fatigue lifetime reduced when the stress concentration factor changed from 1.0 to 2.9.Conclusion: All samples with three geometries had a brittle fracture due to cleavage and quasicleavage marks on the fracture surface.