High temperature oxidation of AlCrFe complex metallic alloys

Abstract Isothermal oxidation of Al 65 Cr 27 Fe 8 and Al 80 Cr 15 Fe 5 was studied in the 600–1080 °C range. Formation of transient alumina layers is obtained up to 900 °C. On Al 65 Cr 27 Fe 8 transient to α-phase transformations occur when performing oxidation at 1000 °C, together with the possible appearance of (Al 0.9 Cr 0.1 ) 2 O 3 . At 1080 °C, direct formation of α-alumina is obtained. On Al 80 Cr 15 Fe 5 , spallation of the oxide layer during the cooling stage is observed following oxidation at 800 and 900 °C, revealing thermal etching of the underneath alloy surface. At 1050 °C the α -Al 2 O 3 scale is directly formed but plastic deformation and recrystallization of the underneath alloy into several intermetallic phases is observed.