MATERIALS:
Since World War II, plastics have been used in military
aircraft windows as "bulletproof glass". Take this already impressive
performance record and add to it the dramatic improvements seen below
when fiber is added:
(REF. Composite Materials Handbook, M. Schwartz,
Chief of Metals Processing, Sikorsky Aircraft)
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Here is a performance map of the fibers themselves.
REF. Engineering Mechanics of Composite Materials, by
Isaac M. Daniel & Ori Ishai, Oxford University Press, 1994
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As you can see, simple E-glass, commonly known as fiberglass,
is actually superior to aluminum and steel. S-glass is used in aerospace structures,
such as the Hubble Space Telescope trusswork. Carbon and graphite are used
in high-impact applications, such as mountain bikes and tennis raquets.
REF: Sikorsky Aircraft (See Ref. 6 above)
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Here is another kind of performance map, courtesy of DuPont.
This is tensile strength and tensile modulus divided by density.
Notice once again how common E-glass outperforms both aluminum
and steel, let alone wood.
CONSTRUCTION:
One could wish for single-piece construction,
with no seams, discontinuities, or other imperfection. However, ages
of engineering for high strength tell us that many layers and special chemical
processes are required to achieve the ultimate, for example, Damascus steel,
or the hundreds of layers of the Japanese sword. Before there was metal,
ancient people made bows that could shoot an arrow almost a mile using
multiple layers of hide, horn, and other materials. This type of bow
was documented in Scientific American. The point is, composite fabrication
actually has an illustrious role in human civilization, and is has many applications where sound, vibration, and strength are the issues.