PSI - Issue 53

Costanzo Bellini et al. / Procedia Structural Integrity 53 (2024) 227–235 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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linear elastoplastic material with isotropic hardening. Table 1 lists the material characteristics used for the current study. These characteristics, which apply to as-built components, that is without post-processing operations, were assessed in earlier investigations by Franchitti et al. (2020).

Fig. 3. Mesh of the numerical model for the three-point bending simulation.

Fig. 4. Boundary conditions of the numerical model

Table 1. Mechanical properties of the Ti6Al4V alloy. Material parameter

Value

Young's modulus

104800 MPa

Poisson's ratio

0.33

Yield stress

857 MPa 2900 MPa

Tangential modulus

3. Results In this section, the results obtained from the experimental tests are exposed and compared to those from numerical runs. Moreover, the additional tests for the determination of the local mechanical parameters, necessary for the model refinement, are described and, finally, the comparison between the experimental curve and that from the enhanced model is reported. In Fig. 5 the load-displacement curve obtained from the three-point bending test is reported and compared with that obtained from the numerical simulation. It is important to underline that the geometry of the simulated specimens was different from the designed one. In fact, as explained in a former work of Di Caprio et al. (2022), the weight of the manufactured specimens resulted lower than that evaluated by CAD; consequently, a reduction of both the truss diameter and the skin thickness was necessary to meet the weight. In particular, the trusses diameter was 0.8183 mm, while the skin thickness was 0.464 mm. Obviously, the measure of the cell side and the dimensions of the specimens remained unvaried. As it can be noted from Fig. 5, there is a mismatch between the experimental curve and the