Carbon fiber refers to high strength and high modulus fiber with carbon content above 90%. High temperature resistance ranks first among all chemical fibers. Acrylic fiber and viscose fiber are used as raw materials, which are oxidized and carbonized at high temperature. Carbon fiber is not simple carbon. Mainly composed of carbon, it has the characteristics of high temperature resistance, friction resistance, heat conduction and corrosion resistance. It is fibrous and soft in appearance, and can be processed into various fabrics. Because its graphite microcrystal structure is preferentially oriented along the fiber axis, it has high strength and modulus along the fiber axis.
Carbon fiber has low density, so its specific strength and specific modulus are high. The main purpose of carbon fiber is to be used as a reinforcing material, compounded with resin, metal, ceramics and carbon to make advanced composite materials. Carbon fiber reinforced epoxy resin composites have the highest specific strength and modulus among existing engineering materials. The diameter of carbon fiber is only 5 microns, which is equivalent to one tenth to one twelfth of a hair, but its strength is more than four times that of aluminum alloy.
Development course of carbon fiber
1879, Edison used cellulose fibers, such as bamboo, flax or cotton yarn, to make carbon fibers for the first time and obtained a patent. However, the mechanical properties of the fiber made at that time were very low, and the process could not be industrialized, which failed to achieve development.
In the early 1950s, due to the development of advanced technologies such as rocket, aerospace and aviation, new materials with high specific strength, high specific modulus and high temperature resistance were urgently needed. In addition, the precursor can be made into carbon fiber continuous filament after heat treatment, which lays the foundation for carbon fiber industrialization.
In the early 1990s, high-performance and ultra-high-performance carbon fibers appeared. It is expected that the future work will focus on improving technology, expanding production, reducing costs and developing applications.
The above contents refer to Baidu Encyclopedia-Carbon Fiber.