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How to do non-magnetic gold plating?

What are the recommendations for gold plating brass but for the plating to be considered non-magnetic? I know that normally the materials used are Cu, Ni, and then Gold. How do you test for it?

Thanks,

Randy Jew
connector manufacturer - Irvine, California, USA
2004

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The only metal from copper, nickel and gold that has magnetic properties is the nickel. The European jewellery industry has been trying to find a replacement for nickel for some years and is now using bronze (copper-tin). Neither of these is magnetic, so you may consider using that.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2004

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You need a "diffusion barrier" between the brass(zinc/copper)and the gold, otherwise in time the zinc and copper will come through an "tarnish" the brass. Typically nickel is used but since you must avoid magnetics that leaves you to the previous recommendation above or palladium. Above all, do not use silver, as it will come through the gold faster than any other metal.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

2004

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High phosphorus (10% P or higher) is non magnetic and is an excellent diffusion barrier.

Don Baudrand
Consultant - Poulsbo, Washington
(Don is co-author of "Plating on Plastics" [on Amazon or AbeBooks affil links]
           and "Plating ABS Plastics" [on Amazon or eBay or AbeBooks affil links])
2004