G48 test failure consequence
G48 test failure consequence
(OP)
Hi all,
If a J93404 Superduplex casting material fails the G48 method A corrosion test, does this mean it will FOR SURE corrode in operation in a seawater line?
If a J93404 Superduplex casting material fails the G48 method A corrosion test, does this mean it will FOR SURE corrode in operation in a seawater line?





RE: G48 test failure consequence
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: G48 test failure consequence
Second, does this material pass the A923? (similar test solution but entirely different goal)
What does the microstructure look like?
I may have failed because of poor test method. Lets work through this.
If the test was done correctly it does mean that the castings will pit in seawater a lower temperature than you would normally expect for the chemistry. If this is too low then you have failures.
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Plymouth Tube
RE: G48 test failure consequence
A923 was not requested and not done.
The microstructure showed some intermtellic phases and imperfections, the ferrit content was in the high range of 65%.
We did a so called "ferroxile" test and the material passed.
RE: G48 test failure consequence
NEVER buy a duplex without requiring A923. Reject it. It was not annealed correctly. Use the G48 as the basis, or use poor workmanship, wrong microstructure.
Also I suggest that you switch to G48 method C, even if you have to go to a lower test temp like 45C. The test is more repeatable.
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Plymouth Tube
RE: G48 test failure consequence
GUIDANCE DOCUMENT FOR THE EVALUATION OF CAST SUPER DUPLEX STAINLESS STEEL
http://ww
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Corrosion Prevention & Corrosion Control