No registration or passwords; no pop-up ads -- just aloha, fun, & answers.
(as an eBay Partner & Amazon Affiliate earns from qualifying purchases).
Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Advertise
 
Help
Wanted
Current
Q&A's
Site 🔍
Search
pub  Where the
world gathers for metal finishing
Q&As since 1989



-----

Zinc Chromate Corrosion caused by insufficient cure time?




We manufacture Electrical Connectors and are having a corrosion issue with some Copper Terminals that are Zinc Chromate Plated at an outside vendor. We bring them in house and take them right to the assembly line (into plastic housings), within hours of receipt. Within 24 hours we have corrosion on the surface of the Terminals as we moisturize the assembly for customer use. Could we be using these Terminals too quickly before they are cured or are we looking at the wrong thing? These parts are fed via feeder bowls into position for assembly into the plastic housings and our thought was the edges of plating could be disrupted by this action creating thin areas in the plating.

Bob DeRoss
Product Designer - Pinellas Park, Florida
2007



2007

Bob,

Usually the hexavalent chromate gets its hardness after 48 hrs. I wonder if you are using trivalent or hexavalent. Yo should check with your plating supplier how long time it takes to get a resistant chromate surface. And if the temperatures you use afterwards, in the plastic injection process are adequate for the chromate.

Saludos

Guillermo Castorena
Jobshop - San Luis Potosi, Mexico




(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:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"