Zrcuag Thin-Film Metallic Glasses: Toward Biostatic Durable Advanced Surfaces

A combinatorial approach has served as a high-throughput strategy to identify compositional windows with optimized desired properties. Here, ZrCuAg thin-film metallic glasses were deposited by DC magnetron sputtering. For the purpose of using these coatings as biomedical surfaces, their durability in terms of mechanical and physicochemical properties as well as antibacterial properties were characterized. The effect of the chemical composition of thin films was studied. In particular, two key parameters were highlighted: the atomic ratio of Zr/Cu (with three values of 65/35, 50/50, and 35/65) and the silver content (from 1 to 16 at. %). All thin films are XRD amorphous and exhibit a typical veinlike pattern, which is characteristic of metallic glasses. They also show a dense and smooth surface and a hydrophobic behavior. Mechanical properties are found to be deeply influenced by the Zr/Cu ratio and the atomic structure. Although a low Zr/Cu ratio and/or a high silver content is detrimental to corrosion behavior, it favors the bactericidal effect of thin films. For all Zr/Cu ratios, ZrCuAg thin-film metallic glasses with silver contents higher than 12 at % are fully bactericidal. For lower silver contents, the bactericidal effect progressively decreases, which paves the way for a biostatic behavior of these surfaces.