In situ synthesized TiC–DLC nanocomposite coatings on titanium surface in acetylene ambient

•TiC–DLC coating was in situ synthesized by target poisoning technology.•Nanoscale TiC particles and DLC phases were formed.•Structure and composition were affected greatly by C2H2 flow rate.•Thickness and CC bonds were affected by C2H2 flow rate and synthetic time. TiC–DLC coatings were in situ synthesized on Ti target surface in acetylene ambient by cathodic arc evaporation. In this process, TiC–DLC composite phases were formed by chemical reaction between Ti target surface and ionized C ions. Different acetylene (C2H2) flow rate and synthetic time were designed as two independent variables to synthesize two series of coatings to study the effects of different synthetic parameters on structure of the coatings. Surface morphology, composition and structure of the coatings were investigated by SEM, EDS, XRD and Raman spectroscopy, respectively. The result showed that the structure and composition of the coatings on the titanium metal target surface could be controlled by changing the C2H2 flow rate. The uniform TiC-DLC composite phases were observed in the coatings, while both C2H2 flow rate and synthetic time could significantly affect the thickness and bonding state of the coatings.