Direct measurement of corrosion inside iron crevices

Using visible crevices formed between 8 x 4 x 0.2 cm iron plates and 8 x 2.5 x 0.2 cm glass sheets, with widths of 100, 200 and 300 gm achieved by adhesive tapes of the appropriate thickness, drying kinetics were determined as a function of crevice width and environmental relative humidity. Determinations were also made of the corrosion rate inside the crevice by gravimetry, the aspect of the corrosion products by visual observation, and the morphology of attack by optical microscopy. The corrosion kinetics results indicate that dissolved oxygen in the electrolyte inside the crevice is renewed thousands of times over the course of several days.