PSI - Issue 59

Sviatoslav Motrunich et al. / Procedia Structural Integrity 59 (2024) 58–65 Sviatoslav Motrunich et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 7. Fatigue fracture of the Specimen #1 (a, d, j, g) tested at 2S a = 800 MPa and failure at N f = 2579 cycles, Specimen #2 (b, e, h, k) – 2S a = 600 MPa, N f = 77365 cycles, Specimen #3 (c, f, i, l) – 2S a = 500 MPa, N f = 1283604 cycles: (a,b,c) general view of the fractured surface (diameter 5mm); (d, e, f) fatigue crack initiation zone, (g, h, i) fatigue crack propagation zone, (j, k, l) brittle fracture.