The Effect of Deposition Conditions on Atmospheric Pitting Corrosion Location Under Evans Droplets on Type 304L Stainless Steel

摘要

Pit location during atmospheric corrosion of Type 304L stainless steel under MgCl2 droplets depends on initial droplet concentration. Pits formed predominantly in the center of the droplet for concentrations = 4 M, closer to the perimeter for 1.5 M to 3 M, and were randomly distributed for concentrations 1 M. Pits initiated only after the droplets had evaporated to a critical concentration 3 M, where droplets deposited with lower initial concentrations were thinner. The results can be explained in terms of "differential aeration" and IR drop effects, showing that corrosion in "splash zones" may differ from that under aerosol salt deposit layers that deliquesce forming initially saturated solutions.