Eric Stevens wrote in message ...
On Fri, 2 Jul 2004 18:09:16 -0500, "Paul K. Dickman"
wrote:

In order to illustrate the nature of the porosity in melted copper I put a
few
pictures up.

http://tinyurl.com/3cw7p

The first labeled Casting is a small ingot cast of ca110 copper It started
out
.........
parking lot.

The size of this is indicative of how much gas was dissolved in the metal.
It is
approximately 10% of the original volume of the ingot.




Measured at what temperature and pressure?



Eyeballed mostly.
Once the outside of the ingot has chilled an ingot this small shrinks pretty
minimally. The cocks comb consists entirely of metal and gas that used to be
inside the ingot but was expelled by the gas inside the ingot.
The cocks comb is roughly 10% of the size of the ingot minus the cocks comb.

Paul K. Dickman