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Stripping Copper-Nickel-Indium alloy

Can anyone advise please as to the best way to strip copper-nickel-indium flame plate?
Is chemical stripping the best method or should I employ an Electrochemical stripping method?

Nigel Gill, BSc MRSC MIMF
Aerospace. - Glasgow, Scotland
February 22, 2009

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You fail to say what the parent metal is, or did I miss it. That makes a difference.
Since you are Aerospace, you have to use whatever the OEM says that you can use as well as how to use it. Any buddies at RR that might be willing to help?

James Watts
- Navarre, Florida
February 25, 2009

Parent material is Titanium...any help would be very much appreciated.

Nigel Gill, BSc MIMF MRSC
Aerospace. - Glasgow, Scotland
February 26, 2009

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February 27, 2009

That is a tough one, but at least the parent metal being Ti is some help.
I would contact Metalx (Ronatec.us) [a finishing.com supporting advertiser] to see if they have any ideas. They are a tiny company, but used to be great people. I have no current knowledge.

I would also look at a couple of text books. Probably Canning and "Modern Electroplating" [adv: this book on AbeBooks, eBay, Amazon] , edited by Lowenheim has an extensive section on strippers.
Since this is thermal deposited, it is not going to be a true alloy, but an alloy and a mixture. I would try to attack the primary component, which I will guess is nickel. Copper uses nasty compounds to strip and indium is very difficult to attack. You may have to strip a while and then grit blast it and re-strip, possibly several cycles.
Watch out for chlorides, as some OEM's have heartburn about chloride content in rinse water. (one that does still uses a good amount of HCl in one specified strip).

Sounds like lots of test coupons for your lab to play with.

James Watts
- Navarre, Florida