Effect of C2H2 flow rate and a Ti/TiN/TiCN interlayer on the structure, mechanical and tribological properties of a-C:H films deposited using a hybrid PVD/PECVD process with an anode-layer ion source. (March 2023) - Su, Zhijun
Abstract: Diamond-like carbon (DLC) films were deposited onto 316L stainless steel using the hybrid physical vapor deposition (PVD)/plasma-enhanced chemical vapor deposition (PECVD) process with an auxiliary anode-layer ion source at C2 H2 flow rates of 40–100 sccm to enhance mechanical and tribological properties of a-C:H films. The films were characterized using transmission electron microscope (TEM), field emission scanning electron microscopy (FESEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), nanoindentation and ball-on-disk rubbing tribometry. The hardness, tribological properties and interfacial bonding were significantly improved in the presence of the Ti/TiN/TiCN interlayer deposited by high-power impulse magnetron sputtering (HiPIMS). Results showed that a-C:H films were uniform and dense, the sp 3 C content increased with an increase in the C2 H2 flow rate from 40 to 80 sccm, and decreased when it was further increased to 100 sccm. The a-C:H film with the interlayer prepared at 80 sccm C2 H2 exhibited the highest hardness (27.2 ± 0.5 GPa), H/E (0.137), and H 3 /E 2 (0.510). Moreover, friction-wear tests demonstrated that the incorporation of the Ti/TiN/TiCN layer increased the wear resistance of the a-C:H film, achieving the lowest coefficient of friction (CoF, 0.148), wear rate (1.08 × 10 −9 mm 3 N −1 mm −1 ) and width of the wear track (177 μm) at 80 sccm C2 H2 . Highlights: DLC films were deposited on 316L stainless steel via a hybrid PVD/PECVD process. A Ti/TiN/TiCN interlayer was formed using the HiPIMS process. The a-C:H film with an interlayer exhibited high hardness and wear resistance. High-quality films with improved mechanical and tribological properties were formed.