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Carbon fibers today
All
commercial carbon fibers produced today are based on rayon, PAN, or pitch.
Rayon-based fibers were the first in commercial production in 1959, and
they led the way to the earliest applications, which were primarily military.
PAN-based fibers have replaced rayon-based fibers in most applications,
because they are superior in several respects, notably in tensile strength.
Fibers from PAN fueled the explosive growth of the carbon fiber industry
since 1970, and they are now used in a wide array of applications such
as aircraft brakes, space structures, military and commercial planes,
lithium batteries, sporting goods, and structural reinforcement in construction
materials. In the late 1970s, Union Carbide formed a separate division
as its primary carbon fiber producer; the business has since been sold
to Amoco and then to Cytec, which is among a group of major carbon fiber
manufacturers that spans the globe.
Pitch-based fibers are unique in their ability to achieve ultrahigh Young’s
modulus and thermal conductivity and, therefore, have found an assured
place in critical military and space applications. But their high cost
has kept production to a minimum; only a few Japanese companies in addition
to Cytec are currently making commercial mesophase fibers. A lower modulus,
non-graphitized mesophase-pitch-based fiber, which is much lower in cost,
is used extensively for aircraft brakes. Conoco recently announced plans
to start a plant predicated on making large quantities of mesophase fibers
at very low cost, with potential for going into applications like construction,
cement reinforcement, and others where large volumes and low prices would
be necessary. But Conoco chose not to go forward with the project because
of technical problems and market issues.
The cost of making carbon fibers has been reduced drastically in the last
20 years, and researchers are bringing that cost down every day. As they
do, many of the applications once considered impossible will become reality.
Carbon fibers are used sparingly in automotive applications, but someday
entire body panels may be made from them. All high speed aircraft have
carbon fiber composites in their brakes and other critical parts, and
in many aircraft they are — used as the primary structures and skins
for entire planes. Carbon fibers could even be used to develop earthquake-proof
buildings and bridges.
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In May 2002, UCAR Carbon changed its name to GrafTech International. The
Parma Technical Center, now a part of GrafTech, is currently in use as
the Corporate Research and Development Laboratory.
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