Talk:Oxygen-free copper

Removed comments from article

I removed two comments from the article left by Bobahlouie (talk · contribs):

(Actually, I believe this is confusing the difference between oxygen-free and low-impurity copper. Removing oxygen does not necessarily improve conductivity. In fact, for standard ETP electrical copper, oxygen is added to oxidize impurities that would degrade conductivity and therefore improve conductivity. So, when oxygen is removed, if excellent conductivity is still desired - impurities must also be removed. In fact, most oxygen free copper is used not for conductivity improvement (or even audio cables), but for resistance to hydrogen embrittlement in high-temp applications such as welding. Removing oxygen can also change/degrade mechanical properties, such as hardness, etc. See http://www.copper.org/innovations/1997/Dec1997/wiremetallurgy.html)

The difference in resistance is quite small (about 20%) [...] (This statement is not correct - ) By definition all copper for commercial and residential wiring is known as C110. C110 is what you'll find used in Romex at home depot. C110 is also by far the most widely used in any electronic wiring application. C110, C101 and C102 have conductivity within 1% or less, not 20%. See http://www.copper.org/innovations/1997/Dec1997/wiremetallurgy.html and http://www.copper.org/resources/properties/microstructure/coppers.html).

-- intgr 08:27, 25 April 2007 (UTC)

It would be great if that could be seamlessly integrated into the article. You are welcome to remove any unreferenced information, or information supported by poor sources. For more information, you can see the verifiability policy. -- intgr 08:40, 25 April 2007 (UTC)

Thanks for cleaning up the reference!

I'm new and although I plowed through the tutorial and help stuff, I guess I got a bit bogged down (wow this is complicated!) and blundered in to it all. I'll try to update this in the future with more relevant and accurate facts and applications about OFC. :-)

Bobahlouie 02:41, 26 April 2007 (UTC)

I am a bit concerned that the article addresses the conductivity of OFC but never actually gives any details. Very unscientific.

Plaides (talk) 04:40, 19 August 2008 (UTC)

Contradiction

The intro states, with refs, that OFC has a oxygen content of less than "0.001% oxygen". However, in the "specifications" section it states that C11000 has an oxygen content of "0.02% to 0.04% (typical)." Either C11000 isn't an OFC or the intro is wrong. Someone with more knowledge needs to fix this. Wizard191 (talk) 15:02, 2 November 2010 (UTC)

Numbers don't add up

The Standards section states that "Conductivity is generally specified relative to the 1913 [IACS] of 58 MS/m. [...] (Ultra-pure copper has a conductivity of 58.65 MS/m, 102.75% IACS.)"

The numbers don't match. 58.65 MS/m are about 101.1% of 58MS/m. I don't know which number is wrong, but even if the "58" is only 57.5, 102.0% of that would already be 58.65, so there's more than just roundoff error. BTW, it appears that 58 is an exact value which was put in the standard because it was both close to the "perfect" value and feasible in practice. The source ^[5] is dead, too, so I can't check the numbers. 217.255.129.154 (talk) 10:51, 12 April 2016 (UTC)

Origin of the term "tough pitch"

Hello all you copper experts. Can anyone tell me what the term "pitch" means in the context of copper? And in particular its most common form, "tough pitch?" And what is the origin of this use of the word "pitch?" Is the meaning of "tough" as in ductile, or does this mean something else?

Thanks so much!

Yankeepapa13 (talk) 23:03, 29 August 2016 (UTC)

"Tough pitch" was a term used in Great Britain by at least the 19th century; the same concept in Germany was called hammer-gaar. The copper was refined to make it more ductile and malleable, that is, less inclined to fracture when bent or worked. Dry copper (Gaar Kupfer) was smelted until most of the metal oxides were removed, at which point it would make sheets and wire that had the highest level of ductility possible. The "tough" part of "tough pitch" implied that the copper could be hammered and bent quite a lot before fracturing. [1] If the copper was further refined to remove more oxides then the more brittle result was called "overpoled". Binksternet (talk) 00:02, 30 August 2016 (UTC)

"Pitch" is the condition of the copper during the smelting process.[2] It's the same meaning as in the common term "fever pitch" – it refers to the level or intensity of something, how far it has changed along a continuum. Binksternet (talk) 07:42, 30 August 2016 (UTC)