The additive manufacturing (AM) technique can produce Ti-6Al-4V ELI (extra low interstitial) alloy for personalized biomedical devices. However, the Ti-6Al-4V ELI alloy presents poor tribological behavior. Regarding this, coatings are a feasible approach to improve the wear resistance of this alloy. In the literature, the tribological behavior of TiO₂ coatings incorporated with Ca and P formed by one-step plasma electrolytic oxidation (PEO) on Ti-6Al-4V ELI alloy processed by AM has not been investigated. Thus, in the present work, it was studied the influence of Ti-6Al-4V ELI alloy processed by AM on the wear resistance and morphologic of the coating obtained by PEO (plasma electrolytic oxidation). In this way, three different voltages (200, 250, and 300 V) were employed for the PEO process and the voltage effect on the properties of the coatings. The coatings were characterized by contact profilometry, scanning electron microscopy, energy-dispersive spectroscopy, the sessile drop method, grazing-incidence X-ray diffraction, and wear tests, on a ball-on-plate tribometer. The increase in applied voltage promoted an increase in roughness, pore area, and a decrease in the pore population of the coatings. In addition, the coatings, mainly composed of anatase and rutile, showed good adhesion to the metallic substrate, and the presence of bioactive elements Ca and P were detected. The thickness of the coatings obtained by PEO increases drastically for voltages higher than 250 V (from 4.50 ± 0.33 to 23.83 ± 1.5 µm). However, coatings obtained with lower voltages presented thin and dense layers, which promoted a superior wear resistance (increase in wear rate from 1.99 × 10⁻⁶ to 2.60 × 10⁻⁵ mm³/s). Finally, compared to the uncoated substrate, the PEO coatings increased the wear resistance of the titanium alloy obtained by AM, also showing a superior wear resistance compared to the commercial Ti-6Al-4V alloy previously evaluated, being such a positive and promising behavior for application in the area of metallic implants.

A Cu-TiO₂ nanomaterial with unique antibacterial and photocatalytic properties is introduced in this study. Cu-TiO₂ nanocomposites were obtained using an adapted direct current magnetron sputtering apparatus, where TiO₂ anatase nanoparticles (NPs) were used as the substrates and copper as the sputtering target. The obtained powder was characterized by physical and chemical methods. Copper was deposited on TiO₂ NPs for 30 and 60 min, resulting in two samples with different copper contents of 3 and 5 wt %, respectively. The photocatalysis test evaluated the degradation of rhodamine B (RhB) dye under a specific wavelength (405 nm LED) and a complete degeneration occurred in 120 min, ∼ 33% faster when compared to pristine TiO₂. The antibacterial assays were performed for Escherichia coli and Staphylococcus aureus in dark and visible-light conditions, using a 405 nm LED and a wide-spectrum white LED, reaching an inactivation of 99.9999% for both bacteria. The magnetron sputtering is an ecofriendly way to form heterojunctions with photocatalytic and bactericidal properties in the absence of wet chemical methods or residues. This work may open new pathways for enhancing the fungicidal and virucidal activities of nanocomposites under the action of visible light.

The radiological protection has the purpose of safeguarding the physical well-being of the user, preventing exposure to detrimental levels of ionizing radiation. This study introduces a novel, cost-effective category of lead-free elastomeric material designed for radiation shielding. The filler compounds utilized are notably lighter than conventional lead-based materials, enhancing user ergonomics during application. They comprise of a blend of barium sulfate combined or not with magnesium oxide with addition-cure liquid silicone rubber. To ensure the effectiveness of the radiation shielding, X-ray transmission measurements were performed for the different thicknesses of the materials and the results compared with Monte Carlo simulations. Additionally, the physical properties of the new materials, such as density, homogeneity, tensile strength, viscosity, and wettability, were also evaluated. The findings indicate that both materials fulfill the requirement for application in radiation protection garments.