Oxidation processes in vanadium-based single-layer and nanolayer hard coatings

The analysis of the oxidation mechanisms for all three types of coatings showed that the formation of a thin chromium oxide layer slows down the diffusion of vanadium towards the surface. However, at the locations where the growth defects were present the vanadium kept diffusing at high rates and formed V2O5 dendritic structures at the surface. Vanadium oxide is known to have good lubricating properties at elevated temperatures, thus (Cr,V)N-based hard coatings could potentially be useful for the protection of hot-forging tools operating at high temperatures.