Thermal expansion coefficients of alpha alumina films formed by oxidation of an oxide dispersion strengthened (ODS) FeCrAl alloy have been determined between 20 and 900 degrees C 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 alpha alumina film is found to equal 10.3 x 10(-6) K-1 which is higher than most values given in the literature. (c) 2005 Elsevier B.V. All rights reserved.