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Electroless Nickel on Copper/Brass Material

A customer called and asked what would cause electroless nickel plating to flake off on copper or brass material, and what could be done to prevent this. Is it the cleaner or nickel strike?

Gary Dubnansky
plating inspector - Plainville, Connecticut
September 26, 2008

The problem is most likely in the cleaning and/or activation cycles. If the part is dirty or oxidized, even the Ni strike won't adhere. Ask the line operators or lab tech the last time cleaning and activation chemicals have been changed. Do a water break test on the parts if possible to ensure good cleaning of the parts. Good Luck!

Mark Baker
Process Engineer - Syracuse, NY USA
October 2, 2008

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First of two simultaneous responses --

Are the parts large enough to cause a drop in temperature of your plating bath? If so, a preheat in an oven may be required. You can also try stress relieving the nickel deposit after plating and see if that helps. Try one and then the other to identify which solution works. But it's probably just cleaning...

Ryan Rich
- Providence, Rhode Island
October 3, 2008

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Second of two simultaneous responses -- October 3, 2008

Is it "leaded brass"? Common job shop surface prep uses sulfuric acid and/or hydrochloric acid. Lead is insoluble in both and forms an insoluble salt thereafter, then after plating over this insoluble salt, it flakes off.

If leaded brass, then stay out of sulphates and chlorides, use 50% fluoboric acid to deox the surface.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

I agree with all the above replies. For 'leaded brass', I would recommend a cyanide copper strike or woods nickel strike prior to electroless nickel plating. Good Luck.

SK Cheah
- Penang, Malaysia
October 7, 2008

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Activation is NOT the problem. High chloride in nickel chloride strike will form insoluble salts on the surface which will cause worse adhesion loss. Do not use any chloride or sulphate ahead of the first strike. Use fluoboric acid on leaded brass and leaded steel.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

October 10, 2008

No one has said that it was leaded brass. So until that is answered, we are grasping at straws.

James Watts
- Navarre, Florida
October 14, 2008