Investigation of the Antibacterial Behavior of Thin Film Metallic Glass Alloy Zr30Cu20Al10Ag10Cr10Si10B10 Applied on 316 Stainless Steel Substrate

Stainless steels 316 and 304 are among the alloys commonly used to make medical equipment, including surgical instruments. These steels, however, do not exhibit properties that control bacterial growth or destroy bacteria upon contact, leading to significant contamination. This problem can be largely mitigated by applying coatings with high antibacterial properties. One such coating that has attracted considerable attention from researchers, in recent years, is Zr-based metallic glass coatings. In this study, after studying the effects of different elements on the antibacterial behavior of coatings, an alloy with the chemical composition of Zr30Cu20Al10Ag10Cr10Si10B10 was designed and produced. A thin layer of this amorphous alloy was then applied to a 316 stainless steel substrate, and its behavior against two common hospital bacteria was studied. After weighing and mixing the selected elements in the required stoichiometric ratios and homogenizing them using a mechanical ball mill, a target with the desired chemical composition was produced using Spark Plasma Sintering (SPS). Structural investigations revealed a uniform distribution of the elements in the produced target. Using this target, thin layers of the alloy with different thicknesses were deposited on the 316 stainless steel substrate. Preliminary investigations showed that the coatings, in addition to forming a good bond with the substrate, possess a glassy and amorphous structure. The antibacterial behavior of the coatings against Escherichia Coli and Staphylococcus Aureus was then investigated. The results showed that the coatings, due to the presence of copper and silver, exhibit high antibacterial properties against these bacteria. Furthermore, the application of the coating, which reduces the roughness of the polished 316 substrate by 50%, can significantly affect the adhesion of human and animal blood platelets, as well as human and animal cancer cells, to surgical instruments made from 316 stainless steel.