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[en] Highlights: • The influence of α-Fe_2O_3 on nucleation of α-Al_2O_3 was investigated. • Stable α-Al_2O_3 was formed by direct nucleation at 700 °C. • Minor quantities of θ-Al_2O_3 detected by XRD and TEM in early stages of oxidation. • Changes in chemical composition of α-Fe_2O_3 were followed by Raman spectroscopy. • Nucleation of α-Al_2O_3 instead of metastable Al_2O_3 attributed to template effect. - Abstract: The role of thermally grown α-Fe_2O_3 on the nucleation of α-Al_2O_3 during oxidation of binary Fe–Al alloys with 15 and 26 at.%Al at 700 °C was investigated. Surface morphology of the oxide scales indicated direct nucleation of α-Al_2O_3 preferentially instead of conversion from metastable Al_2O_3 polymorphs. Oxide scale development over time was also monitored by use of synchrotron X-ray diffraction and Raman spectroscopy. The results showed that the α-Fe_2O_3 crystal lattice decreases in volume as oxidation progresses, which was found to be consistent with an Al"3"+ enrichment of α-Fe_2O_3 as confirmed by the change in relative intensity of α-Fe_2O_3 Raman peaks.