37
2
form. A wing and rudder assembly made out of composites is
shown in . Fig. 2.9. Sports boats, bicycles, tennis
11. Dimensional Stability—Composites retain their shape and size
in any environment, such as cold, hot, arid, and humid.
Natural fibre-reinforced composites, on the other hand, may
swell and shrink as the humidity changes. Composites are the
choicest of materials that have high dimensional accuracy. The
excellent dimensional accuracy of composites is attributed to
their low linear thermal expansion, nonconducting characteristics, and high rigidity.
12. Nonconductive Characteristic—Composites are nonconductive
due to the very nature of their constituent phases that include
nonconductive polymers and fibres. Only carbon or graphite
fibres conduct electricity. The nonconductivity of composites
makes them suitable for use as electric poles and for electronic
circuit boards. If electrical conductivity is needed, composites
may be designed to be electrically conductive by reinforcing
conductive materials and metal powders, such as silver
powder. The housing of conductive composites is used in
electromagnetic inductance (EMI) and electromagnetic
conductance (EMC) for the shielding of electronic circuits.
13. Nonmagnetic Characteristics—Composites are nonmagnetic as
they do not contain any magnetic material or metallic
substance. This is a unique property of composites and allows
them to be used in both electronics and electrical designs. The
nonmagnetic character of composites makes them very good
materials for constructing the hulls of stealth frigates and
boats.
Point to Ponder…
The magnetic signature of
ferromagnetic material in the
sea can be detected very easily
because there is no magnetic
material present in the sea except
in boats, ships, and submarines.
. Fig. 2.9 a Wing assembly and b rudder assembly [28] racquets, etc. are made from carbon or glass fibre-reinforced
composites because these materials easily can be moulded into complex shapes. The surface of composites also can be
moulded into any texture—from coarse to smooth
2.1 · Advantages of Polymeric Composites
2
form. A wing and rudder assembly made out of composites is
shown in . Fig. 2.9. Sports boats, bicycles, tennis
11. Dimensional Stability—Composites retain their shape and size
in any environment, such as cold, hot, arid, and humid.
Natural fibre-reinforced composites, on the other hand, may
swell and shrink as the humidity changes. Composites are the
choicest of materials that have high dimensional accuracy. The
excellent dimensional accuracy of composites is attributed to
their low linear thermal expansion, nonconducting characteristics, and high rigidity.
12. Nonconductive Characteristic—Composites are nonconductive
due to the very nature of their constituent phases that include
nonconductive polymers and fibres. Only carbon or graphite
fibres conduct electricity. The nonconductivity of composites
makes them suitable for use as electric poles and for electronic
circuit boards. If electrical conductivity is needed, composites
may be designed to be electrically conductive by reinforcing
conductive materials and metal powders, such as silver
powder. The housing of conductive composites is used in
electromagnetic inductance (EMI) and electromagnetic
conductance (EMC) for the shielding of electronic circuits.
13. Nonmagnetic Characteristics—Composites are nonmagnetic as
they do not contain any magnetic material or metallic
substance. This is a unique property of composites and allows
them to be used in both electronics and electrical designs. The
nonmagnetic character of composites makes them very good
materials for constructing the hulls of stealth frigates and
boats.
Point to Ponder…
The magnetic signature of
ferromagnetic material in the
sea can be detected very easily
because there is no magnetic
material present in the sea except
in boats, ships, and submarines.
. Fig. 2.9 a Wing assembly and b rudder assembly [28] racquets, etc. are made from carbon or glass fibre-reinforced
composites because these materials easily can be moulded into complex shapes. The surface of composites also can be
moulded into any texture—from coarse to smooth
2.1 · Advantages of Polymeric Composites