Electrophoretic deposition of MnCr2O4 coating for solid oxide fuel cell metallic interconnects

In the present study, Mn - Cr spinel powder was synthesized through a solid state reaction. In the next step, the electrophoretic deposition (EPD) method was used to apply the MnCr2O4 spinel, as an oxidation-resistant layer, on SUS 430 stainless steel in a potential of 300 V/cm. The coated and uncoated samples were then pre-sintered in air at 900 °C for 3 h followed by cyclic oxidation at 800 °C for 500 h. In order to study the effect of reducing pre-sintering atmosphere on oxidation resistance, the coated specimen was pre-sintered in 5% H2 / Ar at 900 °C for 3 h followed by cyclic oxidation at 800 °C for 500 h. The investigation of the oxidation resistance of the samples revealed that the MnCr2O4 spinel coating improved the oxidation resistance of the uncoated sample and also, the oxidation rate constant (Kp) for pre-sintered coating in 5% H2 / Ar was nearly 14 times smaller than that of the one pre-sintered in air.