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Nickel peeling off on 95% nickel material

September 23, 2011

Hello.
I am Vijay Kumar working in Quality dept. in plating shop

we are plating Nickel(Electrolytic) on 95% thin Nickel wire(Square in shape) after subjected to bending peeling is observed process is as follows.
Degreasing
Water rinsing
HCl pickling
Water rinsing
De-scaling operation
Water rinsing
HCl activation
Water rinsing
Nickel plating (Barrel method)

Vijay Kumar
Plating shop employee - Bangalore, Karnataka, India

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October 25, 2011

Vijay,
There could be a couple of reasons for your peeling. Firstly, you need to check the stress and ductility of your barrel plating solution and make sure it is producing the type of deposit you require. Secondly, it is quite possible that the peeling is due to poor adhesion caused by inadequate pretreatment. I note you are plating onto 95% nickel, so it is fair to treat the substrate as nickel. I find it is best if nickel is preplated with a high chloride Wood's nickel, followed immediately by a conventional Watts or sulphamate nickel.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK

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You probably will not like this post. Oxidized nickel is very difficult to activate.
I liked a HNO3-HF mixture and have used sulfuric-HF with a tiny anodic current The Woods strike mentioned in the previous post is mandatory!!

James Watts
- Navarre, Florida
October 26, 2011