By js55
Date 03-21-2014 12:31
Edited 03-21-2014 12:34
Good stuff Henry though I would add that duplex has been around quite awhile. If memory serves, there was a german patent developed as early as 1929. Also if memory serves, they just didn't know quite what to do with it.
The SS filler ER312 is essentially a duplex alloy, though we don't call it that, we call it a high ferrite SS useful for applications where cracking is problematic. And its been around a long time. By todays measuring system of FN, measuring ferrite has proven tricky and controversial, it can demonstrate an FN of as much as 30. 30FN by anybody's assessment is duplex.