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Chromium in Stainless Steel 304

Hi

Could someone tell me if the Chromium content in Stainless Steel 304 is in anyway a Hexavelent chromium?

Kannan Munukur
Datafield India Private Limited - Coimbatore, TN, India
2005

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First of two simultaneous responses --

Absolutely zero IF it has NOT received a chromic acid passivation. The chrome has a valence of zero in the metallic state.

James Watts
- Navarre, Florida
2005

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Second of two simultaneous responses --

It is not in any way at all hexavalent chrome.

It is in insoluble metallic form, with oxidation number 0 (zero), not in soluble salt form with oxidation number 3 or 6.

Bill Reynolds [deceased]
consultant metallurgist - Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.
2005

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Hexavalent chromium refers to chromium when it is the form of a compound; normally this will be as "chromate", "dichromate" or "bichromate" and it refers to the oxidation state, or valence, of the chromium when it is 6. Stainless steels are composed of chromium alloys where metallic chromium is mixed with iron and other elements, so the chromium here remains as a metal and has an oxidation state of 0 (zero). The only way that stainless steel may be considered as having hexavalent chromium is IF it has been treated with a hexavalent chromium solution for, say, a conversion coating. For some reason, and I have no idea why, legislators like putting the fear of God into people when they are drafting technologically based legislation. Unfortunately a high level of the population have no idea what the legislators are talking about as they (the general public) have very little scientific understanding. It should be the job of legislators to make the laws understandable by the general public and not to start scaremongering. Perhaps the education systems around the world should make science as important as basic reading and writing - it is surely just as important. However, if they did, then perhaps the populations around the world would begin to see how incompetent and scientifically inept many legislators and politicians are!

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2005

Ed. note: "The whole aim of practical politics is to keep the populace alarmed (and hence clamorous to be led to safety) by menacing it with an endless series of hobgoblins, all of them imaginary." -H. L. Mencken

Yes hexavalent or trivalent chromium they could be interchanged in the presence of anaerobic bacteria and the presence of redox oxidation in systems (soil

Bhuvana Balasubramanian
- New Jersey
January 14, 2008