What are some industry standards for the testing of proper passivation on 316 stainless castings? I am looking for ASTM, AISI type standards to reference.Jeff Griesenauer
- Bryan, Ohio, USA
ASTM A967 [affil. link to spec at Techstreet] , "Chemical Passivation Treatments for Stainless Steel Parts", is probably what you want. There is also AMS2700 [affil. link to spec at Techstreet], which will eventually (when AMD Committee B gets our act together) replace AMS-QQ-P-35C [link is to free spec at Defense Logistics Agency, dla.mil], the word-for-word replacement of the canceled Federal Specification QQ-P-35.
There are some tests listed in ASTM A 967, in sections 14 through 18. They list water immersion, high humidity, salt spray, copper sulfate, and potassium ferricyanide-nitric acid testing as appropriate. Just remember that a casting has a surface scale that must be removed before proper passivation can occur. If you don't get it removed, then don't be surprised if you fail any of the tests.
metallurgist - E. Aurora, New York