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John Passaneau · November 15th 07, 03:44 PM posted to rec.radio.amateur.antenna

art wrote in news:09534116-d261-4f5d-aeea-
:

No !!!!!!!!!
Every thing is known.
It must be in the books of Kraus and you know who.
I keep reading that the theories of radiation is well known
and widely accepted, so what is widely accepted in this area?
Is the "rust" of aluminum called bauxite by any chance?
And is it diamagnetic?
Art

Christopher Cox wrote:
Sputtering?

BTW, lots of luck with that subject, it would seem there is little
understanding on the field of study other than it works.

The "rust" on aluminum is aluminum oxide. More related to Corundum
{Al2O3}, sorry can't do subscripts in thunderbird, than Bauxite which is
{Al2O3.2H2O}. The oxide coating forms almost instantly on aluminum when
exposed to air. It is very thin and can be scratched off and will not
form if air is keep away from it which is why clamping works. The oxide
coating is also why soldering to aluminum is hard to do. If soldered in
an atmosphere without oxygen aluminum would solder easily. When aluminum
is exposed to water a white powdery coating forms. That is closer to
Bauxite as it’s a hydrated aluminum oxide of which Bauxite is just one.
Anodizing is process that makes the aluminum oxide coating thicker and
more porous so that dye can be forced into it so it can be colored. And
anodizing also is a good insulator which is why it must be scraped off
where you want to make an electrical connection.

John Passaneau
Penn State University