Anticorrosion performance of a Zr-based architectured substrate/coating system

After Zr+ HiPIMS etching, four Zr-based substrate/coating systems were synthesized on 304L stainless steel by hybrid pulsed DCMS/HiPIMS. SEM-BSE images showed an open columnar structure. The coating effect on corrosion was investigated in nitric acid and compared to tantalum considered as reference material in terms of corrosion behavior. Electrochemical measurements in nitric acid at boiling temperature showed that the corrosion resistance of Zr-based coatings was similar to tantalum (coating and bulk) and better than uncoated 304L steel after 2 d of immersion. Longer immersion tests confirmed these results. No intergranular corrosion was observed on coated samples compared to uncoated 304L.