Home /
T.O.C.
FAQs
 
Good
Books
Ref.
Libr.
Advertise
Here
Help
Wanted
Current
Q&A's
Search 🔍
the Site

World's #1 on-line resource since 1989

-----

How to calculate % of CrVI in bath to % on finished part



2002

Is there a way to determine how much CrVI is present on a finished part from one of my suppliers when the only known factor is the percentage of CrVI is in the water-based plating bath?

My supplier says there is between 0.25% - 0.70% CrVI in the plating bath.

With this information can I calculate the amount of Hex (percentage-wise) is in the plating when dry on the part?

For example: Zinc - 99% & CrVI - 1%

Can anyone shed some light on this for me?

Jeff Gerdon
- Miami, Florida, USA


2002

You can determine the thickness of the zinc metal with a magnetic thickness testing instrument several of which are advertised in the trade journals the best being the Magni-Gage.

You can determine the "coating weight" of the chromate by weighing a chromated panel, stripping the chromate and re-weighing. Detailed procedures are available.

The concentration of Hex Chromate in the solution is not necessarily directly a linear function of the resultant coating weight of the applied chromate. Other factors such as pH, temperature, time, contaminants, and even the purity of the zinc deposit which would be more pure out of an alkaline bath and loaded with co-deposited junk out of an acid chloride solution.

robert probert



Robert H Probert
Robert H Probert Technical Services
supporting advertiser
Garner, North Carolina
probertbanner

help wanted ad
Plating Shop Manager [Salisbury, MD]
Junior Quality Engineer [Santa Clara, CA]
Plating Process Engineer [Wenatchee, WA]

Q, A, or Comment on THIS thread SEARCH for Threads about ... My Topic Not Found: Start 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    -    ©1995-2021 finishing.com, Pine Beach, New Jersey, USA