The material. Carbon fiber reinforced composites (CFRPs) offer greater stiffness and strength than any other type, but they are considerably more expensive than GFRP (see record). Continuous fibers in a polyester or epoxy matrix give the highest performance. The fibers carry the mechanical loads, whereas the matrix material transmits loads to the fibers and provides ductility and toughness as well as protecting the fibers from damage caused by handling or the environment. It is the matrix material that limits the service temperature and processing conditions.
Composition
Epoxy + continuous HS carbon fiber reinforcement (0, н— 45, 90), quasiisotropic layup.
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General properties |
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Density |
1500 – |
1600 |
kg/m3 |
|
Price |
*40.0 – |
44.0 |
USD/kg |
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Mechanical properties |
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Young’s modulus |
69 – |
150 |
GPa |
|
Yield strength (elastic limit) |
550 – |
1050 |
MPa |
|
Tensile strength |
550 – |
1050 |
MPa |
|
Elongation |
*0.32 – |
0.35 |
% |
|
Hardness—Vickers |
*10.8 – |
21.5 |
HV |
|
Fatigue strength at 107 cycles |
*150 – |
300 |
MPa |
|
Fracture toughness |
*6.12 – |
20 |
MPa. m1/2 |
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Thermal properties |
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Maximum service temperature |
*140 – |
220 |
°C |
|
Thermal conductor or insulator? Thermal conductivity |
Poor insulator *1.28 – |
2.6 |
W/m. K |
|
Specific heat capacity |
*902 – |
1037 |
J/kg. K |
|
Thermal expansion coefficient |
*1 – |
4 |
p, strain/°C |
|
Electrical properties Electrical conductor or insulator? Electrical resistivity |
Poor conductor *1.65 X 105 – |
9.46 X 105 |
pnhm. cm |
A CFRP bike frame. (Courtesy TREK.)
Typical uses. Lightweight structural members in aerospace, ground transport, and sports equipment such as bikes, golf clubs, oars, boats, and racquets; springs; pressure vessels.
