Peeling Copper

Question:

How do you plate steel parts with copper? Given the difficult economic times, we took on this job assuming that it would be easy to do.It has given us a lot of grief! The major problem is peeling. Any suggestions? N.N.

Answer:

In order to successfully plate on copper, youmust first apply a strike to the surface. There are a couple of processes for doing this. One method is to use a Wood’s nickel strike. After the strike, the part is placed in a copper sulfate plating bath andplated. You should go in “live,” whichmeans that as the part is immersed, deposition will start immediately. Someplaters use a lower current density when first immersing the parts and then increase it once the entire rack is immersed.

Another method is to use a Watts nickel plating bath as a strike bath. The Watts bath will allow you to apply a thicker strike layer. The advantage of a thicker nickel layeris that it will be less porous than thethin layer obtained from the Wood’snickel bath. This in turn means thatthe steel part is less likely to be attackedwhen first immersed in the acid copper bath.

One last comment: Your e-mail doesn’t state the type of peeling you are experiencing.If the peeling is from the nickel strike layer, then you should determine whether the nickel is going passive on you prior toimmersion in the acid copper bath. If thecopper layer appears to have whitish material on it, then the peeling is from the substrate. If this is the case you must review your cleaning process prior to the strike.