Tribological behavior of TiN and Ti (Si,C)N coatings on cold sprayed Ti substrates

The evolution of the cold spray technology in the aerospace part repair created a need to better understand the mechanical and tribological behavior of the protective coatings on the cold sprayed repair. For that purpose, a bi-layer system consisting of titanium cold spray coating on a commercially available titanium substrate and TiN, TiSiN and TiSiCN HiPIMS protective coatings were produced. The mechanical and tribological behavior of the coatings was evaluated under reciprocating wear with a reciprocating tribometer equipped with an aluminum ball (4 mm in diameter) counterface. The wear tracks were analyzed with a light interferometer. A cross-sectional analysis of the wear track was performed with SEM following focused ion beam milling. Focused ion beam milling revealed the deformation induced damages to the coatings. Cold sprayed substrate porosity, grain refinement and hardness were shown to play a significant role on the wear characteristics of HiPIMS deposited TiN, TiSiN and TiSiCN coatings.