Influences of bias voltage on properties of TiAl-doped DLC coatings synthesized by cathodic arc evaporation

In this work, the combinations of TiAl-doped DLC (Diamond-like Carbon) and TiAlN/TiN double-layered films were designed to deposit on the tool steels using cathodic arc evaporation in a single process. The economic advantage in depositing the combined coating in one production scale PVD coating system is of practical importance. The TiAl-doped DLC as lubricant coatings were synthesized with TiAl-target arc sources to emit ion plasma to activate acetylene reactive gases. Scanning electron microscopy (SEM), Auger electron spectroscopy (AES), micro-Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) techniques were employed to analysis the microstructure properties of TiAl-doped DLC coatings. Vicker's and tribometer tester were used to measure the mechanical properties of TiAl-doped DLC coatings. The results show that the TiAl-doped DLC coatings retained lower friction coefficient at approximately 0.15 during the steady state sliding. The lubricity and wear resistance of TiAl-doped DLC coatings is then demonstrated to potentially be applied to the cutting tools with no lubricants.