On Fri, 19 Mar 2010 18:02:05 -0700, Archimedes' Lever
wrote:

On Fri, 19 Mar 2010 15:01:19 -0700, John Larkin
wrote:

The work hardening probably has less effect on the resistance
than the elongation;


Elongation IS where the work hardening occurs. D'oh!

The change of resistance from elongation is purely geometrical; the
wire gets longer and its cross-sectional area/diameter correspondingly
drops, and the area reduction increases its per-unit-length
resistance. There will be additional resistance increase from messing
with the crystal structure. Two things are going on here. You could
anneal out the crystal thing but not the elongation.


Copper... if you move it, it will harden.

Unless you move it *very* slowly.

How slowly would I have to stretch it to avoid work hardening?

John