Corrosion resistance of SiO2 thin film coated biomedical Ti-13Nb-13Zr titanum alloy by E-Beam

Biomedical Ti-13Nb-13Zr titanium alloy (ASTM F1713) subjected to hydrostatic extrusion (HE) process to obtain enhanced mechanical properties and change its specific surface energy by increasing amount of grain boundaries via grain refinement¹. Thus, it is expected to have difference in coating and corrosion properties when compared to their as-received conditions. Disc shaped specimens has been prepared from as-received and HE processed material as substrates for three different surface roughness. Thin film SiO₂ has been coated onto substrates by physical vapour deposition (PVD) using E-Beam with a voltage of 6 kV and 50 mA of emission current under 2.10^-6 torr pressure. In vitro corrosion resistance test has been performed in Hank´s solution at 37°C (body condition) to compare the results according to the initial surface conditions of the substrates. All surfaces conditions before and after corrosion test has been investigated by scanning elctron microscope.