Influence of the nitrogen content on the corrosion resistances of multicomponent AlCrNbYZrN coatings

In this study, the relationship between the nitrogen content and the corrosion resistances of non-equimolar multicomponent AlCrNbYZrN films (N = 13–49 at.%) is probed. While there was no linear relationship between nitrogen content and corrosion resistance, the results clearly show that the corrosion resistances of the films were instead determined by their nitrogen-induced porosities i.e. the less porous the sample, the higher the corrosion resistance. The 23, 30 and 37 at.% N samples were denser while the 13 at.% N sample was porous and the 49 at.% N film had an underdense nanocrystalline columnar cross section permitting the ingress of electrolyte.