Properties Of Antibacterial Cu/TiN Nano-Multilayer Coatings Fabricated By Magnetron Sputtering

The conception of healthy life has become a tidal current with the development of economy. Antibacterial materials have been paid more and more attention in this green life. Stainless steel with antibacterial ability has gained much interest since it has been widely used in modern life.In this paper, we fabricated Cu/TiN nano-multilayer on stainless steel substrate using hybrid DC and RF magnetron sputtering technology. And Cu ion had also been implanted into stainless steel, titanium alloy and aluminum by metal vapor vacuum arc ion source (MEVVA). Optical microscope (OM) and scanning electronic microscope (SEM) were used to observe the surface topography and structures. X-ray photoelectron spectroscope (XPS), X-ray energy spectrum (EDS) and X-ray diffraction (XRD) were used to analysis the distribution and the valence of the elements as well as the phase structures., potentiodynamical polarization test was performed to evaluate the corrosion-resistance of the layers and topography of the surface was observed after the soak test in 0.87%NaCl bacteria solution. Wear resistance, micro-hardness and nano-indentation hardness were also tested. Antibacterial abiliy to Escherichia coli and staphylococcus aureus of the layer was evaluated using plate-counting method.The nano-multilayer structure of the layers can be observed clearly from the surface and cross-section morphology. When either one of the two types of layers (i.e. Cu and TiN) is too thick, great stress is induced that would lead to cracks or complete peeling of the layer. Therefore, nano-multilayer should be produced in proper modulation period to get excellent surface structure and properties. The hardness of the treated samples has been improved evidently, and the nano-indentation hardness test also shows that the hardness of the film increases with increasing the ratio of the TiN in the multilayer. In the ball-on-disk tests, multilayer coatings display good wear resistance due to the good lubrication effect of the brass layer and the high hardness of the TiN layer. With proper modulation period, multilayer possesses low friction coefficient and good wear resistance. The longest breakthrough time of the coatings exceeds 8000 seconds. The aluminum samples display much better wear resistance than the base sample...