THERMAL EXPANSION CHARACTERISTICS AND CORROSION BEHAVIOUR OF FERRITIC STEELS FOR SOFC INTERCONNECTS

摘要

In the present paper the thermal expansion characteristics (TEC) of FeCr (Al/Ni) model alloys as well as the oxidation behaviour of high chromium ferritic steels have been studied. In ferritic alloys an increase of chromium content decreases TEC. Aluminium addition leads to an increase of TEC whereas the effect of Ni is correlated with the α/γ-tranformation. The oxidation resistance of high Cr ferritic steels at 700-900℃ strongly depends on the presence of minor alloying additions. As some of these materials are "borderline" alloys between protective and non-protective behaviour, surface preparation and component geometry are important factors to be considered in respect to oxidation resistance.