Morphological, mechanical and antibacterial properties of Ti–Cu–N thin films deposited by sputtering DC

The problems associated with Stainless Steel 316 L (SS 316 L) orthopedic implants, when implanted in the human body, are infection, local inflammation, and the possibility of bacterial growth. In this study, SS 316 L was coated with copper-doped Titanium Nitride (Ti–Cu–N) using the DC Sputtering technique. This Ti–Cu–N film improved the antibacterial performance and mechanical properties of SS 316 L. The Ti–Cu–N films were deposited using reactive DC sputtering with an 80%:20% argon to nitrogen ratio. The source voltage and current were kept constant at 10 kV and 10 mA, respectively. X-Ray Diffraction (XRD) showed that the phases formed were TiN and Cu with FCC crystal structure. Results show that the surfaces of samples containing 44.34 wt% and 54.97 wt% Cu had antibacterial effectiveness against Staphylococcus aureus (S. Aureus). The highest hardness value of a Ti–Cu–N layer was 212.032 Vickers Hardness Number (VHN), which was an improvement of 36.63% on the raw material (155.18 VHN). Surface morphology analysis using SEM-EDS was performed on the samples before and after the antibacterial test to investigate the antibacterial mechanism of the surfaces of SS 316 L containing Ti–Cu–N against S. Aureus.