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Electroless Nickel on Brass

June 23, 2009

Greetings,

In the past, I have successfully used our electroless nickel bath to plate copper. Yesterday, however, I tried plating some small brass cylinders, and I was unable to deposit EN on the surface. I put the parts through an alkaline soak clean, an acid activation step (proprietary blend, but I know it was formulated for ferrous materials), and a DI rinse. Then I put the parts in our mid-phos bath at 190 F. Nothing.

Can anyone suggest a different surface prep or an additive for the EN bath to kick off the plating?

Thanks,

Michael Costello
Plating Engineer - Grand Junction, CO, USA

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June 23, 2009

Hi, Michael. How about kicking off the plating with a quick jolt from a rectifier?

Regards,

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

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June 25, 2009

Ted,

Thanks for the advice. Would this mean racking up the EN bath to accommodate current? If so, how much and for how long?

Is electrically kicking off the EN reaction better than coating over an electrolytic nickel strike?

Thanks,

Michael Costello
DOD Primary Contractor - Grand Junction, Colorado, USA

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June 26, 2009

Hi, Michael. I wouldn't say it's better, but it's a lot easier since it's very quick and does not involve an extra process and extra rinsing. You just put power on the rack, perhaps with a battery cable connected to a rectifier, for a few seconds. I guess you need something for an anode, but nothing formal.

Regards,

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

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First of two simultaneous responses --

Michael,
You can kick start EN plating on copper alloy by using a 9 volt battery. Negative wire touching your rack or part, positive wire inside the EN solution.5 to 10 seconds is all you need. Touching your part with a catalytic material like steel with also kick start plating. Good Luck.

SK Cheah
- Penang, Malaysia
June 29, 2009

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Second of two simultaneous responses -- June 29, 2009

Dear sir


Please put one or two MS parts along with Brass parts

Suresh Reddy
- Bangalore

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Hi Michael!
EN plating is a auto catalytic process, it must only start and then its go;
When I have problems to start the EN plate on brass or copper, I use a little part in steel (normal pretreated)and contact this with the brass or copper parts and all start simultaneously.
It is a easy way; The steel start with the different electric potential between iron and nickel and brass or copper touched with steel became this potential like a electric Kick and start to.

Franz R Wagner

Franz R Wagner
- Blumenau SC Brazil
July 9, 2009