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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EBSD Electron backscattered diffraction EDS Energy dispersive spectroscopy FCC Face centered cubic FeAlOY ODS steel with chemical composition Fe-10Al-4Cr- 4Y₂O₃ GB Grain boundary KAM Kernel Average Misorientation ODS Oxide dispersion strengthened PSB Persistent slip bands PSM Persistent slip markings SEM Scanning electron microscopy STEM Scanning transmission electron microscopy

*Corresponding author. E-mail address: vrazina@ipm.cz

2. Materials and methods Two distinct materials were selected to represent different crystallographic systems: Sanicro 25 as an FCC alloy and FeAlOY with BCC crystal structure. Their chemical compositions are summarized in Table 1. Sanicro 25, a high performance super-austenitic stainless steel, was supplied by Sandvik AB in the form of large- diameter rods (150 mm) that underwent a solution annealing treatment at 1200 °C for 1 hour , followed by air cooling. The rods were later machined into cylindrical samples as illustrated in Fig. 1(a). The FeAlOY was fabricated via a multistep route comprising mechanical alloying, thermomechanical consolidation. Initially, high-purity elemental powders of Fe, Al, and Cr (Table 1) were blended with Y₂O₃ (3 wt.%) and elemental Y (1 wt.%) homogenization up to atomic level. The mechanically alloyed powder was sealed in a steel container lined with corundum to prevent interaction during processing and then subjected to hot rolling in multiple stages. The initial consolidation involved 5 rolling passes at 800 °C, followed by 3 additional passes at 1000 °C to enhance microstructural homogenization. To induce secondary recrystallization and due to abnormal grain growth, a final annealing treatment was performed at 1200 °C for 2 hours. Particular details of the FeAlOY alloy manufacturing process can be found in the work of Gamanov (Gamanov et al., 2023) The resulting bulk material was obtained as flat plates with dimensions of approximately 15 0 × 5 × 5 mm . Specimens (Fig. 1(b)) were cut by electrical discharge machining and ground to a P4000 finish and electrolytically polished prior to testing.