Can sulfuric acid be used to remove nickel plating from aluminum?

A. Nickel can be stripped from aluminium using the Laybere solution; this a mixture of 3 parts of conc. sulfuric acid to 2 parts of water. It is used at room temperature with an applied anodic current of about 40 A/ft². Your container will depend on the size of your parts, but I see nothing wrong with a glass beaker [beakers on eBay or Amazon] if it is of the correct size. If you need something bigger, use a PVC, polypropylene or rubber lined steel tank. As far as the processing time is concerned - it all depends on how much nickel you have to remove and what the temperature is. Now that you have been told what to do for your project, go and do some experiments for yourself, but don't forget to give due reference to the sources of your information as it would be most unethical to claim the credit yourself.....

A. I doubt if it will work. It will also depend on what the aluminum alloy is.
Look at concentrated nitric acid. One notch below red fuming. Regular nitric that most people would use commercially has too much water in it. The part has to be absolutely dry when you put it into the acid. Note that it will slowly absorb water from the air and you will at some point have etched parts.

A. OK, my head was somewhere other than firmly attached to the neck. The procedure that I talked about was for removing EN from steel. My bad.

In another letter, an author talked about using 12% sulfuric acid with peroxide for removal of EN. Do not remember the substrate.

A. James, the sulfuric acid/peroxide mix is pretty potent and will take off most metals - I have used a similar formulation for dissolving both nickel and copper, but it will chew up any metal substrates if you're not careful!

A. You can use electrolytic etching -- this process is much safer than H2SO4. Slightly acidified nickel sulphate solution can be used as electrolyte, object=anode, platinized titanium or stainless steel=cathode.

Good luck!

A. You will need an ammeter to tell you the amount of current being passed. You will also need an accurate clock to tell you the time spent; I suggest a stopwatch. Your process looks basically sound, but I suggest you check with your supervisor before doing it - he knows your abilities and the abilities of your classmates and the equipment. Furthermore, he is responsible for you!

A. Hi, cousin Lee.

The dangerous part is conducting experiments except under a lab hood, or without wearing the correct PPE experiment, or without proper training and/or supervision. The dangerous part is asking someone on the internet, who you don't know and who doesn't know you or your facility or your training level, about the safety of a proposed experiment. As Mr. Crichton noted, your supervisor is the one who must be asked these questions and who must supervise you during it. Good luck, and stay safe.

A. If you want to remove the nickel from hard drive disks you cut the disks up into 1/4 inch strips and soak it in HCl or muriatic acid this will dissolve all the aluminum base metal and all you are left with is the nickel platinum cobalt alloy thin film. I do this all the time and sell the foil on eBay as a platinum alloy. there is a fast reaction at first it takes about a week for me to dissolve 60 disks at once I hope this helps.

A. You could use household bleach [adv: bleach/sodium hypochlorite in bulk on eBay or Amazon] , it works on the disk.

Thanks William and Theodorus. You folks are talking about scrapping, but in this case Lee is looking to remove the nickel coating without attacking or doing any damage to his aluminum disk.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

A. Hi all..

If you got NiCr to be strip..

you shall remove the Cr with sodium carbonate / washing soda [affil links] anodic at 3 ADM...after that, only you strip the nickel by sulfuric 60%...

To strip nickel from Aluminium disk, you need 70% dilution from 68% nitric acid by dipping process..the nickel will be remove..the fume might be a bit danger so be careful.. to create process inhibition you may add sulfuric acid at 5% dilution.. but the more you put it will slow the process..

A. Re colt nickel stripping, I have used the Brownells [affil links] solution before on a 1970s Colt Combat Commander and it took the nickel off great but didn't touch the copper under it. A 99 cent bottle of ammonia [on eBay or Amazon] took care of the copper.
I am now working on refinishing a 1914 Luger that had been nickeled and I was told the Brownell's solution won't work for that because it only works on electroless nickel.
I am now trying a solution of sulfuric acid and ammonia.
I will try and follow up with results.

A. Hi, Tommy.

I am very surprised that a solution which can strip electroless nickel is unable to strip electrolytic nickel plating. If you were successful with it last time, I'd try again before assuming it won't work. The Metalx solution will, of course, work. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

A. I have successfully stripped nickel from automotive parts which were zinc die cast in a sulfuric acid bath at full strength with an addition of GLYCERINE to minimize base metal attack. The parts to be stripped are anodic and lead anodes are used. For aluminum I suggest 50% Nitric Acid solution. Proper PPE and good house keeping measures are always important. Good luck.

A. Hi Terry. Trevor's postings were from 17 years ago so I don't know if he'll see yours and follow up, but in this context "concentrated" means 'as concentrated as possible/practical', i.e., 98% / S.G. 1.84 / Molarity 18.4.
Some people might say concentrated sulfuric acid is only 96% for some practical reasons, but when you're diluting with water that way, whether the acid was theoretically 98% or 96% really doesn't actually matter. Good luck!
I hope you and other readers are attentive to the safety warnings he repeats 3 times in the course of the discussion.

Luck & Regards,