Oxidation behaviour of Fe-Cr-AI alloys during resistance and furnace heating

Oxidation behaviour of Fe-Cr-AI alloys during resistance and furnace heating 

Because of their excellent oxidation resistance, Fe-Cr-Al alloys are commonly used construction materials for components that have to operate at high temperature. The oxidation resistance relies on the formation of slowly growing, well adherent alumina-based surface oxide scales, which form during high temperature exposure. Examples of the application of Fe-Cr-Al alloys are heating element strips or wires, fibre-based domestic and industrial burners, car catalyst carriers, furnace tubes, etc. 

The commercial Fe-Cr-Al alloys studied were the wrought alloys Aluchrom 

Y and Aluchrom YHf with the nominal composition of Fe-20Cr-5.5Al (wt.%). Both alloys contained minor additions in the range of a few hundred ppm of 

Y and Zr. Furthermore, alloy Aluchrom Y contained minor additions of Ti, whereas in Aluchrom YHf small amounts of Hf were present. The alloys were manufactured by conventional metallurgical methods (casting followed by hot and cold rolling). The width of the strips was 5 mm and the foil thickness varied between 30 p.m and 100 p.m, although most of the experiments were carried out using 50 p.m thick foils. 

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