A study on the corrosion resistance of ZrN/CrN multilayer nanostructured coating applied on AISI 304 stainless steel using Arc-PVD method in 3.5 wt% NaCl solution

In this research, a ZrN/CrN multilayer nanostructured coating was applied on AISI 304 stainless steel substrate using physical vapor deposition (PVD) in type of cathodic arc evaporation (CAE). The microstructure evaluation of the specimens were analyzed by x-ray diffraction and scanning electron microscopy. Impedance spectroscopy tests were utilized to evaluate the corrosion behavior of ZrN/CrN multilayer nanostructured coating and the substrate in 3.5 wt% NaCl solution. Applying CAE technique, ZrN/CrN multilayer nanostructured coating having high density and adhesion was successfully made. The corrosion results revealed that ZrN/CrN multilayer nanostructured coatings had an exceptionally high polarization resistance compared to AISI 304 stainless steel substrate. Moreover, the corrosion results showed the desired corrosion behavior in the ZrN/CrN multilayer nanostructured coating towards the AISI 304 substrate within the 3.5 wt% NaCl solution due to the presence of distinct layer resulting in a barrier against penetration of the corrosive solution. Scanning electron microscopy micrographs revealed that the surface of the ZrN/CrN multilayer coating is free of pits or any serious damage.