High Temperature Oxidation of AlCrFe Complex Metallic Alloys

Isothermal oxidation of Al65Cr27Fe8 and Al80Cr15Fe5 was studied in the 600-1080 degrees C range. Formation of transient alumina layers is obtained up to 900 degrees C. On Al65Cr27Fe8 transient to alpha-phase transformations occur when performing oxidation at 1000 degrees C, together with the possible appearance of (Al0.9Cr0.1)(2)O-3. At 1080 degrees C, direct formation of alpha-alumina is obtained. On Al80Cr15Fe5, spallation of the oxide layer during the cooling stage is observed following oxidation at 800 and 900 degrees C, revealing thermal etching of the underneath alloy surface. At 1050 degrees C the alpha-Al2O3 scale is directly formed but plastic deformation and recrystallization of the underneath alloy into several intermetallic phases is observed. (C) 2014 Elsevier Ltd, All rights reserved.