What are the physical properties of carbon fiber composites?

Release time:

2024-01-23

Carbon fiber composite material is a kind of new material with good mechanical properties, which has two characteristics of strong tensile strength of carbon material and soft processability of fiber. The carbon fiber has a tensile strength of about 2 to 7GPa and a tensile modulus of about 200 to 700GPa. The density is about 1.5 to 2.0 grams per cubic centimeter, which in addition to the original silk structure, mainly depends on the temperature of the carbonization process.

General after high temperature 3000 ℃ graphitization treatment, the density of up to 2.0 grams per cubic centimeter. In addition, its weight is very light, its specific gravity is lighter than that of aluminum, less than 1/4 of steel, and its specific strength is 20 times that of iron. The thermal expansion coefficient of carbon fiber is different from other fibers, and it has anisotropic characteristics. The specific heat capacity of carbon fiber is generally 7.12. The decrease in thermal conductivity with increasing temperature is negative parallel to the fiber direction (0.72 to 0.90) and positive perpendicular to the fiber direction (32 to 22). The specific resistance of carbon fiber is related to the type of fiber. At 25°C, the high modulus is 775, and the high strength carbon fiber is 1500 per centimeter. This results in carbon fibers having the highest specific strength and specific modulus of all high performance fibers. Compared with titanium, steel, aluminum and other metal materials, carbon fiber has the characteristics of high strength, high modulus, low density and small linear expansion coefficient in physical properties.

Carbon fiber in addition to the general characteristics of carbon materials, its shape has significant anisotropy and soft, can be processed into a variety of fabrics, but also because of the small proportion, along the direction of the fiber axis shows a high strength, carbon fiber reinforced epoxy resin composite materials, its specific strength, modulus than the comprehensive index, in the existing structural materials is higher.

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