Effects of hydrogen on the crevice corrosion behaviors of duplex stainless steel 2205
Pei He, Donghua Suo, Wenbo Wu, Liqiang Yin, Dai Wei, Binggang Shang, Yuanyuan Liu, Yangting Sun, Yiming Jiang, Jin Li
Abstract
Crevice corrosion behaviors of duplex stainless steel 2205 after hydrogen charging are investigated. The absorbed hydrogen is introduced into the specimens through cathodic galvanostatic method. It has been found the absorbed hydrogen decreases the critical crevice corrosion conditions (breakdown potential, temperature, and chloride ions content), the stable propagation potential, and the repassivation potential. The results reveal that hydrogen can promote the initiation and propagation stages and inhibit the repassivation process of crevice corrosion. Microstructure observation and element distribution analysis find that, owing to the promotion of hydrogen on the precipitation of insoluble molybdenum oxides and molybdate at the bottom of corrosion positions, crevice corrosion of the hydrogen charged specimens exhibits wider but shallower morphologies compared with the uncharged specimens.