Structure and tribology of biocompatible Ti–C:H coatings

Ti–C:H coatings with different carbon content for biomedical applications were deposited by PECVD. Ti was varied by magnetron sputtering a Ti-target with different power in a dc discharge regime having Ar in the atmosphere. Ti–C:H coating was tribologically tested reflecting its expected use as an interlayer for improving the adhesion of functional a-C:H coatings. The tribological properties were studied using a pin-on-disc CSM Tribometer in order to ensure stable tribological properties of the whole Ti–C:H/DLC system for any case of top layer failure. The sliding tests were carried out at room temperature in room environment with relative air humidity 40 ± 5%, in 0.9% NaCl water solution (physiological solution, PS) and in 10% fetal bovine serum (FBS) dissolved in Ringer's saline solution using 440C steel balls with a diameter of 8 mm. The variation of the C2H2 flow led to carbon contents in the range [18–91 at.%]. The Ti-rich coatings exhibited poor wear resistance, while the best tribological properties were achieved for TiC/a-C:H coatings deposited with the highest C2H2 flows. When tested in biological solutions, the friction and wear resistance were analyzed with respect to their corrosion propertie

Ultrathin TiO₂ Coatings via Atomic Layer Deposition Strongly Improve Cellular Interactions on Planar and Nanotubular Biomedical Ti Substrates

This work aims to investigate the chemical and/or structural modification of Ti and Ti-6Al-4V (TiAlV) alloy surfaces to possess even more favorable properties toward cell growth. These modifications were achieved by (i) growing TiO2 nanotube layers on these substrates by anodization, (ii) surface coating by ultrathin TiO2 atomic layer deposition (ALD), or (iii) by the combination of both. In particular, an ultrathin TiO2 coating, achieved by 1 cycle of TiO2 ALD, was intended to shade the impurities of F- and V-based species in tested materials while preserving the original structure and morphology. The cell growth on TiO2-coated and uncoated TiO2 nanotube layers, Ti foils, and TiAlV alloy foils were compared after incubation for up to 72 h. For evaluation of the biocompatibility of tested materials, cell lines of different tissue origin, including predominantly MG-63 osteoblastic cells, were used. For all tested nanomaterials, adding an ultrathin TiO2 coating improved the growth of MG-63 cells and other cell lines compared with the non-TiO2-coated counterparts. Here, the presented approach of ultrathin TiO2 coating could be used potentially for improving implants, especially in terms of shading problematic F- and V-based species in TiO2 nanotube layers