wrote in message
ups.com...
On Oct 26, 11:07 am, "Adam Corolla"
wrote:
wrote in message


Would tungsten be melted if there was a way to make an effective crucible
that wouldn't melt or react with the tungsten?- Hide quoted text -

- Show quoted text -

Tungsten does melt. You have correctly discerned that the issue
becomes containing it. Molds of carbon which may be water-cooled and/
or plasma sprayed with a tungsten coating are used in the arc casting
process. There are other methods as well which utilize water cooled
tubes where powder forms thin layer which is continually melted by an
arc or an electron beam. Powder is continually added and the
solidified cylinder which is created moves downward out of the tube as
each new layer is melted. Thus only a small amount of material is
melted at any one time. You will generally not ever see large
quantities of molten tungsten in a big crucible, such as those found
in a steel refinery.


Why don't they just use a tantalum hafnium carbide crucible? Is that stuff
too expensive? If not, it should work--it's melting point is over 1400
degrees F. higher than Tungsten's. Or for that matter, they could use a
carbon crucible. Carbon remains solid at temperatures considerably higher
than tungsten. Maybe they can't be used as crucibles for tungsten because
those materials would react with the molten tungsten?