Passivated Per QQ-P-35C,type 11
Passivated Per QQ-P-35C,type 11
(OP)
Does anyone know the difference between Passivate Per QQ-P-35C,type 11 and Passivate Per QQ-P-35,type 11. I don't have access to the specs but I'm sure the differences must be small. Thank you.





RE: Passivated Per QQ-P-35C,type 11
QQ-P-35C does not have Type 11.I, or Type 11, but does have Type II but no II.I or II.1.
QQ-P-35C was superseded by AMS-QQ-P-35A, but alas, AMS-QQ-P-35A has been cancelled, and superseded by AMS2700E, that also does not have a Type 11 or Type II, but does have Type 2.
In AMS-QQ-P-35A, if you wanted to use Type II, you now need to call-out AMS2700E Type 2.
In AMS2700 you can use Method 1 which is passivation in Nitric Acid, or Method 2 which is passivation in Citric Acid.
RE: Passivated Per QQ-P-35C,type 11
RE: Passivated Per QQ-P-35C,type 11
QQ-P-35 original [rev 'new'] Specifies Types I, II and III [low temp, medium temp and high acid bath temperatures, respectively].
QQ-P-35 rev B Type I - Low temperature, Type II - Medium temperature, Type III - High temperature, IV - For steels containing large amounts (0.15 percent) of sulfur or selenium,
Type V Anodic - For high carbon martensitic (IE 44O) steels and Type VI - an Low temperature (solution).
QQ-P-35 rev C revised the 'gene-pool' one more time: eliminated types I, III, IV, V and added VII medium temperature nitric acid and type VIII medium temperature high-concentration nitric acid solution.
Generally speaking, I heavily endorse AMS2700 Method 2 which uses citric acid and is relatively free of danger associated with heated nitric acid baths.
NOTE.
As a 'field expedient', I sometimes recommend applying Pasa-Jell 101 per USAF T.O. 1-1-691, in-lieu of typical passivation treatments that are simply not available in the bare base environment.
Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true.
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RE: Passivated Per QQ-P-35C,type 11
Can you tell us the reason you are using this spec for passivation? Does your application involve some legacy hardware that calls out this process? This is a common situation and there are actually still a few vendors that work to this spec.
RE: Passivated Per QQ-P-35C,type 11