PSI - Issue 68

Shahriar Afkhami et al. / Procedia Structural Integrity 68 (2025) 929–935 S. Afkhami et al. / Structural Integrity Procedia 00 (2025) 000–000

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fractography observations are in agreement with defect and surface quality analysis, as shown in Fig. 7. According to this figure, the failure in the Al5X1 component initiated from a surface protrusion, although the presence of porosity clusters near the surface is also significant. The Ti64 components mainly failed from a surface valley, regardless of its condition (as-built or shot balsted). Surface inhomogeneities also initiated the failure of the 316L components; however, compared to the components made of Al5X1 and Ti64, the severity of 316L’s surface inconsistencies was more moderate, which seemingly contributed to relatively better fatigue performance of the component made of 316L, compared to Al5X1 and Ti64, although the strength of 316L is significantly inferior to Ti64’s.

Fig. 5. Fatigue test results according to the (left) global applied load values and (b) local stress values calculated and corrected via FEA.

Fig. 6. Overall view and low-magnification fractography of the components

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Fig. 7. Fractography images taken from the failure sites.