Titanium Oxynitriding by Plasma-Assisted Thermochemical Treatments Using a Competitive Atmosphere of H₂-N₂-O₂

The incorporation of oxygen and/or nitrogen into the titanium lattice has garnered significant attention due to the broad spectrum of intermediate properties that can be achieved between TiN and TiO₂. This article delves into the investigation of surface modification of titanium through plasma-assisted thermochemical treatments employing H₂-N₂-O₂ mixtures. The flow rate of the reducing gas (H₂) remained constant at 24 sccm, while the flow rates of N₂ and O₂ were adjusted to yield a total flow rate of 60 sccm. Analysis using GIXRD, Raman spectroscopy, and XPS demonstrated that TiN exhibits stability exclusively in an oxygen-free atmosphere, while TiO₂, in contrast, necessitates an oxygen flux equal to or exceeding 18 sccm for stability. Furthermore, it was found that the presence of nitrogen in the plasma atmosphere resulted in a greater expansion of the α-titanium lattice, although the solubility of interstitials decreased. These findings highlight the potential for a controlled approach to producing solid solutions or titanium oxynitrides.

Keywords:
Plasma, Thermochemical treatment; Plasma diagnostic; GIXRD; Titanium oxynitride