*2.3. Fatigue Testing*

The three-point bending fatigue tests were performed at the MaSTeR Lab laboratories in Forlì (University of Bologna), with the use of a 100 kN servo-hydraulic testing machine (Italsigma, Forlì, Italy). The experimental setup is illustrated in Figure 5. The tests were conducted under force-controlled conditions at four different stress levels, with a constant R-ratio of R = 0.1. The stress concentration factor for the given specimen configuration was Kt = 1.3, which resulted in maximum stresses at the notch ranging from 220 to 260 MPa.

**Figure 5.** Experimental setup for three-point bending fatigue tests.
