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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Nickel plating is black and brittle
Q. I am a chemical engineer. I am plating Rack Brittle Nickel. There is problem burning and dark in my work. Hull Cell is attached:
...and analytical values Ni 55 g/l, Cl 44 g/l, boric acid 50 g/l.
Asmaa Ismail- Alexandria egypt
February 22, 2023
A. Hi Asmaa. That doesn't look like a Hull Cell panel to me since it looks quite uniform across the entire current density range from minimum to maximum :-) Are you sure that panel was plated in a Hull Cell and at usual current (1 or 2 Amps)?
That analysis sounds like you are trying to plate in an all-chloride bath, which I am unfamiliar with, but which I understand is used only in very special situations because it produces very brittle and highly stressed plating. So I'm not really confident that I am understanding your question or your situation :-(
You are trying to plate the nickel brittle?
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Q. Thanks for your reply Mr. Ted
Yes, plating a brittle Nickel
Hull cell is worked at 2 Amps for 2 minutes
- Egypt
March 14, 2023
A. Hi again Asmaa. I'm not seeing the burning you report, with the possible exception of the extreme high current density edge where it would be expected even in a nearly perfect bath.
Although it's a little hard to judge 'darkness' without brightness to compare it to, yes, it does look uniformly dark all across the current density range. I am not familiar with seeing a nickel plating hull cell panel which is uniformly dark, but have you attempted to look for sulfides?
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Q. Thanks for your help
During work, first batch looks perfect but second batch dark is appeared again as shown with attached photos
Even after carbon treatment
- Egypt
April 6, 2023
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