Reduced electrical resistance of interconnects at presence of Mn₃O₄ and MnFe₂O₄

The aim of this work was to investigate the electrical behavior of AISI 430 ferritic stainless steel which was coated in a Mn-base pack mixture by pack cementation method. Area-specific resistance (ASR) of the coated substrates was tested as a function of temperature by annealing the samples from room temperature to 700°C. Also ASR has been investigated as a function of oxidation time during isothermal oxidation at 700°C. Results showed the increase of temperature redounded to the higher values of ASR and also, the coating layer transformed to Mn₃O₄ and MnFe₂O₄ spinels during annealing in isothermal oxidation. These spinels caused to decrease the ASR values for coated substrates (14.38 mΩcm2) compared to uncoated substrates (31.25 mΩcm2) after 200 h isothermal oxidation.