PSI - Issue 7

Ana D. Brandão et al. / Procedia Structural Integrity 7 (2017) 58–66 Author name / Structural Integrity Procedia 00 (2017) 000–000

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The milled specimens (ID 1 to 6) were printed as bars and then machined to the geometry shown in Fig. 1c. For the net shaped specimens, the surface was either jet blasted (ID 9 to11) with “IEPCONORM_C” (iepco ag), or treated through vibratory polishing (ID 7 and 8), or left in its “as built” condition without surface treatment (ID 12). The heat treatment used in conditions ID 1, 3 and 5 was applied to reduce the residual stresses present in the specimens, which are characteristic of the additive manufacturing process (Tang and Pistorius (2017)).

Fig. 1. Specimens manufacturing conditions, specifically the (a) orientation of manufactured specimens, (b) principle of scanning strategy for a vertically built specimen regarding inner hatch / filling and contour and (c) geometry of fatigue test specimens according to standard ASTM E 466 (2015).

Table 1. Description of parameters combination per test condition.

Parameter ID

Shape milled milled milled milled milled milled

Layer thickness [µm]

Orientation

Post treatment

Heat treatment

1 2 3 4 5 6 7 8 9

90 / build plate heating 35°C

vertical vertical

none none none none none none

300 °, 2h

30 90 90 90 90 30 30 90 90 90

none

horizontal horizontal vertical vertical vertical vertical vertical vertical vertical horizontal

300 °, 2h

none

300 °, 2h

none none none none none none none

net shape net shape net shape net shape net shape net shape

30 / without contour

vibratory polishing vibratory polishing

jet blasted jet blasted jet blasted

10 11 12

none