|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Environmentally Assisted Cracking: Theory and Practice
||NOW ON-DEMAND ONLY – Role of Accumulated Plastic Strain on Grain Boundary Corrosion of Steel
||Amir Abdelmawla, Kaustubh Kulkarni, Ashraf Bastawros
|On-Site Speaker (Planned)
Steel structures may experience localized plastic strains, arising from wide range of service anomalies. Regions of accumulated plastic strain are more prone to accelerated stress corrosion cracking. Here, we systematically analyzed the intergranular corrosion (IGC) at potentials of active dissolution in moderately alkaline carbonate-bicarbonate solutions and under pre-accumulated plastic strain ranging from 0-2.5%. We report the strain-dependent morphological evolution during the initial stage of IGC of X70 steel in sodium bicarbonate solution, in the potential range of high SCC susceptibility. At potentials in the range of SCC susceptibility, IGC creates triangular wedges of porous corrosion products centered at grain boundary triple junctions. The wedges shapes and the total integrated charge from the polarization curves where greatly affected and correlated with the level of the accumulated plastic strains. These findings provide a plausible link of a coupled chemical-mechanical mechanisms responsible for the accelerated SCC in regions of plastically deformed structures.