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The “carbon fiber” name does not originate from actual carbon ‐ the natural
carbon is better known as diamond ‐ but from one of its early production stages.
The "carbon" part of today's fiber is actually a derivative of oil, polyacrylonitrile.
Polyacrylonitrile is first transformed in a wire and then put in an oven in order
to be "carbonized" at temperatures ranging from 2800 and 3000 degrees celsius.
At that point, the wire is woven, soaked with epoxy resin and stored at ‐30
degrees celsius to prevent catalysis, which would make the resin tougher and
the whole production process much more difficult. In automotive engineering,
in order to produce high‐quality products, the fibers used vary from 200 to 800
grams per square meter with different types of fabric, from the plain one (which
seems made of little squares and is used for cosmetic purposes), to the twill
(fishbone) and uni‐directional (all the fibers are in the same direction) types.
After deciding what kind of component needs to be built, a mold is designed
and, depending on the characteristics needed, several layers of fiber are laid in
it. The mold is put in a vacuum container and then in an autoclave, which in
substance is a pressurized oven that generates a pressure varying from 2 to 6
kilos per square centimeter and a temperature of 100‐150° C for 80 to 120
minutes. Once out of its mold, the component is ready. The key features to
assess a quality carbon fiber component are the consistency and uniformity of
the texture, the absence of air bubbles and the look of the component's internal
side: te carbon fiber must be visible to avoid dealing with pieces that have just
fiberglass on the inside but just painted in black.
W
HAT
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CARBON
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