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AMS 2410 silver plating problem
Q. AMS2410, silver is peeling from sulfamate nickel underplating after inert atmosphere bake. Process is both rack and barrel. Media is used in barrel plating. Parts are Inconel 718 fasteners.
Any recommendation regarding cleaning and activation or special conditions for the process plating baths?
Plating shop GM - Bell Gardens, California
2007
A. Old nickel is hard to activate! You need to proceed from the nickel rinse tank to the silver strike tank with all due haste or the nickel will passivate and the silver will separate in the oven. It beats trying to activate the nickel. Someone will suggest a Woods Nickel Strike, but that will also be hit or miss to the sulfamate nickel and still will need to move with all due haste to the strike tank. You are using a silver strike aren't you? If not, no wonder that it will not stick.
James Watts- Navarre, Florida
2007
A. Hi George,
I would need more info regarding the process line before giving you a good answer. How much time is there between Ni plate and silver plate? Most likely the Ni is becoming passive, although not real common if platers are working with a potassium silver cyanide solution. Cyanide aids in keeping the surface of the underplate active. Is there a silver strike bath on the plating line? There are proprietary Ni activators available but if the plater is going from nickel right into silver (with proper rinsing of course) you really don't have to employ a nickel activator. Look forward to hearing back from you soon.
Process Engineer - Syracuse, New York
2007
Q. Is an electroless nickel strike acceptable to use under the silver plate per AMS2410?
Cliff Hufstedler- Warm Springs, Arkansas, USA
October 14, 2014
A. Hello Cliff,
The question you asked was in October? I just saw it posted on Dec 3rd. I also responded to the question on Dec 3rd, but my response did not post for some reason. A "Nickel Strike" is considered an electrolytic not a autocatalytic plate process. I have plated a lot of EN, but have never heard of a EN strike. You could mimic the same deposit thickness in EN, but would it have the same benefits as a true Woods Ni Strike? In most cases I doubt it. Is your base metal able to be activated for EN, such as using a palladium activator for example? Do you or your plater have an EN line in place? A Ni strike is widely employed under silver in the standard specs. So the big question would be, why would you want to go into a much more expensive process when a standard Ni strike is commonplace?
Process Engineer - Phoenix, Arizona USA
December 8, 2014
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Ed. note: Sorry Mark, we didn't receive your posting of Dec 3rd, and don't know what happened to it.
Yes, Cliff's question is a very old one, but his Q. and your A. seems to be a good one to have on file for future readers.
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