Summary for bright acid copper adhesion issues Discussion
Bright acid copper adhesion issues are described by a plating shop that sees parts look fine coming out of the acid copper bath but scrape off after being dumped into a box. The nickel underplate from three different nickel baths appears sound, and the problem has worsened over about a month after an anode change six months earlier. Dominik Michalek advises first verifying pre-cleaning and additive addition, then checking bath chemistry with a Hull Cell and considering carbon treatment and dummy plating. Guillermo Marrufo says that if the copper is soft and stress-free yet still scrapes off, the issue is likely a true adhesion failure, not copper stress; he recommends confirming the nickel is not failing, ensuring parts enter the copper wet and live, checking busbar contact, and looking for contamination in rinse tanks, especially oil films. A later reply suggests organic/dye contamination, batch carbon treatment, and checking activation dip and copper metal content.
Q. We are an electroplating job shop in MN. We have been experiencing poor adhesion on parts coming out of our Acid Copper bath. There is no blistering and the nickel going in (from 3 different nickel baths) all looks good and has great adhesion.
The racked copper looks OK immediately after coming out of the bath, but after gently dumping the parts into a box, it scrapes off. We have not changed amperage or chemistry recently but changed anodes about 6 months ago. We have been experiencing this issue for around 1 month, and it is progressively getting worse.
Do you think this is anode or chemistry related?
Paul Magnan
Plating Shop Manager – Isle, MN, USA
January 13, 2010
 | A. Hello, are you really sure about the good cleanliness of the parts prior getting plated? What about your additives, how they get added? Suggestion: 1) Review Pre-treatment Best regards, Dominik Michalek A. Acid copper, when it looks good is very soft and stress free. The only reason it can scrape off a nickel plated surface as you describe is an absolute lack of adhesion. First, make sure the nickel underplate is not coming off too. If not, it must be a passivation and/or cleanliness issue. Make sure the parts enter the copper wet and live. Check for good contact with the busbar and check your rinse tanks, specially oil floating films. Guillermo Marrufo A. Hi, It seems that the bath is contaminated by organics and dyes, I would suggest it have a batch carbon treatment, or check on the activation dip after the copper plating, may be add some hydrogen peroxide Next check the content of copper metal.
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A. Hello Paul,
When I saw poor adhesion concerning acid copper, I had a bad electrical contact onto the cathodic bar or/and the hook. So, I suggest you to clean cathodic bar/contact and check electric circuit.
You can have an organic pollution due to nickel brighteners overdose, you can check this option if you have problem to run chrome after this nickel plating.
Hope it can help you,
Nicolas Duthil
– Bordeaux, FRANCE
A. It is very common this problem, which I can recommend is to use phosphor copper anode and verify that this in 80 ppm chloride ion and thus ensure good ductility and of course it is important to clean and rinse cycle
Oscar Villalobos
– Guadalajara, Mexico
March 2, 2010