Nano-sized zeolite particles as inhibitor carrier in plasma electrolytic oxide layers on AZ31

Plasma electrolytic layers on AZ31 provide an efficient corrosion protection. However, the process-related pores and holes are weak points in view of risk of corrosion. The incorporation of a small amt. of nano-sized inhibitor-loaded zeolite particles leads to a significant improvement of the corrosion resistance. The study shows that the inhibitor-loaded particles can be incorporated directly during plasmaelectrolytic oxidn. in a one-step-process. The risk of pitting corrosion decreases in comparison with inhibitor free anodized layers and the cerium inhibitor was found to deposit directly inside pits.