Argon versus nitrogen ion beam assisted deposition of amorphous carbon and carbon-nitrogen films on aluminum for protection against aqueous corrosion

摘要

Ion beam assisted deposition has been used to deposit amorphous C and CN_x films on aluminum at room temperature by electron beam evaporation of graphite under concurrent ion beam irradiation with two different ions, argon and nitrogen. The corrosion properties of the films in chloride-containing water were examined by electrochemical polarization techniques. The results show that argon ion bombardment is more effective than nitrogen ion bombardment. The aluminum dissolution currents are higher when nitrogen ions are used in comparison to argon ions. Apparently, interface mixing which leads to a heterogeneous ternary Al-C-N phase is detrimental to the corrosion protection effect of the thin film.