Corrosion of a Zn-Al-Cu alloy coated with TiN/Ti films

摘要

TiN and Ti coatings were deposited by d.c. magnetron sputtering on a Zn-Al-Cu alloy. The coatings were deposited at a relative low temperature of 115-130℃. X-ray diffraction showed that the films were crystalline. A pure titanium interlayer wasused to improve the adhesion and corrosion resistance of the titanium nitride films. The corrosion behavior of samples in NaCl solutions was studied using polarization curves. Scanning electron microscopy was used to study the corroded samples. It wasfound that corrosion resistance of coated alloy was higher than the substrate resistance. Furthermore the corrosion resistance is mainly controlled by the presence of defects In the TiN and Ti films.