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Clear zinc vs. electroless nickel ... a conductivity question

Hello,

Is there any real difference in the conductivity of part that has been plated clear zinc vs. the same part being plated electroless nickel? If so is there a formula/chart that shows this type of information for differing types of plating?

Tim Shinn
buyer - sheetmetal fabricator - Portland, Oregon
October 14, 2009

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October 14, 2009

Hi, Tim. There is a huge difference. Zinc is a sacrificial plating which is designed to corrode and the corrosion products will definitely interfere with conductivity if this is a low voltage electrical contact application. Most low voltage contacts like in "chargers" are electroless nickel plated, although ground screws in 115VAC circuits are zinc plated.

Electroless nickel, too, tarnishes and while it is acceptable for that kind of contact, only precious metals (like gold) will do for really low voltage digital signals.

Regards,

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

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I interpreted your question different from Ted. I see his answer as in response to "contact resistance". I read your question about "conductivity", in which case the conductivity of the "part" (you did not tell us what kind of metal but it doers not matter) will not be affected by the top coat plating - but again, as Ted says, the contact resistance will be very different.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

October 16, 2009