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Regarding the pitting on 316 SS

2006

I have noticed a pitting on my flexible metal hoses 316 stainless steel in an environment near to the sea. what is the main reason of this formation? please provide any reference.
thanks

Hani [last name deleted for privacy by Editor]
- Saudi Arabia

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2006

316L is not resistant to seawater attack. In fact, we use it as a control in our tests knowing that it will experience corrosion. If you want to avoid attack in marine environments, 316 is not the way to go. For stainless steels, you need to have a 6% Mo alloy or better (25-6MO, 27-7MO) or Ni-Cr-Mo alloys to resist corrosion. NACE conferences will have many references to both 316 failures and the nickel base alloy solutions in seawater. (I know you said it was not IN seawater,but when it is in the vicinity to seawater, salt spray from the ocean will certainly affect it.)

Nate Eisnger
special metals - Huntington, West Virginia