Quote:
Originally Posted by Gatto Nero
I Googled. Here is what I found.
"Crevice Corrosion
The corrosion resistance of a stainless steel is dependent on the presence of a protective oxide layer on its surface, but it is possible under certain conditions for this oxide layer to break down, for example in reducing acids, or in some types of combustion where the atmosphere is reducing. Areas where the oxide layer can break down can also sometimes be the result of the way components are designed, for example under gaskets, in sharp re-entrant corners or associated with incomplete weld penetration or overlapping surfaces. These can all form crevices which can promote corrosion. To function as a corrosion site, a crevice has to be of sufficient width to permit entry of the corrodent, but sufficiently narrow to ensure that the corrodent remains stagnant. Accordingly crevice corrosion usually occurs in gaps a few micrometres wide, and is not found in grooves or slots in which circulation of the corrodent is possible. This problem can often be overcome by paying attention to the design of the component, in particular to avoiding formation of crevices or at least keeping them as open as possible. Crevice corrosion is a very similar mechanism to pitting corrosion; alloys resistant to one are generally resistant to both. Crevice corrosion can be viewed as a more severe form of pitting corrosion as it will occur at significantly lower temperatures than does pitting."
Not sure I follow what the problem is. I figure my other choice was a galvanized eye and I don't see how that would be any better.
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"To function as a corrosion site, a crevice has to be of sufficient width to permit entry of the corrodent, but sufficiently narrow to ensure that the corrodent remains stagnant."
In this situation, the water is the corrodent and the concrete allows water in but not to flow, so it remains stagnant. This makes the SS corrode very quickly and invisibly (it's invisible because the corrosion can only occur within the tight confines of the crevice, if it's plainly visible, there will be no corrosion).
Here's a nice example of a stainless bolt compared to bronze bolt:
