Corrosion of metal iron in contact with anoxic clay at 90 °C: Characterization of the corrosion products after two years of interaction

The average thickness of oxidized iron, as measured by the average of distances from the original to the final metal surface, was 13 ± 1 and 15 ± 1 μm for the massive rod and the micro-overpack, respectively. The corresponding Fe amount is about twice the amount of Fe present in the corrosion products. Thus a significant Fe fraction migrated in the nearby clay, likely as Fe(II), and could act as a significant buffer of the electrochemical potential.