|
Abstract
|
In this study, diamond-like carbon (DLC) and titanium carbonitride (TiCN) coatings were deposited as gradient interlayers on a Ti6Al4V (Ti64) substrate using the PACVD method to improve its surface properties. To investigate the mechanical and tribological behaviors, nanoindentation, hardness testing, adhesion, and pin-on-disk (POD) tests were conducted. Furthermore, FESEM, OM, XRD, and Raman spectroscopy were used to analyze the surface of the samples. Results showed that the TiCN interlayer improved adhesion and increased coating thickness to 1009.40 nm after 3 h of deposition. The coating’s effect on the surface properties of Ti64 was also evaluated. Coated Ti64 exhibited a higher hardness (33.5 GPa) and lower reduced elastic modulus (Er) (62 ± 5 GPa) compared to the uncoated substrate’s 4.25 and 148.5 GPa, respectively. Ti64-TiCN/DLC exhibited oscillations in the coefficient of friction (μ), whereas the uncoated substrate showed a relatively constant μ of about 0.23. The investigation showed that the average specific wear rate (K) due to coating decreased from 7.8 × 10−13 to 3.7 × 10−14 m3 Nm−1. OM images showed that the wear mechanism of Ti64-TiCN/DLC was adhesive, while that of the uncoated Ti64 was abrasive.
|