PSI - Issue 75

Carolina Payares-Asprino et al. / Procedia Structural Integrity 75 (2025) 489–500 C. Payares-Asprino et al./ Structural Integrity Procedia (2025)

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a)

b)

Fig. 4 a) Schematic drawing of the robotic bead on plate (BOP) weld; b) schematic drawing of machining weld bead.

Fig.5 Flat axial fatigue specimens, dimension in mm.

The test specimens were placed between the Zwick-Roell® HB 100 testing machine knurled grips (Figure 6). Axial fatigue experimental tests were carried out on a total of five transverse to rolling direction DSS butt weld specimens with a thickness of 6.25 mm. The stress levels in (MPa) were 550, 450, 350, 250, and 150 by means of stress ratio of R =σ min /σ max = 0, a frequency of 20Hz, and a sinusoidal stress wave. The maximum level of the cycle was 3 million. Then, the S – N curves were built by using uniaxial tensile data obtained by this procedure. DSS weld fatigue specimens manufactured in HAAS CNC milling machine with weld bead and with the weld bead removed are presented in Figures 7a and 7b, respectively. The number of fatigue specimens tested was three for each stress level and for each welding condition, giving a total of ninety (90) specimens: 45 for the welds with the weld bead and 45 for the machined welds.

Fig.6 Fatigue testing equipment