Microstructure and Tribocorrosion Properties of Fe3Si Coating Prepared by Molten Salt Infiltration Method

The Fe3Si coating was prepared on the 0Cr18Ni9 stainless steel substrate using a molten salt infiltration method. The microstructure and tribocorrosion properties of Fe3Si coating were investigated in 3.5 wt % NaCl solution. The results showed that the Fe3Si coating was compact and had a good interface binding with the 0Cr18Ni9 substrate, exhibiting a high microhardness (693 HV) compared to the 0Cr18Ni9 substrate (167 HV). Fe3Si coating has better tribocorrosion resistance than 0Cr18Ni9 substrate in NaCl solution with a high open circuit potential (OCP), low current density and wear volume. As the friction coefficient increases, the OCP value of the Fe3Si coating decreases and the current density increases, indicating a strong synergistic effect of wear and corrosion. The Fe3Si coating exhibits good tribocorrosion characteristics due to the formation of a Fe2O3–SiO2 passivation film with good corrosion resistance and lubricating properties.