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Ted Mooney, P.E. RET
Pine Beach, NJ
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Testing for Iron Concentration of Passivation BathAMS 2700
Q. I am a Special Processes Manager. I am looking for testing procedures for Iron Concentration in a Passivation bath IAW 3.1.2.2 of AMS2700. I am running a Type 2 Nitric Acid Bath. Any information would be helpful.
Thank You for your time.
Special Processes Manager - Chattanooga, Tennessee
July 6, 2010
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A. I would recommend ICP analysis Terry Tomt- Auburn, Washington July 8, 2010 A. Hi, Mike. Flame Atomic Absorption ⇦this on eBay or Amazon [affil links] is the way to go. If you don't have an AA, send it out to a local lab.  Jon Barrows, MSF, EHSSC GOAD Company  Independence, Missouri  July 8, 2010 |
Thanks for your responses. The info was very helpful.
Q. Can the Iron Concentration be adjusted if so how?
Thanks for your time.
Aerospace Special Processing - Chattanooga, Tennessee
July 19, 2010
AWWA
on AbeBooks
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Amazon
(affil links)
A. You could also do it colorimetrically, via the 1, 10 phenanthroline method. See
<== 'Standard Methods ...'.
Dave Wichern
Consultant - The Bronx, New York
July 20, 2010
A. I just finished setting up a method for this in our lab using a modified method from Hach on our little spectrometer we have. The problem I ran into with the passivate II solution is the possible interference with the chromium in solution, but if you dilute it well enough, the interference is negligible.
I believe that AMS2700 calls out for the solution to contain less than 0.5 w/w% iron. If it gets close to this level, I suggest you just dump the bath and make a new one.
The other methods suggested are more accurate but if you have a Hach spectrometer, it is a little more cost effective.
Geronimo Cebrero- Oxnard, California
July 29, 2010
A. Hello,
Read Letter # 39558 - very helpful.
Micheline Forth
finisher - Rincon, Georgia, USA
August 2, 2010
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