Structure and tribological properties of TiSiCN coating on Ti6Al4V by arc ion plating

Highlights: • The TiSiCN coatings were deposited on Ti6Al4V alloy by arc ion plating. • The coupled structure of TiCN nanocrystal and amorphous phase was fabricated. • The coatings have a super high hardness of 43.6 GPa and low friction coefficient. • The TiCN phase contributes to significant improvement of wear resistance. - Abstract: The TiSiCN coating was fabricated on Ti6Al4V alloy by arc ion plating. The structure of the TiSiCN coating was characterized using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy. The hardness and tribological properties of the TiSiCN coating were evaluated by nanoindentation and ball-on-plate wear tests. The coating has a coupled structure of the TiCN nanocrystal and amorphous phase (Si₃N₄ and SiC). The TiSiCN coating has a super high hardness of 43.6 GPa and modulus of 422 GPa. The values of H/E and H₃/E₂ are 0.103 to 0.465, respectively. The coating has a low friction coefficient of 0.3, and the wear loss is 1.76 × 10⁻⁶ mm³/Nm, which is only 1/3 of the wear loss of the TiSiN coating. The TiCN phase contributes to significantly decrease the friction coefficient and wear rate of the TiSiCN coating.