Carbon fiber is a specialized type of fiber composed primarily of carbon elements; its carbon content varies depending on the specific type, generally exceeding 90%. Carbon fiber possesses the characteristic properties of typical carbon-based materials-such as high-temperature resistance, abrasion resistance, electrical conductivity, thermal conductivity, and corrosion resistance. However, unlike ordinary carbon materials, it exhibits distinct anisotropy in its physical form; it is flexible, can be processed into various fabric structures, and demonstrates exceptionally high tensile strength along the direction of the fiber axis. Furthermore, carbon fiber has a low specific gravity, resulting in a remarkably high specific strength.
Carbon fiber is manufactured from synthetic chemical fibers that possess a high carbon content and do not melt during thermal processing. These precursor fibers undergo a series of manufacturing processes, including thermal stabilization (oxidation), carbonization, and graphitization.
Carbon fiber is a novel material distinguished by its superior mechanical properties. Its specific gravity is less than one-quarter that of steel.
Carbon fiber-reinforced polymer (CFRP) composites typically exhibit a tensile strength exceeding 3500 MPa-seven to nine times that of steel-and a tensile elastic modulus ranging from 23,000 to 43,000 MPa, which is also higher than that of steel. Consequently, the specific strength of CFRP-defined as the ratio of a material's strength to its density-can exceed 2000 MPa/(g/cm³), whereas the specific strength of A3 steel is merely around 59 MPa/(g/cm³); similarly, its specific modulus is also higher than that of steel.
