High Temperature Oxidation of Fe22Cr-alloy

Research paper by L. Mikkelsen, P. H. Larsen, S. Linderoth

Indexed on: 01 Jun '01Published on: 01 Jun '01Published in: Journal of Thermal Analysis and Calorimetry


The isothermal and constant heating rate oxidation behaviour of the alloy Fe78Cr22 was examined in air with 1% H2O and in 7% H2/93% Ar with 1% or 12% H2O. The measurements were performed in the temperature range 700–1300°C. The effect of surface treatment prior to oxidation was examined. A Cr2O3 scale developed slowly up to900°C. At 1100°C a catastrophic oxidation was observed after heat treatment for 70 h in air with 1% H2O and in 7% H2/93% Ar with 12% H2O. The scale developed in these cases consisted of iron rich oxides such as Fe2O3 or FeCr2O4, in contrast to the more protective Cr2O3 scale seen under other test conditions. Possible causes for the catastrophic oxidation are discussed.