The Effect of Metallic Co-Coating Thickness on Ferritic Stainless Steels Intended for Use as Interconnect Material in Intermediate Temperature Solid Oxide Fuel Cells

• Published in: Oxidation of metals Vol. 89; no. 1-2; pp. 233 - 250
• Main Authors: Falk-Windisch, Hannes, Claquesin, Julien, Svensson, Jan-Erik, Froitzheim, Jan
• Format: Journal Article
• Language: English
• Published: New York Springer US 2018; Springer Nature B.V
• Subjects: Area-specific resistance; Chemistry and Materials Science; Coating; Coating effects; Cobalt; Corrosion; Corrosion and Coatings; Electron microscopy; Ferritic stainless steels; Inorganic Chemistry; Interconnect; Materials Science; Metallic Materials; Original Paper; Oxidation resistance; Reaction kinetics; Scale (corrosion); Solid oxide fuel cell; Solid oxide fuel cells; Stainless steel; Thickness; Tribology; X ray analysis; Interconnect; Coating; Corrosion; Area-specific resistance; Solid oxide fuel cell
• ISSN: 0030-770X; 1573-4889; 1573-4889
• DOI: 10.1007/s11085-017-9782-9

The effect of metallic Co-coating thickness on ferritic stainless steels is investigated. This material is suggested to be used as interconnect material in intermediate temperature solid oxide fuel cells. Uncoated, 200-, 600-, 1000-, and 1500-nm Co-coated Sanergy HT is isothermally exposed for up to 500 h in air at 650 °C. Mass gain is recorded to follow oxidation kinetics, and area-specific resistance (ASR) measurements are conducted on samples exposed for 168 and 500 h. The microstructure of the thermally grown oxide scales is characterized utilizing scanning electron microscopy and energy-dispersive X-ray analysis on broad ion beam-milled cross sections. A clear increase in ASR as a function of Co-coating thickness is observed. However, the increase in ASR, as an effect of a thicker Co-coating, is correlated with thicker (Cr,Fe) 2 O 3 scales formed on these materials and not to an increase in Co spinel top layer thickness.