PSI - Issue 83

Daniele Cortis et al. / Procedia Structural Integrity 83 (2026) 3–13

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Electron Microscope (SEM). Hence, the paper is organized as follows: Sect. 2 “ Materials and methods ”, where the tensile test pieces production and the tensile test setup is described; Sect. 3 “ Results and discussion ”, where the results are presented and discussed; Sect. 4 “ Conclusions ”.

2. Materials and methods 2.1. Tensile test pieces production

StrengthAl was produced by means a standard PBF-LB system (i.e., PRIMA Print Sharp 150). The machine offers full-open configuration of process parameters, particularly suitable for research and development activities. The process parameters were optimized to achieve a high relative density ( ρ ) starting from previous work of the authors [Cortis et al. (2022), Cortis et al. (2025)]. The optimal Volumetric Energy Density (VED), applied on the powder bed (equation 1), is reported in Table 2 together with the inert gas, Oxygen (O 2 ) level, scanning strategy, P, S, H and L values. The material density estimation was done on dedicated cubic samples by an analytical balance (i.e., Kern ABS 80-4N) with distilled water at room temperature ( ρ = 9.9777 g/cm 3 at 22 °C) by means of Archimedes’ principle. ܸ ܦܧ ൌ ൗ ሺ1ሻ Table 2. StrengthAl optimal process parameters for PRIMA Print Sharp 150 machine. Parameter Description Laser power (P) 275 W Scanning speed (S) 800 mm/s Hatch distance (H) 70 μ m Layer thickness (L) 40 μ m Inert gas flow rate Argon (Ar) @ 3.0 m/s Oxygen (O 2 ) level < 0.1 % Scanning strategy Meander, with 67° rotation on each layer VED 122.8 J/mm 3 Relative density ( ρ ) 99.3 % Two geometries of test piece were produced according to the requirements of the EN ISO 6892-1 (2020) standard, Annex D. The first has a round cross-section and shoulder-ends without thread; it was used for the evaluation of the YS, UTS and A up to rupture (Fig. 1). The second has flat cross-section and it was employed for the estimation of the E and ν in the elastic regime (Fig. 2). The geometries were selected to optimize low and high-temperature testing operation and the accuracy of the results, as will be describe in the next section. For each test at different temperatures, three round cross-section test pieces were produced, for a total of twelve; while for the elastic regime tests, two flat cross-section test pieces were realized: one for the test at -100 °C and +22 °C (i.e., room temperature), and another one for +100 °C and +200 °C (Table 4). The reason is that a different elastic behavior is expected between these two sets of temperatures. During the production, both types of test pieces were randomly placed on the building platform. They were manufactured vertically (i.e., with the longitudinal axis aligned with the building direction) without any angle of inclination, and with support structures only on the lower surfaces (Fig. 3).