Enhanced Pitting Corrosion Resistance of CoCrFeMnNi High Entropy Alloy in the Presence of Desulfovibrio Vulgaris Via Nitrogen Doping

Corrosion-resistant high nitrogen high entropy alloys (HEAs) were manufactured by pressurized metal-lurgy. This work revealed the inhibitory effect of nitrogen on pitting corrosion of HEAs caused by sul-fate reducing bacterium Desulfovibrio vulgaris. Results indicated that HEA-0 N was susceptible to pitting corrosion and sulfidation under attack of D. vulgaris, whereas the addition of nitrogen significantly de-creased the pitting sensitivity. Pitting potentials of HEA-0.52 N and HEA-1.23 N increased by 133% and 171%, respectively compared to HEA-0 N in the presence of SRB. X-ray photoelectron spectroscopy results unveiled that nitrogen enriched in passive film and strengthened it by increasing fraction of Cr2O3 and Fe3 + ox . Surface of the nitrogen-alloyed HEAs exhibited less defective passive films as revealed by Mott -Schottky results. Nitrogen doping provides a novel insight into the design of microbial corrosion resistant HEA.(c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.