Surface Texture, Wettability and Tribological Behavior of Titanium Nitride-Based Coatings Deposited on Ti6Al4V Titanium Alloy

This study presents an analysis of two titanium nitride-based coatings, TiCN and TiN:Ag, deposited on Ti6Al4V alloy by physical vapour deposition (PVD). The investigation focused on the characterisation of surface geometric structure and wettability, tribological parameters, and osseointegration. The purpose of the study was to obtain a better understanding of the interactions between the implant surface and the surrounding tissues and body fluids, which are essential for ensuring long-term durability. The results revealed significant differences in surface stereometric parameters between the coatings, with TiN:Ag exhibiting higher roughness values. These variations were reflected in the wettability tests, where the coating with a more developed surface topography (TiN:Ag) demonstrated contact angle values approximately 15% higher than those of TiCN. In contrast, tribological tests indicated superior performance of the TiCN coating, which exhibited lower coefficients of friction in artificial saliva at pH 5.8 and 6.8-reduced by 20% and 36%, respectively, compared with TiN:Ag. The findings confirmed that surface topography exerts a decisive influence on both wettability and tribological behaviour of the coatings, aspects that must be considered in their design for implantological applications.