Manganese Spinel Coatings to Reduce Electrical Conductivity Activation Energy of Interconnects

Stainless steel can be used as interconnects plate in solid oxide fuel cells (SOFC)for operating temperature of 800 ºC or below. Unwanted reactions between the alloy and other SOFC components decrease the efficiency of these energy convertors. One approach to improve interconnect properties is to apply surface coating. In this research, AISI 430 ferritic stainless steel was coated in a Mn-base pack mixture by pack cementation method. Electrical conductivity of the coated coupons was measured as a function of temperature by oxidizing the samples from room temperature to 800 ºC. Also the electrical conductivity has been studied as a function of oxidation time during isothermal oxidation at 800 ºC. Results showed the increase of temperature caused to the decrease of electrical conductivity and also, the coating layer transformed to manganese spinels during isothermal oxidation. The spinel compositions ameliorated the electrical conductivity activation energy of coated coupons (0.029 eV) compared to uncoated ones (0.031 eV).

کلیدواژه ها:

Manganese ، Solid oxide fuel cell (SOFC) ، Spinel ، Electrical conductivity activation energy ، Interconnect