[potatoe94]

is it that serious ? As normal bending such as wrapping them around your hand and storing them does not strain the copper in the cables ... if so i think my Headphones are all lousy now :s

 

[jcx]

Quote:

Cold working copper to 1% strain reduces conductivity by a factor of 100.

"not intended to be factual"?

 

[Steve Eddy]

Quote:

HA!
 
Love it!
 
se
 
 
 

 

[cegras]

 
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Quote:

You aren't really plastically deforming the Cu unless you bend the cable quite a bit. Therefore you aren't creating any dislocations.
 
Considering you are using drawn wire, there are already a massive amount of dislocations present, not to mention the low stacking fault energy of Cu, which gives it a huge propensity for twinning. 

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Standard practice is to take a 0.1% offset as the plastic instability, although plastic deformation usually occurs before that.
 
http://en.wikipedia.org/wiki/Yield_(engineering)
 
Quote:

And I'm not sure where you are getting that info, but between coarse grained Cu and nanocrystalline Cu there is about an order of magnitude difference in the conductivity, not 2.
 
Just look at this paper about differences in conductivity due to twinning in nanocrystalline Cu
 
http://www.synl.ac.cn/org/mat/llu/PDF/japchen201006010686.pdf

Hibbard et al, 1958. Strain is different from grain size.
 
Grain size has a much smaller effect though .. only 2-3 times versus 1/d.