solid copper wire get stiff when old ?

[Stevenfyeager]

Had some 50 year old #6 solid copper wire given to me, but I can hardly bend it. It looks solid copper when cut but compared to newer wire it is almost impossible to bend. There wasn't a copper-steel alloy made was there ?

 

[hbiss]

Are you sure it's electrical wire? Does it have insulation with markings? No such thing as copper-steel alloy. Maybe hard annealed for line work?

-Hal

 

[Buck Parrish]

I too have came across it being used as a ground wire some where in central western Indiana. I don't know what it was.

 

[tom baker]

I have noted copper wire gets harder as it ages. It maybe your ground wire is annealed differently,

 

[Buck Parrish]

Yep could have been annealed differently during manufacturing,

We some times keep a can of water near by to dip our drill bits in to keep them from tempering.

 

[retirede]

Old overhead phone wire used to be copper plated steel. It was almost unbendable.

 

[Stevenfyeager]

Southern Indiana. It sure looks copper all the way through, but feels like trying to bend steel. I compared to modern solid copper wire and no comparison.

 

[don_resqcapt19]

You can get hard drawn copper conductors and it is very stiff as compared to normal copper conductors.

 

[retirede]

Southern Indiana. It sure looks copper all the way through, but feels like trying to bend steel. I compared to modern solid copper wire and no comparison.

If it’s copper plated steel, you can’t cut it with a pair of dykes. In fact, it will likely damage them.

 

[kwired]

"Hard drawn" copper was used for overhead lines at one time. Still can find some still in use here and there at times. Stopped seeing new installs with it 50-60 maybe even 70 years ago.

 

[gar]

210830-1136 EDT

In general ---

Materials work harden. If you take a piece of copper and pound on it, then it will become harder and more brittle. If you now adequately heat and somewhat slowly cool it, then you will soften the piece, and you can go back and continue reshaping the piece. To make a small diameter wire this process will need to be repeated many times.

There are considerable differences in how ferrous and non-ferrous materials behave. Ferrous materials below a certain stress level have infinite fatigue life. Not so of non-ferrous materials.

Age hardening occurs for some materials. Copper wire strung between power poles will work harden from temperature cycling. and wind moving the wire around.

To determine if a wire is solid copper, or an alloy, vs copper clad steel use an abrasive saw to cut thru the wire, then inspect wire color as you scan across the cross section.

See https://terrylove.com/forums/index.php?threads/does-soft-rolled-copper-get-harder-over-time.48030/ for an interesting discussion.

.

 

[hbiss]

I have noticed that copper conductors that have been moved around and flexed like when replacing receptacles and switches get work hardened. I have a habit of trying to dress my conductors in boxes so that they look neat but after bending them around for awhile I can never seem to get them to look the same as when first installed.

-Hal

 

[don_resqcapt19]

"Hard drawn" copper was used for overhead lines at one time. Still can find some still in use here and there at times. Stopped seeing new installs with it 50-60 maybe even 70 years ago.

it was specified for under ground grounding rings and jumpers for some of my industrial jobs in the 80s and 90s

 

[Stevenfyeager]

So if it looks like copper, how do I recycle it ?

 

[romex jockey]

solid copper wire get stiff when old ?​

>>>>

​

~R J~

 

[DrSparks]

Had some 50 year old #6 solid copper wire given to me, but I can hardly bend it. It looks solid copper when cut but compared to newer wire it is almost impossible to bend. There wasn't a copper-steel alloy made was there ?

Probably the insulation that's stiff. They used to use a thermoset plastic that hardened over time.

Sent from my BE2028 using Tapatalk

 

[brantmacga]

If only everything worked this way, a whole pharmaceutical market would be wiped out


Sent from my iPhone using Tapatalk

 

[Jraef]

Hard drawn copper is all copper, it’s just in a more “raw” form. The wire we are used to using is “annealed” meaning they take hard drawn copper and work it with heat to make it softer and less stiff. The exchange is that annealed copper wire has 97% of the conductivity of hard drawn copper, but almost half the tensile strength, which relates to its ability to flex and bend. People that make copper wire sculptures use hard drawn copper (when they can get it) because it’s less susceptible to the form getting altered by something bumping into it (a friend was an artist who made copper wire sculptures).

Annealed copper wire does not stiffen with age. So most likely what you have encountered is someone having used hard drawn copper wire for something, I’d guess because they had it at hand that day. Other than the stiffness (and slightly higher cost because of lower demand), there is no reason it can’t be used.

If you suspect copper clad steel, touch it with a magnet. Copper is not magnetic but if there is a steel core, it will be attracted to the magnet right through the copper cladding.

 

[domnic]

Hard drawn copper is all copper, it’s just in a more “raw” form. The wire we are used to using is “annealed” meaning they take hard drawn copper and work it with heat to make it softer and less stiff. The exchange is that annealed copper wire has 97% of the conductivity of hard drawn copper, but almost half the tensile strength, which relates to its ability to flex and bend. People that make copper wire sculptures use hard drawn copper (when they can get it) because it’s less susceptible to the form getting altered by something bumping into it (a friend was an artist who made copper wire sculptures).

Annealed copper wire does not stiffen with age. So most likely what you have encountered is someone having used hard drawn copper wire for something, I’d guess because they had it at hand that day. Other than the stiffness (and slightly higher cost because of lower demand), there is no reason it can’t be used.

If you suspect copper clad steel, touch it with a magnet. Copper is not magnetic but if there is a steel core, it will be attracted to the magnet right through the copper cladding.

Annealed copper wire has 97% of hard drawn wire. not true.

 

[kwired]

So if it looks like copper, how do I recycle it ?

If the scrap yard holds a magnet to it and it sticks, you will get steel pricing instead of copper pricing.