PSI - Issue 57

24 Mathilde Renault et al. / Procedia Structural Integrity 57 (2024) 22–31 Mathilde RENAULT / Structural Integrity Procedia 00 (2019) 000 – 000 3 The roughness indicators are calculated in the z direction of deposition and in the transverse direction for the 2D indicators. The 2D indicators of arithmetic mean height and maximum height of the profiles / surfaces are calculated as follows = 1 ∑ | | 1 ; = 15 (∑ 5 1 − ∑ 5 1 ) Eq 1 The values obtained are summarized in table 2. Table 2 : Roughness parameters in transversale direction (x) and longitudinal direction (y) ̅̅̅̅ ( ) ̅̅̅̅ ( ) ̅̅̅̅ ( ) ̅̅̅̅ ( ) 171 236 515 565 2.2. Test specimens The test specimens are 200 mm x 40 mm x 15 mm parallelepipeds extracted by electrical discharge machining from the raw blocks of WAAM deposits as illustrated in Figure2. Two flat zones were machined for the bending rollers to lie on. The edges of the specimens were milled to prevent cracks from initiating on the edges (which is not representative of the behavior of raw parts).

Figure2 : Geometry of test specimens (all dimensions in mm)

Taking into account the surface roughness, the nominal thickness of the samples is chosen such as = − 2 ≈ 14.75 Eq 2