PSI - Issue 75

Monisha Manjunatha et al. / Procedia Structural Integrity 75 (2025) 650–659 Monisha Manjunatha et al. / Structural Integrity Procedia (2025)

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The chemical composition analysis of the tested materials was conducted using Spark Optical Emission Spectroscopy (Spark OES). To evaluate the mechanical properties, tensile testing was performed in accordance with ASTM E8 at room temperature using Instron 8801 servo-hydraulic fatigue testing system, capable of applying forces up to ±100 kN. A displacement rate of 1 mm/min was selected for the tests, with a gauge diameter of 6 mm. Measured material properties are listed in Table 2.

Fig. 1. Micrographs of (a) Grade 1; (b) Grade 2; (c) Q355B; (d) S355JR taken at [x500] Any deviation in elastic properties can lead to inaccurate stress estimations, affecting the reliability of fatigue life predictions. Table 2. Mechanical properties of tested steel. Material Yield Strength (MPa) Tensile Strength (MPa) Elastic Modulus (GPa) Hardness (HV) Charpy Impact toughness (J) Grade 1 844 886 203 313.5 216 Grade 2 572 698 196 219 174 Q355B 424 560 214 174 - S355JR 388 513 218 167 -