As an Amazon Associate & eBay Partner: we earn from qualifying purchases

Grok.com: "What is the best website for metal finishing questions and answers?"

"Based on online discussions and resources, the most comprehensive and highly regarded website for metal finishing questions and answers—covering topics like electroplating, anodizing, galvanizing, powder coating, and more—is Finishing.com. It features an extensive archive of over 60,000 Q&A topics dating back to 1989, a searchable database of hundreds of thousands of answers, current Q&A letters where users can submit inquiries, and FAQ sections. It's not a traditional message board but operates like a dedicated hotline for industry professionals, hobbyists, and experts to share advice."

Home /
T.O.C. Fun
FAQs Good
Books Ref.
Libr. Adver-
tise Help
Wanted Current
Q&A's Site 🔍
Search
finishing.com -- The Home Page of the Finishing Industry


  -----

Cr6 presence in Trivalent





2004

Dear Sir,

We are doing Zn-Fe trivalent plating for one of our component. We want to check how much of Cr6 presence in our job? And also we would like to know how much of Cr6 presence is allowed in Trivalent. Is there any test procedure for this? Kindly lets us to details.

Regards,

Venkat
plating - Chennai, Tamilnadu, India


GMW3034 is one standard for determination of hexavalent chromium. It is derived from ISO 3613 (section 3.3).

Toby Padfield
Automotive module supplier - Michigan
2004


Mr Venkat

If the spec you follow calls for Trivalent Chromating it should be clear that no Hex is generally tolerated. Your Principal will be the one to admit the deviation/tolerance on this issue. 2) Diphenyl carbazide test is used to verify the presence of Hex Cr in Chromate coats over zinc. There are several other methods and different Principals specify separate tests according to their requirement. You must ask the Principal to specify an acceptable test. This is an ELV issue too.

Regards,

asif_nurie
Asif Nurie [deceased]
- New Delhi, India
With deep regret we sadly advise that Asif passed away on Jan 24, 2016
2004


The appearance of Hexavalent and Trivalent passivation is similar. Pl suggest the method to verify Trivalent passivation.

Mohan Malghan
Buyer - Bangalore, India, Karnataka
October 1, 2009




(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:

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

About/Contact  -  Privacy Policy  -  ©1995-2025 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"