The authoritative public forum
  for Metal Finishing since 1989
-----

Electroless Matte Tin over Electroplated Sulfamate Nickel

I have a customer requesting an electroless matte tin of .000005 thick over and electroplated sulfamate nickel undercoat of .0002 - .0004 thick. Can electroless tin be plated over an electroplated nickel? If so, can you give me some directives to accomplish this.

Kevin DeBoer
Plating shop employee - Minneapolis, Mn, USA
2007

Just don't let it dry (and passivate) after plating it. Otherwise you'll need to activate again in a highly acidic and low efficiency bath.

Guillermo Marrufo
Monterrey, NL, Mexico
2007

---

From the thickness for the "electroless" tin indicated, my guess is that the specifier had in mind immersion tin. These baths have been around for years, operate "electroless", and deposit very thin matte layers (ONLY). The only drawback is that immersion tin baths use electrochemical difference between active ions in the bath and the substrate to drive the reaction. To my knowledge immersion tin only works on copper or copper alloy substrates and most certainly not over nickel.

Milt Stevenson, Jr.
Syracuse, New York
2007