Study on corrosion properties of TiN-TiAlN-TiAlSiN-TiSiN composite coatings prepared by cathodic arc deposition

A TiN-TiAlN-TiAlSiN-TiSiN composite coating was prepared on the surface of 316L stainless steel using cathodic arc technology. The microstructure of the coating was studied by scanning electron microscope (SEM) and X-ray diffraction (XRD), and its corrosion properties were evaluated through electrochemical measurements. The results revealed that the composite coating primarily consisted of (Ti, Al)N phases and amorphous Si₃N₄. The coating exhibited a columnar growth pattern, with Si addition refining the columnar grains and the dense structure reducing the likelihood of corrosive media penetrating to the substrate. Potentiodynamic polarization curves in 3.5% NaCl and 3.5% HCl solutions showed that the composite coating exhibited lower corrosion current density and passive current density, as well as a higher self-corrosion potential, compared to 316L stainless steel. These findings indicate that the TiN-TiAlN-TiAlSiN-TiSiN composite coating has a lower tendency and rate of corrosion, making it a highly promising corrosion-resistant material.