Work packages
The workload is divided into four work packages.
Figure: Schematics of the work sequence with the example of application to archaeology and conservation.
The main goal is to elucidate the corrosion mechanisms and kinetics of buried iron scales in model porous media subjected to different environmental transitions. Because of the chemical complexity and structural variability of soils we propose an original systematic approach, allowing the separation of the effect of transport phenomena from the chemical and electrochemical reactions of the buried metal. The transport phenomena, that are highly variable depending on the soil nature, will be mimicked by using inert membranes and bentonite, both of well-controlled porosities and ion exchange properties, combined with sudden changes in the electrolyte composition (environmental transients). With respect to inert membranes, the use of bentonite allows to introduce ion-exchange and redox reactions occurring inside of the porous media. This part will be carried out in collaboration with Nagra that has an extensive experience in the field of corrosion in bentonite.
Figure: Applicability of X-ray/neutron imaging to study corrosion in concrete. a) Test procedure, b) Bimodal segmentation results: air voids (blue), steel bar (grey), corrosion products (red) (the concrete is “digitally stripped off” to visualize the features inside the concrete).
Figure: Systematic experiments to investigate the transient changes for iron artifacts in soil.