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How to Remove nickel plating from carbon steel
Q. I am seeking information regarding a method to strip electroplated nickel (plated from a Watts-type bath) from carbon steel. The parts could possibly have a copper strike under the nickel, we aren't sure. I am looking for a method that would be the optimum from an economical, environmental and safety perspective. Any insight would be appreciated.Thomas Kemp
- Erie, Pennsylvania, USA
TUTORIAL FOR NEWBIES:
Although most plating texts briefly address stripping, by far the best coverage of stripping that we've seen is the 22-page "Stripping of Electrodeposits" chapter by E. B. Saubestre in Lowenheim's "Modern Electroplating" [link is to info about book at Amazon].
It explains that stripping is an oxidation process from the metallic to the ionic state, which means the stripper must either be an oxidizing agent (immersion strippers), or anodic current must provide the oxidizing power (electrolytic strippers).
In addition, the stripper must not attack (or must only slowly attack the substrate), which is possible under three circumstances:
1. The metal to be stripped is more electrochemically active than the substrate, or
2. A complexing/chelating agent is employed which is more effective on the coating being stripped than on the substrate metal, or
3. An inhibitor chemically or physically absorbs on the substrate.
A. If you are not presently in the metal finishing business I would suggest you contact a job shop to strip your parts. Any strip solution which would contain nickel or copper, no matter how environmentally benign would be considered a hazardous waste because of the metals. If you are going to strip, proprietary products are available which are non-hazardous or which generate a minimum amount of waste.Gene Packman
process supplier - Great Neck, New York
(2004) -- this entry appended to this thread by editor in lieu of spawning a duplicative thread
Q. I have a old FN hi-power handgun that has had the steel slide nickel plated I am looking to restore it but need to remove the nickel in order to have it blued. Can you recommend a safe method?Joe Weinsteiger
hobbyist - Thornton, Colorado, USA
November 10, 2013 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread
Q. How do we remove nickel electroplating from iron?ahmed zain elabdeen
To minimize searching and thrashing time, and to provide multiple points of view, Finishing.com combined several formerly separate threads into the single dialog you are now viewing. Please forgive any resultant repetition.
How do I easily and cheaply remove nickel plating from forged steel?Michael R. Carroll
- Potomac, Maryland USA
Q. Dear sir,
I have a question, what type of solutions are used for stripping nickel plated mild steel? I have used nitric acid-sodium fluoride solution, but it attacks the surface. Please, tell me alternative and easiest method for stripping nickel plated articles.
I am doing Ph.D in this area, please help me.Thanga Raj. V
National Institute of Technology Karnataka - Mangalore, Karnataka, India
A. Dear Michael,
Nickel is metallurgically quite similar to iron, but more corrosion resistant, so it isn't necessarily easy and cheap to remove nickel from iron. The best and most environmentally friendly choice might be to use a proprietary nickel stripper, such as offered by Metalx [a finishing.com supporting advertiser] rather than using a nitric acid based or cyanide based stripper.
Since you are doing a Ph.D in the area, you should make every effort to locate a copy of "Modern Electroplating" [link is to info about book at Amazon]. The 22-page chapter by E. B. Saubestre on "Stripping of Electrodeposits" explains everything with remarkable clarity, and includes 59 references. Best of luck.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
A. The best solution for removing the nickel is: 1.2% Hydrogen peroxide + 15% Nitric acidNina [last name deleted for privacy by Editor]
High temperature electrostrip formula?(2003)
Q. In the late 50s I discovered a public domain electrostrip for nickel from steel. This had been developed by General Motors, and basically contained mainly Sodium Nitrate, a smaller percentage of Sodium Nitrate, and I think Sodium Hydroxide. Processing bath temperature was about 160 °F, and it was necessary to keep the pH within a certain alkaline range. It was necessary to add about 1/2 gallon of Nitric Acid per shift to achieve this. The stripping action produced a foam and sludge, probably a nickel hydroxide, as the nitric additions would redissolve the sludge.
The current density needed to be higher than 80 Amps/ft2, otherwise we could experience etching. I had reasonable success using this system, the application being on the recovery of rejected tubular steel furniture components. The stripped surface was absolutely clean, and could be returned to nickel plating without any further intervention. Problems did occur if the sludge deposited on the stripped surface causing deep pitting.
At present we are running a proprietary electrostrip, which has all the same characteristics, except that we cannot run it above 110 °F, as it contains an inhibitor which it is claimed is unstable above that temperature. As the high current density generates a great deal of heat we need cooling on this tank. Needless to say we experience great problems with etching and pitting of stripped work, mainly motorcycle exhausts and crash bars. Does anyone out there perhaps have the original General Motors simple formulation sans inhibitors?Raymond S [last name deleted for privacy by Editor]
- Los Angeles, California, USA
Stripping Sulfamate NickelNovember 5, 2011
Q. I'm on my last straw. I have some very important parts from a customer of mine that required sulfamate nickel plating. As the job progressed, (16 pieces total) we found that 6 of them had blisters and had to be stripped and replated. The substrate is ASTM A514 grade Q steel and there was between 0.0015" and 0.0025" of sulfamate nickel plate on them. I have tried stripping them in a proprietary stripper, nitric acid, and the stripper recommended in the Metal Finishing Guidebook (600 mL/L sulfuric acid and 30 g/L copper sulfate run at 6v anodic current) -- and they all have not seemed to have dented the nickel. The sulfuric acid stripper with the copper sulfate has done the most progress but it is still very slow. We have also tried to blast the parts with glass AG, and aluminum oxide but that only seems to matte the surface appearance and not pull any nickel up. ANY other tips or tricks would help greatly! Thank you in advance.Geronimo Cebrero
Chemist - Oxnard, California, USA
November 10, 2011
A. There are numerous nickel stripping solutions, including one that uses concentrated sulphuric acid (50+Be); make the workpiece anodic and a current density of at least 5 A/dm2.
Also try an alkaline solution of sodium or ammonium nitrate and a current density of over 5 A/dm2.
R&D practical scientist
Chesham, Bucks, UK
November 11, 2011
A. There are numerous cold nickel strippers. There is one called "B-9", marketed by Metalx [a finishing.com supporting advertiser] that should do the job.
There are also a number of public domain cold Ni strippers based on m-nitro benzene sulfonate/ethylenediamine. A formula for one is (or used to be) in the Metal Finishing Guidebook. If you don't have luck with the current issue, go back a few years and you will find it.
Final note: DON'T mix either spent stripper or stripper rinse with anything else, or try to "trickle it in" to your waste treatment system. It's like grim death, that stuff. Strictly segregate it and evaporate it; then, mix the residue in with your solid waste.
Consultant - The Bronx, New York
February 1, 2014 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread
Q. Anybody know how to prepare NICKEL STRIPPER for Mild steel?ARUN YOGESH
- MUMBAI INDIA
Ed. note: As you see, Arun, we've appended your inquiry to a thread which already addresses the issue. Good luck.
December 28, 2016 -- this entry appended to this thread by editor in lieu of spawning a duplicative thread
Q. I have nickel plated parts per QQ-N-290 but there is base metal exposure and nickel plating peeled off. So whether we can do rework of these parts and per which standard. Can anyone suggest me how to do rework with reference to spec?RAJENDRA NINGEGOWDA
- Bengaluru India