Papers by Author: Qiu Rong Chen

Abstract: TiO2 films were deposited on AZ31 magnesium alloy substrates by r.f. magnetron sputtering. The corrosion behaviors in simulated body fluid (SBF) of the film samples were investigated and compared to the bare AZ31 magnesium alloy. After 3 days’ corrosion in SBF, only part of the TiO2 layer suffered from corrosion and the substrate was prevented from corrosion. In contrast, the bare magnesium alloy suffered from severe corrosion. After 10 days’ corrosion, the TiO2 layer was penetrated and the substrates still did not suffer from corrosion. After 15 days’ corrosion, besides TiO2 layer, the substrate suffered from corrosion to some degree. The depth of the corrosion layer is about 6 m, which is far lower than that of bare magnesium alloy, 40 m. The results show that TiO2 films effectively improve the corrosion properties of magnesium alloys.

Abstract: TiN films were deposited on the AZ 31 magnesium alloy substrates by d.c. magnetron sputtering technique. The surface properties of the films were investigated. The scanning electronic microscope observations reveal the dense structure characteristics of as-deposited TiN films. Under 200°C heat treatment for 30 minutes or 4 times’ heat cycles at 85°C for one hour, no structural defects such as cracks are observed on the surface of the films. Adhesion experiment further demonstrates the stability of the film and the strong combination between the film and the substrate. Nano-indentation experiment shows that the average micro-hardness of TiN film reaches 23.85 Gpa. Finally, the corrosion experiments in simulated body fluid initially reveal the degradation property of TiN film.