Study by deflection of the influence of alloy composition on the development of stresses during alumina scale growth

According to the nature and amount of their impurities or doping elements and to their fabrication mode, the creep properties and the oxidation behavior of alumina forming iron-based alloys, can largely vary. The objective of this work was to study, by means of deflection tests based on the curvature of a dissymmetrical sample, the stress development during alumina growth with an attempt to determine the parameters which are responsible for the observed curvature during oxidation. Three different FeCrAl alloys were chosen and subjected to oxidation cycles in argon or air, in most cases at 1000 °C. The results were compared to those obtained on a previously studied Fe3Al intermetallic alloy, and analysed on the basis of literature data and microstructural observations.