Thermal expansion coefficient of alumina films developed by oxidation of a FeCrAl alloy determined by a deflection technique

Thermal expansion coefficients of a alumina films formed by oxidation of an oxide dispersion strengthened (ODS) FeCrAl alloy have been determined between 20 and 900 8C using an original deflection test. This technique is based on the curvature of a dissymmetrical sample consisting of a thin and elongated metallic substrate covered on one of its large sides by an oxide film. The average value of the expansion coefficient of the compact columnar a alumina film is found to equal 10.3 10 6 K 1 which is higher than most values given in the literature.