Efficacy of Electropolishing on the Surface of Ti-6Al-4V ELI Alloy to Minimize Bacterial Adhesion on Implants

Titanium and its alloys are the most commonly used materials for biomedical applications such as implants. The Ti-6Al-4V ELI (Extra Low Interstitial) alloy is particularly desired for its excellent mechanical performance and remarkable biocompatibility. However, infection is a limiting factor after implantation, making it necessary to adopt surface treatment to minimize this process. Bacterial adhesion to the substrate is strongly influenced by surface roughness and wettability. Therefore, the present study aims to evaluate these parameters after dry electropolishing of the Ti-6Al-4V ELI alloy. The Ti-6Al-4V ELI samples were sectioned with Ø = 14 mm and 3 mm thick, followed by sanding with silicon carbide #600, #1200 and #1600. Subsequently, they were sent for dry electropolishing for 30 min with a voltage potential of 13 to 18 V and characterized. Data were processed statistically using ANOVA. The Ra roughness values were statistically significant: 143±24 nm for 17 V compared to 193±18 nm for the control. The wettability test confirmed that all surfaces obtained are considered hydrophilic, favorable for lower bacterial adhesion, with 16 V being the best condition. Contact angle was found to be 77±6° for 16 V and 59±4° for the control. Dry electropolishing is essential for surface enhancement and biomedical applications.