PSI - Issue 80

Tomáš Vražina et al. / Procedia Structural Integrity 80 (2026) 244 – 255 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 5 Fracture surface morphology of FeAlOY specimens subjected to cyclic loading at various applied strain amplitudes: (a) 0.4%, (b) 0.35%, and (c) 0.32%. Intercrystalline cracking (highlighted in orange). (d – f) Higher magnification views of PSMs at strain amplitudes of (d) 0.4% (e) 0.35%, (f) 0.32%.

Fig. 6 Fracture surface morphology of Sanicro 25 specimens subjected to cyclic loading at various applied strain amplitudes: (a) 0.4%, (b) 0.35%, (c) 0.32%. Intercrystalline cracking (highlighted in orange). (d – f) Higher magnification views of PSMs at strain amplitudes of (d) 0.4% (e) 0.35%, (f) 0.32%. 3.4. STEM observation of dislocation substructure Figure 7(a – c) presents STEM micrographs of the dislocation structure in FeAlOY after cyclic testing, with particular emphasis on PSBs in Fig. 7(a) and their detailed morphology in Fig. 7(b) and (c). Despite the inherently low contrast caused by the dispersion of oxide nanoparticles, distinct PSBs are visible across large grains, confirming localized cyclic plasticity in FeAlOY as also observed at high temperature . In contrast, Fig. 7(d – f) shows STEM