electrically resistant

[Akronplating]

Does anyone know a good plating finish for electrical resistance? It is for an item used as an electrical insulator. Thank you.

[sswee]

What is the base material?
SS

[engineerscott]

Originally Posted by Akronplating

Does anyone know a good plating finish for electrical resistance? It is for an item used as an electrical insulator. Thank you.

I'm a little confused about what you are asking for. Do you want the plating to be electrically conductive or do you want it to be an electrical insulator.

If you want a conductive plating, you're in luck. All metal electroplates are conductive. Of the common metals you might plate with in order of best to worse conductors the list would be - Silver, Copper, Gold, Aluminum, Bronze, Brass, Zinc, Nickel, Chromium, ..... However, pure bulk resistivity is not necessarily the most important issue. If for example you are trying to make an electrical contact that is exposed to air and subject to oxidation or corrosion then you must take the metal's other properties into consideration. For example, silver is the most conductive metal on the list. However, anyone who has seen their mother's silverware knows that silver oxidizes on exposure to the air. The oxides and sulfates of silver are very poor electrical conductors. This is why most non-sealed switch contacts don't use silver for the contact surface. Gold on the other hand forms almost no oxides when exposed to air (or almost anything else for that matter). Therefore, good quality switch or connector contacts are often plated with gold (a very thin layer (<10 microns) thick is all that is required so the cost is fairly low). Some bronzes (often phosphor bronzes in particular) are used on electrical contact surfaces where cost is a big issue or you have contacts that carry high current and operate at high temperature. Nickel is also used since the oxide layer it forms is very thin and easy to break through.

If on the other hand you want a plated surface that is non conductive then you are pretty much out of luck. Metals (by definition) are good electrical conductors. What you'd want to look at instead is probably a powder coat (which comes in clear and colors). This is basically just a layer of plastic on your finished item. A powder coat finish will provide decent insulation against low voltages (say <60V). At higher voltages small imperfections in the powder coat finish can break down and allow an electrical discharge through.