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Chemical ratios for QQ-P-35 passivation of stainless steel

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We want to develop a small in-house passivation process to be used for limited qty parts (clinicals).
I have ASTM A967 [link is to spec at TechStreet] 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-35 [link is to spec at TechStreet].

The volumetric concentrations are based upon the use of 67 wt% HNO₃, Technical Grade Nitric Acid (not 70 % reagent grade). Same for ASTM ASTM A380 [link is to spec at TechStreet] & A967.

Ken Vlach - Goleta, California

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Both the DOD QQ-P-35C [link is to spec at TechStreet] and the AMS-QQ-P-35 [link is to spec at TechStreet] have been canceled and are no longer specifications to be used for passivation.

QQ-P-35c is replaced by ASTM A-967 except for aerospace, which should use AMS-2700 [link is to spec at TechStreet]B (replacement for AMS QQ-P-35).

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

Lee Kremer Stellar Solutions, Inc. McHenry, Illinois

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I just checked for the latest revision for AMS QQ-P-35 And the SAE website is still showing Revision: MAY 1998, I can not find where this has been (Canceled and replaced with AMS 2700 B) can you please let us know where we may find this information?

Thank you,

Jim Denton
Anodizer - Elkhart, Indiana

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+++ AMS QQ-P-35 was canceled in April of 2003 by SAE/AMS Committee B, reconfirmed in the September meeting. It was canceled in favor of AMS-2700 [link is to spec at TechStreet]. Lee Kremer Stellar Solutions, Inc. McHenry, Illinois ++++++ Most of my suppliers have their own standard of passivation process and they are not certain whether they conform to the AMS-2700 [link is to spec at TechStreet]B standards. What must I ensure that exist in the passivation process of my suppliers before I declare that it is within the AMS 2700B standards. Masrurah Marzuki - Singapore April 15, 2010 As others have mentioned in this thread, when QQ-P-35 was cancelled it was replaced by ASTM A 967, and by AMS-QQ-P-35 for aerospace jobs; AMS-QQ-P-35 was then replace by AMS 2700. 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 A 967, or can ANY process in ASTM A 967 be used? Erik Kafarski - Madison Heights, Michigan, USA ANSWER or FOLLOW UP POST an unrelated QUESTION HOT Topics