Posted by TVP on July 18, 2008 at 12:25:55:
In Reply to: Etching of S31254 posted by JJ on July 14, 2008 at 12:02:10:
It is possible that the etchants are revealing carbide particles or sigma phase, which is a brittle intermetallic with the ~ composition of FeCr. Discrete "spots" sounds more like carbide particles than sigma phase, which usually has a duplex appearance with the austenite. Electrolytic etching with NaOH colors sigma orange, so you could try that if this is a concern.