PSI - Issue 24

Giulia Morettini et al. / Procedia Structural Integrity 24 (2019) 349–359 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 1. Geometry of specimens and schematic representation of their build orientation. Load-controlled fatigue tests were carried out using an Instron 1342 electromechanical testing machine, with sinusoidal signal in uniaxial tension. The load frequency has been set 20 or 25 , depending on the applied load level, but for all cases, the load ratio has been set to zero = 0 . At 2 × 10 6 cycles the test was considered to be a run-out. Approximately 2 specimens were tested for each load case. The fracture surface of all the specimens for each set (vertical or horizontal) was characterized by SEM. 3. Results

3.1. Fatigue test results

The results of the fatigue test of Vertical and Horizontal specimens are shown in Figure 2 and 3, respectively. Data, obtained from a statistical elaboration, are presented in terms of maximum stress amplitude related to the number of cycles corresponding to the failure. The “run out” specimens have been marked with an arrow. (a)