No passwords, no registration, no paywalls, no popups, no AI

As an Amazon Associate & eBay Partner we earn from affil links

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

Search our quarter-million Q&As

Home of the finishing HOTLINE since 1989

-----

Zinc migration mechanism

I wish to understand from a chemical point of view, what is the process of zinc migration.

The product:

CA 260 Brass relay terminal

underplate (2 - 4 micrometre Cu)(78 - 157 microinches)
overplate (2 - 4 micrometre Sn)
No soldering is required on this part, just welding to
another CA 260 Brass metal part.

I have consulted ASTM B545-92 which recommends Min 2.5 micrometre Copper or 1.3 micrometre Nickel underplate on metals which contain > 5% zinc to prevent zinc migration. I have received varying recommendations of what underplate of Copper is required to prevent zinc migration. Therefore if I could receive some recommendations and a description of the mechanism or where I can learn more of the process this would be of help to me.

Thank-you very much,

Andrew Ysselmuiden
- OAKVILLE, ON, CANADA

If the ASTM specification calls for copper, I guess that is okay, but it doesn't make much sense to me, since the zinc is already alloyed with copper in the brass. I would use nickel as a barrier.

Tom Pullizzi
Falls Township, Pennsylvania

Sorry! Finishing.com is temporarily Read-Only.
Ted Mooney is retiring but I have several offers to take it over.
We're working hard to make sure we find it the best new home.

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: