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Stripping hard chromium from AISI 410

Hi, my name is Carolina De Fazio. I work for an aeronautics company. I need to strip Hard Chromium Plating from a tube made in AISI 410. We strip the plating by grinding by on the surface (external diameter) we noted some chromium traces. Our Chromium subcontractor told me that it is possible to strip these traces chemically. I am not sure and I would like to find a applicable specification for reference.

Bye

Carolina De Fazio
student - Novara, Italy
July 11, 2008

Yes it is possible, but it may not be legal. You need to conform to OEM requirements or their overhaul requirements. Also, there may be national agency requirements.

James Watts
- Navarre, Florida
July 11, 2008

I fully agree with Jim. Just to give you some theoretical info. Hard chrome can be stripped by immersion in hydrochloric acid or by a reverse (anodic) treatment in a solution of sodium hydroxide in water. The wastes generated will be toxic and regulated. Also, any of these processes must be authorized by the end user as there may be potential adverse effects on the substrate material.

Guillermo Marrufo
Monterrey, NL, Mexico
July 15, 2008

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The 410 stainless will be attacked by hydrochloric acid, so you seem to be left with the electrolytic process as the only acceptable method.

Bill Reynolds [deceased]
consultant metallurgist - Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.
July 17, 2008

I have stripped chrome off of 410 lots of times with a 20 to 25% by volume solution. It works well if you do not get any copper in it. Eventually, if you overuse it, ferric chloride [on eBay or Amazon] builds up and that will pit the part. So, when it starts to discolor, find some other use for it.

James Watts
- Navarre, Florida
July 17, 2008