Applied Surface Science, Vol.357, 2160-2168, 2015
Enhancing the oxidation resistance of copper by using sandblasted copper surfaces
We show that sandblasting can be employed to effectively enhance the oxidation resistance of copper by suppressing the interfacial delamination between copper and its oxide by modifying the surface roughness of Cu. Increasing sandblasting treatment time from 0 to 120 s increases the surface roughness of Cu from 0.12 +/- 0.003 pin to 2.89 +/- 0.176 mu m, which results in improved oxidation resistance of the Cu surfaces and enhances the oxide/substrate interfacial fracture energy from 0.035 J/m(2) to 3.1 J/m(2) determined using nanoindentation. The sandblasting treatment has no appreciable effect on the Young's moduli of the Cu oxide film, which remain nearly constant at around 36 GPa. The improved oxidation resistance is ascribed to the enhanced interfacial adhesion of the sandblasted copper owing to the concave shape of craters generated by sandblasting, which results in a net downward force from the compressive stresses in the oxide film that forces the film to adhere to the Cu substrate. (C) 2015 Elsevier B.V. All rights reserved.