Mr. Rogers: "Look for the Helpers. You will always find people who are helping."
As an Amazon Associate & eBay Partner: we earn from qualifying purchases

finishing.com -- The Home Page of the Finishing Industry

Thread 571/16

Green corrosion on silver plating

Hi, I make copper inductance coil out of of copper tubes by coiling them into a spring shape form and the tube ends are then soldered and sealed, thereafter silver plated per ASTM -B-700-97 class D semi-bright. Occasionally there are chemical attacks on the silver which form a layer of green color oxide which is only noticed after several days. How can we prevent this from happening?

James Lee
- Singapore
May 6, 2011
publicly reply to James Lee

Copper and silver plated on each other or clamped together will migrate into each other, cuprous oxide is green.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

First of two simultaneous responses -- May 6, 2011
publicly reply to Robert H Probert

It is probably migration of the copper to the surface.
How many microns of silver do you plate?

Try a barrier layer of nickel between the copper and the silver.

Sara Michaeli
Tel-Aviv-Yafo, Israel
Second of two simultaneous responses -- May 8, 2011
publicly reply to Sara Michaeli

(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories: