Sol–gel preparation and properties of Ag–TiO₂ films on surface roughened Ti–6Al–4V alloy

Abstract

Ag–TiO 2 films (Ag/Ti = 3·3, 9·1 at-) were sol–gel coated on Ti–6Al–4V alloy that had been surface roughened by the NaOH–HCl treatment for antibacterial applications. Scanning electron microscopy observation showed that pore size of the surface layer of NaOH–HCl treated Ti–6Al–4V alloy increased with the NaOH concentration. Ag–TiO 2 films on the surface roughened substrate were adherent and crack-free. X-ray photoelectron spectroscopy and Auger electron spectroscopy analyses indicated that Ag existed in metallic state, and the films completely covered the roughened substrate. X-ray diffraction peaks of the substrate and anatase TiO 2 were detected. The Ag–TiO 2 films on the roughened substrate exhibited good adhesion quality and high cohesion strength in the indentation test. The potentiodynamic polarisation test showed that the TiO 2 and Ag–TiO 2 films improved corrosion resistance of the substrate.