Achieving high-temperature corrosion resistance and conductivity of SUS430 by xCr-MnCo dual-structured coating

The xCr-MnCo dual-structured coating was proposed on SUS430 steel to achieve high corrosion resistance and conductivity. The results show that Cr barrier layer (x) thickness significantly affect coating performance. Slightly increasing the Cr2O3 thickness will not only enhance the coating corrosion resistance (Kp =2.23 × 10−14 g2·cm−4 s−1) but also improve the conductivity by allowing moderate amount of Fe diffuse into the Mn-Co spinel. However, further increasing the Cr2O3 thickness will increase coating spallation risks due to the thermal expansion coefficients mismatch between Cr2O3, SiO2 and substrate. Finally, 0.03Cr-MnCo coating achieved an optimized balance on corrosion resistance and conductivity.