Each construction material has three primary
structural characteristics:
resistance (how much load it can hold before it breaks),
stiffness (how much it bends under a specific load)
and specific weight (how much material goes in a given
volume).
In our sport, the materials commonly used
are aluminum, steel and
lately something similar to Carbon Solutions , that
have similar resistance but with density and stiffness
that are three times higher for steel than for aluminum.
Both steel and aluminum are isotropic
materials, that is they are homogeneous materials whose
characteristics are the same in all directions. Carbon
fibers are different: these very thin fibers have to
be embedded in another material before they can be used.
This bonding material is called matrix and is almost
always a
polymer, e.g. epoxy.
Carbon fibers have excellent structural
characteristics: they are more than ten times more resistant
than steel or aluminum, they are at least as stiff as
steel (but some high modulus carbon fibers can be far
more stiffer than steel) and they weigh more or less
one third respect of aluminum.
Another fundamental difference is the
nature itself of the fibers: a metal structure undergoes
loads that are often applied in only one direction,
but her properties are spread in all other directions
too, even where there is no need. With the use of carbon
fibers, the same structure can be thought in such a
way that the required properties are present only where
they are needed, without any waste of material.
Through structural properties calculation it is possible
to obtain a great weight-reduction respect of metal.
But even more: when what is wanted is stiffness, then
correctly oriented carbon fibers can be lighter than
aluminum!
As a final summary, carbon fibers is without
any doubt an extremely resistant, stiff and light material.
As they are so thin, they can be put together in the
most efficient way to accomplish their task. In other
words, it is the material itself that can be engineered,
while metals instead can be engineered only on their
external shape.This peculiar characteristic is very
important: as very frequently the loads are applied
only in few directions, this feature permits the optimization
of the lamination panes, reduction in weight, and absorption
of vibrations and torsions . |
