On Jan 20, 2005, at 7:37 AM, Falcon Wireless Tech Support - KF4HAZ 
wrote:

> Magnesium ribbon will ignite very easily (an electric current or a 
> match).

For certain definitions of "easily."  As I recall, it's quite a pain to 
get
Mg ribbon to ignite with a match.  You can usually do it with one 
match, for
the thinner ribbon, but it's not like lighting a piece of paper.

> Fe2O3+Mg -> Mg2O3+Fe with much thermal energy released,
> this is commonly known as cad-weld.
>
Thermite.  Except that Aluminum is the traditional reducing agent, and I
thought "cad-weld" contained a fair percentage of copper oxide for 
copper's
electrical characteristics.

In general, the metal-oxide/reactive metal reactions are known as 
"Goldschmidt
reactions."  At one time these were standard mechanisms for extracting 
certain
metals from their ores.  If you're going to do something "mild" like 
weld with
such a mixture, you have to be pretty careful WRT particle sizes and 
such.  A
mixture of copper oxide and magnesium POWDERS is more apt to EXPLODE 
into a
cloud of copper vapor than produce a useful stream of liquid copper.

BillW
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