finishing.com -- The Home Page of the Finishing Industry
Serious Education & the most FUN
you can have in metal finishing smiley

No popups, spam, registration or passwords
HomeFAQsSuggested
Books
Help
Wanteds
Advertise
on this site
FORUM
current topics
topic 9616

How is a zinc dichromate tested?

adv.   auto technology banner

2001

How is the quality of a zinc dichromate tested? If salt spray or humidity, what is the expected # of hours expected? How does a customer know if the zinc dichromate is of expected quality?

Ed K [last name deleted for privacy by Editor]
- Madison Heights, Michigan, USA


2001

Zinc platings should be tested using the salt spray test according to ASTM B117 [link by ed. to spec at TechStreet] . Exact pass-fail criteria is on a case-by-case basis, depending on your application. White corrosion specs go by what type of dichromate you are using, generally from 24 to 200 hours. Red rust specifications could be anywhere from 96 to 500 hours.

The plater should be monitoring their process closely to make sure variables such as temperature, pH, and concentration of each bath are under control. The plater should also make periodic measurements of plating thickness in mils or microns. Platers usually also have their chemical suppliers come in and do their own testing. Ask to see the plater's lab, meet the person running the lab, and see what kind of system they have to detect and correct process problems.

tim neveau
Tim Neveau
Rochester Hills, Michigan



If you have a question in mind which seems off topic, please Search the Site

ADD a Comment to THIS thread START a NEW threadView CURRENT TOPICS

Disclaimer: It's not possible to 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 may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices


©1995-2018 finishing.com, Inc., Pine Beach, NJ   -   About finishing.com   -  Privacy Policy
How Google uses data when you visit this site.