Improving the Oxidation Resistance and Electrical Properties of Ferritic Stainless Steels for Application in SOFC Interconnects

Abstract

The paper presents the results of cyclic oxidation studies performed for two ferritic stainless steels: Crofer 22 APU and H25T. The surface of the steels was coated with particles of oxides of the following active elements: yttrium, cerium, samarium, and gadolinium. Two coating methods were used: electrolysis and dip-coating. In addition, yttrium ion implantation was carried out for the purpose of reference. Cyclic oxidation tests were carried out for ca. 1200 h in air at 900 °C. It was determined that particles of oxides of active elements reduce the rate of oxidation, improve the adhesion of the Cr2O3 scale to the substrate, and decrease area specific resistance.