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Chemical Ratios for QQ-P-35 Passivation of Stainless Steel

2003

We want to develop a small in-house passivation process to be used for limited qty parts (clinicals).
I have ASTM A967 but would like a free copy of qq-p-35 so we can get the chemical concentration numbers. We already have a lab being used for electro polish development so the equipment is in place to use for small quick batch process of passivation.

Are the volume % based upon 100% Nitric Acid or are they in ratio to the commercial available 70% solution you purchase from the distributor?

Eric Harmony
medical instruments - Woburn, Massachusetts

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QQ-P-35C can still be freely downloaded [not verified, the site was down] at the Defense Department's ASSIST site (http://assist2.daps.dla.mil/quicksearch/). When last checked, it was identical to SAE's QQ-P-35C [link is to free spec at Defense Logistics Agency, dla.mil].

The volumetric concentrations are based upon the use of 67 wt% HNO₃, Technical Grade Nitric Acid (not 70 % reagent grade). Same forASTM A380 & A967.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2003

Both the DOD QQ-P-35C [from DLA] and the AMSQQP35 [canceled] have been canceled and are no longer specifications to be used for passivation.

QQ-P-35c is replaced by ASTM A967 except for aerospace, which should use AMS2700B (replacement for AMSQQP35 [canceled]).

Commercial citric acid formulations are an alternative to the nitric formulations.

Lee Kremer
Stellar Solutions, Inc.

McHenry, Illinois

2003

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I just checked for the latest revision for AMSQQP35 [canceled] And the SAE website is still showing Revision: MAY 1998, I can not find where this has been (Canceled and replaced with AMS2700 B) can you please let us know where we may find this information?

Thank you,

Jim Denton
Anodizer - Elkhart, Indiana
2003

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AMSQQP35 [canceled] was canceled in April of 2003 by SAE/AMS Committee B, reconfirmed in the September meeting. It was canceled in favor of AMS2700.

Lee Kremer
Stellar Solutions, Inc.

McHenry, Illinois

2003

Most of my suppliers have their own standard of passivation process and they are not certain whether they conform to the AMS2700 B standards. What must I ensure that exist in the passivation process of my suppliers before I declare that it is within the AMS2700 B standards.

Masrurah Marzuki
- Singapore
2006

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As others have mentioned in this thread, when QQ-P-35 was cancelled it was replaced by ASTM A967, and by AMSQQP35 [canceled] for aerospace jobs; AMSQQP35 was then replaced by AMS2700.

My follow-up question to this is, when specs on a print for non-aerospace jobs call out QQ-P-35 Type II (or any other Type), is there any requirement to process by any particular way within ASTM A967, or can ANY process in ASTM A967 be used?

Erik Kafarski
- Madison Heights, Michigan, USA
April 15, 2010