INTERNAL STRESSES AND TEXTURE OF NANO-STRUCTURED ALUMINA SCALES GROWING ON Fe3Al POLYCRYSTALS
نویسندگان
چکیده
The evolution of internal stresses in oxide scales growing on an Fe3Al polycrystal in atmospheric air at 700 determined using in-situ energy-dispersive synchrotron x-ray diffraction. Texture analyses were performed ex-situ after 5h of oxidation at 700 the oxide scale thickness, as determined by x-ray photoelectron spectroscopy, lays between 80 and 100nm. The main phase present in the oxide scales is -Al2O3, with minor quantities of metastable -Al2O3 detected in the first minutes of oxidation, as well as -Fe2O3. -Al2O3 grows with a weak (0001) fiber texture in the normal direction. During the initial stages of oxidation the scale develops increasing levels of compressive stresses, which later evolve to a steady state condition situated around -300MPa.
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