I would need to see a reference on that Meindert. There are of course
copper embrittlement mechanisms. But I don't believe any of them work at
soldering temperatures.
The mechanism of which I am aware is simple work hardening when a flexing
section works against one rigidized by solder. Easily handled by support of
the wire. There is a 75 year history of high quality military style
connectors using solder to mate wire to connector pins. This mechanism is
routinely used in high stress situations. I know of no concerns with
embrittlement...just the need to support the wire mechanically.
Hydrogen embrittlement is generally considered to occur at temperatures much
higher than soldering.
I think you need a reference or two...
Jim Donohue
"Meindert Sprang" wrote in message
...
"Jack Erbes" wrote in message
...
Meindert Sprang wrote:
snip
Correct. It is a well known physical property of copper. It hardens
when
it
is heated.
Meindert
..
You are partly right. Heating a metal above its recrystalization
temperature
softens it. For copper, you're talking about at least 480 degrees Celcius.
When copper is heated below this temperature (soldering), the remaining
oygen in the copper can react with hydrogen (possibly released by heating
flux?) causing embittlement of the copper.
That is why reusable copper spark plug washers, head gaskets, etc., are
heated to restored their sealing qualities. They get work hardened in
use and might not seal at a specified clamping force. The sealing
qualities can be restored by annealing.
Yes, but with a soldering iron, you'll never reach that temperature,
generally
Meindert
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