Correlated extended X-ray absorption fine structure and transmission electron microscopy studies the microstructure of low friction Ti–C–N films

• A series of Ti–C–N films were deposited by magnetron sputtering.
• TEM examination indicates the presence of nanocrystalline phase embedded in an amorphous matrix.
• Lattice fringes of approximately 2.5 Ǻ are observed for some particles.
• EXAFS oscillation curves of Ti–C–N films have a similar shape to that of TiN film.
• Small Ti–C or Ti–N clusters without long-range crystalline order.

The microstructures of Ti–C–N films were investigated by extended X-ray absorption fine structure and transmission electron microscopy. The expected Ti-containing phases, TiN, are not formed in low Ti content film. The local structure around the central Ti atoms as deduced from EXAFS shows the Ti atoms mainly to be situated in disordered regions, possibly small Ti–C or Ti–N clusters without long-range crystalline order. With increasing the Ti content, the film alters the coherent interfaces and forms a nanocomposite structure. Our results indicated increased Ti co-ordination shell disorder in Ti–C–N coatings with decreasing Ti composition. Wear rate and friction coefficient of films decrease as the Ti composition increases.