Experimental data for electrophoretic co-deposition of CuO–Mn₂O₃ nanopowders

Cu–Mn spinel coatings were produced on ferritic steel substrates via electrophoretic deposition (EPD) of CuO and Mn₂O₃ nanopowders, followed by a two-stage thermal treatment process involving reduction in Ar–H₂ and reoxidation in air. The effect of processing temperature on the microstructure, phase composition, oxidation resistance, and electrical performance was systematically examined. Higher reduction temperatures (≥900 °C) resulted in the development of dense, continuous coatings with improved barrier properties, whereas lower temperatures increased porosity and facilitated chromium diffusion. XRD analysis confirmed the formation of a stable (Cu,Mn,Cr)₃O₄ spinel phase, ensuring good interfacial stability after long-term oxidation. All coatings reduced high-temperature oxidation compared to bare steel and maintained area-specific resistance below 0.1 Ω·cm² after 3000 hours at 750 °C. The findings indicate that nanopowder-based EPD allows for the fabrication of Cu–Mn spinel coatings at lower temperatures (850–900 °C), providing an energy-efficient and scalable approach for SOFC/SOEC interconnect protection.