Daniel

Topic: Nickel peels off

I'm facing trouble with a copper part (phospor bronze)Nickel peels off after one day or two the treatment is nickel plate in watts bath, part made of sae65 copper alloy. It rusts in the same place on all the parts and when the nickel is removed you can see the bronze.

Need help!

Thanks


   pieza (Large).JPG

Last edited by Daniel (03/11/2011 - 12:41 PM)

DustinGebhardt

Re: Nickel peels off

Poor adhesion is almost always related to pretreatment.  And if you say that there is a dark spot on the part, this maybe be a problem with the part itself  It may have a bad spot in the alloy.  This bad spot may  not react well with your pretreatment process, causing poor adhesion.  Looking at the SAE65 spec, there is a minimal amount of phos in the alloy. It is primarily copper and tin.  The next two items are nickel and lead, with a max of 0.50% each.  Both of these are very stubborn when it comes to adhesion.  Lead likes to be activated with a fluoride-containing acid.  Nickel as well. Nickel also does will with a reverse current in the bath. 


I would suggest that you adjust your pretreatment and go from there.

-Dustin Gebhardt, CEF

Advanced Manufacturing/Finishing Engineer

Moen

Sanford, NC

99

Re: Nickel peels off

bad cleaning

bad preperation

vat contamination