|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Advanced Real Time Imaging
||Assessing the Evolution of Pit Growth Kinetics during Atmospheric Corrosion Using In-situ X-ray Tomography
||Philip Noell, Eric Schindelholz, Michael Melia, Ian Campbell
|On-Site Speaker (Planned)
Within the field of corrosion, the relationship between environment and the kinetics of pit growth during atmospheric corrosion attack remain poorly understood. Using in-situ X-ray microtomography, we directly observed pit growth in Al materials and the relationship between growth kinetics and the evolving surface environment over months of exposure. While previous studies suggested that growth kinetics are roughly linear, the present study indicates that growth rates can vary significantly in some cases. This depends on the evolution of the droplet, e.g. droplet spreading, as well as the morphology of the pit. In-situ measurements also revealed that in the hours immediately before repassivation, growth stalled then accelerated. A corrosion-driven drying mechanism is hypothesized to change droplet chemistry and produce this behavior. SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525.