Jan 2004 09:58:27 -0500
Traditionally, we've used thin sheets of stainless steel to provide temporary
protection from fire. The operative word here is temporary. A metal sheet,
even one 0.060' thick, is not much of a heat sink and, while it may not burn,
sooner or later it will conduct heat to things that will: the engine bulkhead,
the
main spar and the people beyond.
This concern for the limitations of stainless steel and the low ignition temps
of room-cured resins may be coming to an end.
I just saw some specs of a new composite sandwich material made by
Touchstone Research Laboratories in Tridelphia, West Virginia. They are
targeting this as core material for use as energy absorbing medium in
automobiles. The smart money, however, sees the primary market as aircraft,
marine and container industry, all of which have storage cells of volatile fuel
and. where efficient fire resistant structural materials are scarce. There's
hope that
as volume production is achieved, the price will come down even more and the
material might be adopted for use in constructing homes.
It's light but strong stuff: one square inch of the material is said to be able
to
support the weight of a car without crushing. The density can be varied from
5 to 40 pounds per cubic foot, and while tensile strengths may not be up to
those of the graphites, they appear to be very competitive with the more
conventional materials we use in crafting home-builts.
The big thing with this material is that you can't, at any density, get it to
burn,
even with an acetylene torch! It absorbes enormous quantities of heat in spite
of its low thermal; expansion properties.
It's called CFOAM and, believe it or not, the stuff is made from coal!
They have a web site:
www.trl.com/
I've ordered a more comprehensive spec sheet and, with any luck, will soon
be able to test a sample myself.
Art Bianconi
N-67EB
