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





-----

Chrome 3 vs. Chrome 6: Different coefficient of friction?


February 11, 2014

Q. Hi all,

Am encountering a friction problem and can't seem to understand where it is coming from. We have recently changed surface treatment from Cr6 to Cr3 but this has a secondary treatment which is Zn-Ni and is the same in both cases.

Does anyone think that the difference between the Cr6 and Cr3 under the Zn-Ni coating have any potential effect on the coefficient of friction of the finished product.

Any ideas?

Andy Moran
- England

A. Hi Andy. 99.9% of the time the coating sequence would be Zn-Ni electroplating followed by Chrome 6 or Chrome 3 chromate conversion coating (passivation). And even if you did electroplate Zn-Ni on top of chrome plating, again 99% of the time it would employ a chromate conversion coating on top of that.

So I am suggesting that you investigate whether the situation has been transcribed to you correctly because, while anything is possible, it sounds likely to me that the process description became confused somewhere along the line.

Please try to explain the situation behind the friction problem and I'm sure we can do a much better job for you than if it's all kept abstract and intangible. Thanks.

Regards,

Ted Mooney, finishing.com
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
February 2014




(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"