OXIDATION OF CR94FE5(Y2O3)(1) AT HIGH-TEMPERATURES

The oxidation behaviour of a Cr-rich alloy developed for use in solid oxide fuel cell (SOFC) stacks has been investigated in the temperature range from 850-1600 degrees C in air and in a hydrogen-low oxygen par tial pressure atmosphere. Severe buckling of the scale is observed whe n the alloy is exposed to air at high temperature. The buckling may be detrimental for the expected application areas, such as in SOFC stack s. It is demonstrated that heat treatments in a hydrogen low oxygen pa rtial pressure atmosphere provides a very good adhesion of the formed scale to the underlying metal, even for heat treatments up to 1600 deg rees C. The scale remains well-adhering even after a reoxidation in ai r at 1300 degrees C. Possible reasons for the improved behaviour are d iscussed.