PSI - Issue 54

R.F. Fernandes et al. / Procedia Structural Integrity 54 (2024) 300–306 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

302

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2. Experimental procedures A Renishaw machine (model AM 400) was used to produce the fatigue specimens by utilizing the Laser Powder Bed Fusion process. The machine operated at a maximum laser power of 350 W, scanning speed of 1.8 m/s, and layer thickness of 30 µm. The feedstock material was prepared according to the DIN 1706 standard (2021) and its composition is presented in Table 1.

Table 1. Chemical composition of the AlSI10Mg (%wt) (DIN 1706, 2021). Al Si Mg Mn Cu Ni Fe Zn

Pb

Sn

Ti

Bal.

09-11

0.25-0.45

0.45 0.05

0.05

0.55

0.10

0.05

0.05

0.15

The geometry of the specimens is illustrated in Figure 1. The specimens were manufactured in the vertical direction, with the layers deposited perpendicular to the loading direction. The fatigue tests were performed at room temperature using a computer-controlled 100 kN DARTEC servo-hydraulic machine, under load control mode for R=0 at a frequency of 10 Hz with a sinusoidal wave.

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BUILDING DIRECTION

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Fig. 1. Specimens Geometry: a) Unnotched specimen, b) D – Semicircular notch and c) O – Hole notch

In addition, the objective of this study was to investigate the notch effect on fatigue behavior. To achieve this, two different notch geometries were introduced: a semicircular notch (D) around the surface, and a through-hole (O) at the center of the specimen, as illustrated in Figure 1b) and 1c), respectively. Two different heat treatments were applied to minimize the residual stresses: Stress relief with a temperature of 250 ºC for 2 h followed by water quenching and Hot isostatic pressing at the same temperature, followed by cooling to room temperature.