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Silver plating process

February 26, 2010

I do not understand why silver flash is necessary ?
Also I would like to know why the flow is like this ?

10% HNO3 -> Zincating -> 50% HN03 -> Electroless nickel plating -> Copper plating -> Acid Copper plating ->

Kaustav Saikia
Quality Engineer - Chennai, TN, India

Hi, Kaustav. You've asked a bunch of questions about your process without giving us much background, so we need to read between the lines and do a lot of guessing. It sounds like you are plating an aluminum substrate? You cannot directly electroplate onto aluminum, so you must do a zincate immersion substitution process first. The range of plating that can be done onto zincate is very limited, principally either electroless nickel or cyanide copper. But telling you why you have all the various layers, when you haven't told us what you are plating or why, isn't possible.

A common reason for a silver strike is that a high concentration silver bath can immersion deposit on copper, which would be unsatisfactory. You may mean silver strike when you say silver flash. Please describe what you are plating and why before following up on any questions. Thanks!

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
February 26, 2010

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Hi Kaustav understand what your question is about using a thin layer of silver deposited by immersion to verify proper copper deposit on the aluminum surface and thus subsequently be any other deposit. I have done tests with the following method


10% HNO3 - zincate - 10% HNO3 - zincate strike-layer copper-silver (4 gms x liters of silver cyanide and potassium) - acid copper and so on.

I hope and will be useful

Oscar Villalobos
- Guadalajara, Mexico
March 9, 2010