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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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LAMINAR LAYERS IN BARREL NICKEL PLATING
We do Nickel plating over SS 303 following a wood's strike (240 g/l NiCl2 & 125 ml/l of HCl). It's Barrel process. After Plating when we do tape test, we see the nickel film peeled off from the part along the tape and also one more nickel layer seen on the surface. It seems that two lamellae nickel deposit occurred during the process. Can any one help me to solve this problem.
Thanks and Regards,
Connector Manufacturer - CHENNAI, Tamil Nadu, India
2004
Wood's nickel is used to activate stainless steel, but it is very prone to going passive itself. Are you going immediately from the nickel strike to nickel plating with just a very quick rinse?
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004
Thanks Mr. Mooney for your response. We do nickel plating immediately after wood's without any delay. I mean the other layer also looks bright. These two layer would have formed only in the bright nickel, it seems. I read in an article that any intermittent current flow may cause this problem, and again I am not sure, since it is not happening in all the batches and also I don't know how to measure that.
Regards,
Connector Manufacturer - Chennai, Tamil Nadu and India
2004
2004
Based on your update and a re-read of your question, I would agree that you are suffering current breaks. Make sure the dangler connections are tight and that the V-saddles for the barrel are scrupulously clean and see if the problem goes away.
If not, I still suspect a sporadic current break which can be tracked by rigging up 12-volt light bulbs or other measures.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Sounds like either a faulty or dirty connection in the power supply. Check and clean all your power contacts, especially those between the buss bars and barrel. It is also possible that the barrel is incorrectly loaded or, for some reason, the dangler is not making adequate contact.
Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2004
2004
The condition that you refer to has been named by some as the
"Onion Skin," effect. With this effect, you get nickel on top of nickel on top of nickel layers many times on your part.
While any of the above cures might work, one that has done well over many years, is to simply slow down the speed of the barrel. Many platers use 4 - 6 revolutions/minute. However, experimentation with
2-4 revolutions/minute could yield a finish that does not have the layers of nickel that you describe.
Finally, check to see that your Boric Acid is at the suggested level in your bath, for the necessary buffering action needed by your system.
Ed Budman [dec]
- Pennsylvania
With deep sadness we advise that our good friend Ed passed away Nov. 24, 2018
Q. Hi,
This is Kerem from Turkey. I am working at electroplating process at the moment. We have kind of plating problem right here. I hope there are some people who can help us here :D.
We are making production of bright nickel process with barrel. We charge average 2500 pieces (each piece 12.9 grams) product to barrels every 10 minutes. At first, we are plating to metal with copper then after plating with nickel. But one of the our products double nickel plated at every cycle. I absolutely know that is not ocurring from the electricity. We cannot find reason of that. Perhaps you guys could help me about it?
Best Regards
Kerem
- Turkey
January 11, 2014
A. Hello Karem,
Is your question, why are you getting twice the normal nickel plating thickness on one of your product runs? Is this particular product processed by itself in the barrel? Please be more specific so we can help you.
Process Engineer - Malone, New York, USA
January 15, 2014
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