Decrease of Electrical Conductivity Activation Energy of Co-coated AISI 430 Alloy for the Application of SOFCs

Document Type : Research Paper

Abstract

The application of conductive coatings on ferritic stainless steel can decrease electrical conductivity. The
aim of this research was to investigate the electrical conductivity of cobalt coated AISI 430 ferritic stainless
steel by pack cementation technique. Coated coupons were analyzed using scanning electron microscopy
(SEM). Electrical conductivity of the coated substrates was measured as a function of temperature by
oxidizing the samples from room temperature to 700 ºC. Also electrical conductivity has been measured
as a function of oxidation time during isothermal oxidation at 700 ºC. Results showed the increase of
temperature caused to the decrease of electrical conductivity and also, the coating layer converted to cobalt
spinels during annealing in isothermal oxidation. The formation of MnCo2O4, CoCr2O4, CoFe2O4 and Co3O4
spinels improved electrical conductivity activation energy of coated substrates (0.03 eV) compared to
uncoated substrates (0.039 eV).

Keywords

• Cobalt
• AISI 430
• Electrical conductivity activation energy
• Solid oxide fuel cell

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