Microstructure, Wear Resistance and Corrosion Resistance of CrN Coating with Platinum-Iridium Co-Doping

A novel Pt-Ir co-doping strategy was devised to enhance the corrosion resistance of CrN coating. The deposited CrN coating exhibits a coherent growth pattern, resulting in significant mechanical strength and large grain sizes. However, during the corrosion process, corrosive fluids infiltrate through growth defects, leading to inadequate corrosion resistance of the coating. By incorporating Pt-Ir atoms as dopants, coherent grain growth is effectively hindered, yielding a uniformly smooth surface. Simultaneously, localized non-coherent lattice growth occurs due to co-doping in the coatings, impacting the mechanical properties of CrN-PtIr coatings and causing multidirectional fracture. Nevertheless, this dense coating surface impedes the penetration of corrosive fluids and enhances the corrosion resistance of the coating to some extent.