The authoritative public forum
  for Metal Finishing since 1989
  

  -----

Roughness in copper plating bath

We have a copper plating line (Hoop type) of CN bath the component is CuCN,KCN and some of brightener additive .I had problem about roughness after plating but it happened only 1 side of product (product is Alloy42 sheet ). Then I want to know the cause with product ? Is concern about pH and concentration of K2CO3 right or not? And how to avoid the defect?

Chookait J.
plating shop - Bangkok, Thailand
2004

---

Hi Chookait. If the one side that is rough is the top side, this is called shelf roughness and is usually caused by particulates that need to be filtered out. Beyond that, I'd need to know more about this one-side defect.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

---

Why do we get rough surface in acid copper bath?
How to overcome the above problem?
What is the operating condition?

Rajasekar Tank
employee - Coimbatore, Tamilnadu , India
October 16, 2008

---

October 23, 2008

There is more than one cause for deposit roughness in acid copper plating. The most common are:
Insufficient filtration
Current density too high
Copper metal bath concentration too low
Brightener concentration too low
Metallic and / or organic bath contamination
Clogged anode bags
Your supplier should have provided you with a data sheet with operating parameters for the bath. A full analysis on the bath should be done, then dummy plate at low current density. I like to start off at 3 ASF for one hour and raise it to 5, then 7 ASF for an hour each. A carbon treatment of the bath may also be in order.

Mark Baker
Process Engineer - Syracuse, New York

---

Also relation copper sulphate ⇦ this on eBay or Amazon [affil links] and sulfuric acid should be considered.

Regards

Dominik Michalek
- Mexico City, Mexico
October 26, 2008