Aloha, fun & authoritative answers -- no cost, no registration, no passwords, no popups
(as an eBay Partner & Amazon Affiliate we earn from qualifying purchases)

Where the
world gathers for metal finishing
Q&As since 1989

-----

Yellow chromate versus clear chromate

I am using a sheet metal part with a plating for a 70 °C application. Am I better off using clear (zinc, I think) chromate or yellow chromate? I have heard conflicting stories as to whether clear chromate can handle the temperature. Since cost is an issue, I would like to use the clear chromate coating if it will stand up to the temperature without turning to powder.

Don Dziubakowski
mfgr - Seven Hills, Ohio, USA
2004

Are you referring to zinc plated steel followed by a chromate conversion coating? If so, chromates clear or yellow will not retain its protective properties when exposed to 70 °C for a period of time. The coating dehydrates and cracks. If no zinc plating a chromate conversion coating will not work on steel. If you are inquiring about a zinc-zinc chromate primer, this will work at 70 °C.

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

(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: