THE OXIDATION BEHAVIOR OF ODS IRON ALUMINIDES

Oxide-dispersed Fe-28at.%Al-2%Cr alloys were produced by a powder meta llurgy technique followed by hot extrusion. A variety of stable oxides were added to the base alloy to assess the effect of these dopants on the oxidation behavior at 1200 degrees C in air and O-2. An AL(2)O(3) dispersion flattened the alpha-AL(2)O(3) scale, but produced none of the other reactive element effects and had an adverse influence on the long-term oxidation behavior. A Y2O3 dispersion improved the alumina scale adhesion relative to a Zr alloy addition at 1200 and 1300 degree s C. However, the Y2O3 dispersion was not as effective in improving sc ale adhesion in Fe3Al as it is in FeCrAl. This inferior performance is attributed to a larger amount of interfacial void formation on ODS Fe 3Al.