Decoupling the role of microstructure and geometric discontinuity introduced by weld reinforcement height on corrosion behavior of SA106B/316L SS welded joint in the flowing 0.5 M NaCl solution

The flow-influenced corrosion (FIC) behavior of SA106B/316L stainless steel (SS) welded joints with SS located upstream and downstream is investigated experimentally and numerically. The damage components of microstructure heterogeneity and geometric discontinuity are quantified. The FIC of the welded joint is affected by the combination of galvanic corrosion, mass transfer, and charge transfer. The electrochemical measurements indicate that the corrosion is aggravated by a flow disturbance component of 18.70%~26.96%. The corrosion of SA106B carbon steel is more severe than 52M and 316L SS due to galvanic effect, which is further promoted by flow disturbance. The FIC mechanism is also discussed.