Carbon fiber Profile
Carbon fiber is a fibrous carbon material, the chemical composition of the carbon content of more than 90% due to elemental carbon does not melt at high temperatures (3800K or more in sublimation), and do not dissolve in various solvents, so far can not be used elemental carbon to carbon fibers prepared as in step A which generates a pre-oxidation: heated in air, maintained at 200-300 degrees tens to hundreds of minutes to make the object of the pre-oxidized polyacrylonitrile linear molecular chain is transformed. Heat the ladder structure, so that it does not melt during carbonization temperature is maintained nonflammable carbonized fiber state B: heating in an inert atmosphere to 1200-1600 degrees, for several minutes to tens of minutes, the product can generate carbon fiber;. the inert gas used may be highly pure nitrogen, argon or helium, but more generally with high purity nitrogen graphitized C: and then in an inert atmosphere (usually high purity argon) and heated to 2000-3000 degrees, maintain a few seconds to tens of seconds; thus generated carbon fiber, also known as graphite fibers.
Carbon fibers are polyacrylonitrile fiber; pitch fiber; rayon or phenolic fibers obtained by carbonization; press state is divided into filaments; short fibers and chopped fiber; by the mechanical properties into general-purpose and high-performance general-purpose. Carbon fiber strength of 1000 MPa (MPa), modulus of about 100GPa. high-performance carbon fiber is divided into high strength (strength 2000MPa, Modulus 250GPa) and high model (modulus 300GPa above). strength greater than 4000MPa, also known as for the ultra-strong; modulus is called ultra-high model 450GPa With the development of aerospace and aviation industry, there was high strength and high elongation carbon fiber, its elongation greater than 2% the largest amount of PAN-based carbon fiber. .
Carbon fiber has an excellent fineness (fineness of notation is the number of grams of fiber length of 9000 m), generally only about 19 grams; pull up to 300KG / MM2; there are high temperature, corrosion resistance, electrical conductivity, heat transfer, Peng expansion coefficient and a series of excellent performance. There are few other materials like carbon fiber NA me as having more excellent performance.
The use of carbon fiber is mainly
1 with its light and strong and light and stiff mechanical properties; widely used in aviation; aerospace; defense; sports and leisure structural materials;
2 with its dimensional stability; applied mechanical universe; radio telescopes and various molded products;
3 advantage of its resistance to fatigue; applied to a helicopter blade; the use of its vibration damping properties; used in audio equipment;
4 advantage of its high temperature resistance; used in aircraft brakes and insulation materials; the use of its chemical resistance; applied to packing and filter;
5 using its electrical characteristics; applied to an electrode material; electromagnetic shielding materials; anti-static materials;
6 using its biocompatibility; applied artificial; ligament; using its X- ray permeability; applied to the X- ray deck, etc.