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

The application of conductive coatings on ferritic stainless steel can decrease electrical conductivity. Theaim of this research was to investigate the electrical conductivity of cobalt coated AISI 430 ferritic stainlesssteel 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 byoxidizing the samples from room temperature to 700 ºC. Also electrical conductivity has been measuredas a function of oxidation time during isothermal oxidation at 700 ºC. Results showed the increase oftemperature caused to the decrease of electrical conductivity and also, the coating layer converted to cobaltspinels during annealing in isothermal oxidation. The formation of MnCo2O4, CoCr2O4, CoFe2O4 and Co3O4spinels improved electrical conductivity activation energy of coated substrates (0.03 eV) compared touncoated substrates (0.039 eV).