Surface characterization of titanium nitride composite coatings fabricated by reactive plasma spraying

Composite Ti, TiN, TixNy coatings have been fabricated by reactive plasma spraying (RPS), starting from Ti alloy powders and using Ar/N-2 plasma gas in a NZ atmosphere. Reactively sprayed coatings produced from SP700 (Ti-4.5Al-3V-2Mo-2Fe) and Ti6242 (Ti-6Al-2Sn-4Zr-2Mo) powders, deposited onto flat substrates of Ti6Al4V, have been investigated. XPS and SEM techniques have been used to determine the chemical composition and to characterize the interface between the coatings and substrate. The results obtained show a sharp interface between the coating and substrate in terms of composition profile. The presence of unmelted Ti particles as well as the formation of nitrides was observed.