Investigation of Electrical Conductivity of AISI 430 Steel at Presence of Mn Spinel Compositions

The electrical conductivity of AISI 430 ferritic stainless steel which is used as an interconnect in solid oxide fuel cells (SOFCs) for intermediate temperature operation, can be improved with a conductive coating layer. In this study, AISI 430 ferritic stainless steel was coated in a Mn-base pack mixture by pack cementation method. As-coated specimens were characterized using scanning electron microscopy (SEM).Electrical conductivity of the coated coupons was tested as a function of temperature by oxidizing the samples from room temperature to 700 ºC. Also electrical conductivity has been evaluated 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 transformed to manganese spinels during isothermal oxidation. Spinels ameliorated the electrical conductivity of coated coupons (69 S.cm-1) compared to uncoated ones (32 S.cm-1) after 200 h oxidation at 700 ºC

Keywords:

Manganese spinel , Electrical conductivity , AISI 430 ferritic stainless steel