Poor Adhesion of Nickel Plating on Neodymium

A. Hi JM,
There are many possible causes for poor nickel plating adhesion. I doubt that lack of brightener actually reduces adhesion, but highly stressed brittle plating can manifest/masquerade as poor adhesion.

But we need at least some general data or we're flailing in the dark. Is this barrel plating (make & break contact can cause it)? What is the substrate (stainless, aluminum, diecast, & leaded substrates require special pretreatment)? Have you successfully plated this exact part with this process before? Is there any possibility that silicones have found their way onto the parts (they're almost impossible to remove)? Is the adhesion problem exactly at the interface between substrate and plating (any flakes with only nickel both top & bottom)? Thanks.

Luck & Regards,


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

Q. Good day Sir Ted.. thank you for replying immediately. And my apology for the lack of information. To continue, we are doing barrel plating wherein substrate is Nd Magnet. On its plating line, there are 2 solutions Cu and Ni. And using Cu / Ni process we are not encountering such issue, only on Nickel coating. And flaking happens between the substrate and plating layer. Currently this is plated in plating line together with Cu / Ni Process.. For Cu / Ni Process there is no occurrence of flaking after 250 °C x 10 mins.. Only Ni process has such problem (both of them also has the almost same level of plating thickness). We have other plating lines also with Ni / Ni / Ni process.. Main component is same from plating line with problem except for the Brightener (or additives).. so I thought that could be one of the possible problem. Thank you... JM Riveral [returning] - Cavite Philippines November 18, 2023 A. JM, The nickel layer adhesion problem 1) If adhesion between base metal and nickel layer-have cleaning problem 2) nickel to nickel peel may be bipolar condition or transfer tank to tank too late or part dry. 3) check the current problem. 4) check anode (nickel metal in baskets) level too low popat patel consultant/chemist - Roseville November 22, 2023

Q. Hi. Thank you for your reply.
I would like to respond and check your response.
The nickel layer adhesion problem
1) If adhesion between base metal and nickel layer-have cleaning problem.
Response : I rule out this one. Since if the cleaning has problem (or the pre-treatment process), flaking should also happen on Cu / Ni process.
2) nickel to nickel peel may be bipolar condition or transfer tank to tank too late or part dry.
Response : Flaking is happening between Ni and Substrate (or the material)
3) check the current problem.
Response : You mean Current (Ampere) setting? Currently set to 21A by 2 Hours.. actually I'm thinking the time of processing. But I don't have any study yet.
4) check anode (nickel metal in baskets) level too low
Response : If this is also the problem, we should also encountering flaking on Cu / Ni Process..

Im actually puzzled of what to do.. Currently we try to replace the solution yet not sure if this will help eliminate the flaking.