Density: The density of carbon fiber ranges from 1.5 to 2.0 g/cm³, which depends primarily on the carbonization temperature, in addition to the structure of the precursor fiber. Generally, after high-temperature (3000℃) graphitization treatment, its density can reach 2.0 g/cm³.
Coefficient of Thermal Expansion: The coefficient of thermal expansion of carbon fiber differs from other fibers, exhibiting anisotropy. It is negative parallel to the fiber direction (-0.90 x 10⁻⁶ to -0.72 x 10⁻⁶ K⁻¹), and positive perpendicular to the fiber direction (22 x 10⁻⁶ to 32 x 10⁻⁶ K⁻¹).
Specific Heat Capacity: The specific heat capacity of carbon fiber is generally 7.12 x 10⁻¹ kJ/(kg·K). Thermal conductivity decreases with increasing temperature.
Specific Resistivity: The specific resistivity of carbon fiber depends on the fiber type. At 25℃, high-modulus carbon fiber has a resistivity of 775 mΩ/cm, while high-strength carbon fiber has a resistivity of 1500 mΩ/cm. Carbon fiber has a positive electromotive force (EMF), while aluminum alloy has a negative EMF. Therefore, chemical corrosion can occur when carbon fiber composites are used in combination with aluminum alloys.
