What is carbon fiber? What is it used for?

Carbon fiber is a new fiber material with high strength and high modulus, and its carbon content is as high as 95%. It is a microcrystalline graphite material made of organic fibers such as flaky graphite microcrystals piled up along the fiber axis and carbonized and graphitized. Carbon fiber is "soft outside and rigid inside", which is lighter than aluminum, but stronger than steel, and has the characteristics of corrosion resistance and high modulus. It is an important material for national defense, military industry and civil use. It not only has the inherent characteristics of carbon materials, but also has the softness and machinability of textile fibers, and is a new generation of reinforced fibers. \x0d\ carbon fiber has many excellent properties, such as high axial strength and modulus, low density, high specific performance, no creep, ultra-high temperature resistance in non-oxidizing environment, good fatigue resistance, specific heat and conductivity between nonmetal and metal, small thermal expansion coefficient and anisotropy, good corrosion resistance and good X-ray permeability. Good electrical and thermal conductivity, good electromagnetic shielding, etc. \x0d\ Compared with traditional glass fiber, the Young's modulus of carbon fiber is more than three times; Compared with Kevlar fiber, its Young's modulus is about twice that of Kevlar fiber. It is insoluble and swollen in organic solvents, acids and alkalis, and has outstanding corrosion resistance. \x0d\x0d\ Application field \ x0d \ Carbon fiber is an important strategic material for national defense, military industry and national economic development, and it is a key technology-intensive material. With the academic research from short fiber carbon fiber to long fiber carbon fiber, the technology and products of making heating materials from carbon fiber are gradually popularized. Under the background of high-speed industrialization in the world today, the uses of carbon fiber are becoming diversified. In China, long fiber has been used as a kind of high-performance fiber, and carbon fiber composites have irreplaceable advantages when high temperature and high physical stability are required. The higher the specific strength of the material, the smaller the weight of the component, the higher the specific modulus and the greater the stiffness of the component. It is precisely because of its excellent performance that carbon fiber has broad application prospects in national defense and civil fields. \x0d\ carbon fiber carbon materials have been widely used in various fields of military and civilian industries. From aerospace, aviation, automobile, electronics, machinery, chemical industry, textile and other civil industries to sports equipment and leisure products. Carbon fiber reinforced composites can be used in military fields such as aircraft manufacturing, industrial fields such as wind power blades, electromagnetic shielding materials, artificial ligaments and other human body replacement materials, as well as manufacturing rocket shells, motorboats, industrial robots, automobile leaf springs, transmission shafts and so on. Bats and other sports fields. Carbon fiber is a typical new industrial material in high-tech field. \x0d\x0d\ composite material \ x0d \ carbon fiber is not only used as thermal insulation material in traditional use. Most of them are used as reinforcing materials and added to materials such as resin, metal, ceramics and concrete to form composite materials. Carbon fiber has become the most important reinforcement of advanced composites. Carbon fiber composites have the characteristics of light and strong, light and rigid, high temperature resistance, corrosion resistance, fatigue resistance, good structural and dimensional stability, good design, and can be integrally molded in a large area, and are widely used in aerospace, national defense and military industry, civil industry and other fields. Carbon fiber can be processed into fabric, felt, mat, belt, paper and other materials. High-performance carbon fiber is the most important reinforcing material for manufacturing advanced composites. \x0d\x0d\ civil architecture \ x0d \ civil architecture field: carbon fiber is also used to strengthen industrial and civil buildings, railway and highway bridges, tunnels, chimneys, tower structures, etc. In railway construction, large roof systems and sound insulation walls will have good applications in the future, and these will also be promising applications of carbon fiber. It has the characteristics of low density, high strength, good durability, strong corrosion resistance, acid and alkali resistance, good flexibility and strong strain capacity. The truss frame roof made of carbon fiber pipe is about 50% lighter than steel, which makes the large structure reach the practical level and greatly improves the construction efficiency and seismic performance. In addition, when the concrete structure is strengthened with carbon fiber, there is no need to add bolts and rivets to fix it, which has little disturbance to the original concrete structure and simple construction technology. \x0d\x0d\ aerospace \ x0d \ carbon fiber is an essential strategic basic material for advanced weapons and equipment such as rockets, satellites, missiles, fighters and ships. The application of carbon fiber composite materials in strategic missile body and engine shell can greatly reduce the weight and improve the missile's range and assault capability. For example, the third-stage shell of intercontinental missiles developed by the United States in the 1980s is made of carbon fiber and epoxy resin composites. Carbon fiber composites are also widely used in new generation fighters. For example, the fourth generation fighter F22 in the United States uses about 24% carbon fiber composite materials, which makes the fighter have the characteristics of hypersonic cruise, over-the-horizon combat, high maneuverability and stealth. Boeing launched a new generation of sonic cruisers, equipped with high-speed wide-body passenger aircraft. About 60% of the structural components will be made of reinforced carbon fiber plastic composites, including wings. The performance of carbon fiber composite brake preform developed in China has reached the international level. Domestic carbon and carbon brake discs manufactured by this prefabrication technology have been equipped in batches on military aircraft of national defense key models, and have been used on B757 civil aircraft, and their use in other aircraft is also being tested, and will be extended to tanks, high-speed trains, luxury cars, racing cars and so on. Carbon fiber is lighter than aluminum, but its strength is similar. Carbon fiber also has important application value in ships, which can reduce the structural weight of ships and increase the effective load of ships, thus improving the ability to transport combat materials. Carbon fiber has no problems of corrosion and rust. Because the use of carbon fiber material can greatly reduce the structural weight, it can significantly improve fuel efficiency. Planes and spacecrafts such as satellites and rockets made of carbon fiber and plastic composite materials can save a lot of fuel because of their small mass, low noise and low power consumption. It is reported that every time the mass of the space shuttle is reduced by 1 kg, the launch vehicle can be reduced by 500 kg. \x0d\ carbon fiber is also an excellent material to make modern vehicles such as large civil aircraft, automobiles and high-speed trains "lightweight". The demand for carbon fiber in aviation applications is increasing. About 50% carbon fiber composite materials are used in the new generation of large-scale civil airliners Airbus A380 and Boeing 787. Boeing 777 aircraft uses carbon fiber as structural material, including horizontal and vertical transverse tail and beam, which is called important structural material, so its quality requirements are extremely demanding. The fuselage of Boeing 787 is also made of carbon fiber, which makes the plane fly faster and consume less fuel, and at the same time increases the humidity of the cabin and makes passengers more comfortable. Airbus also uses a lot of carbon fiber on their planes, and carbon fiber will be widely used in the new passenger plane A380. This reduces the weight of the aircraft fuselage structure by 20%, saving 20% fuel compared with similar aircraft, thus greatly reducing operating costs and reducing carbon dioxide emissions. \x0d\ x0d \ automobile material \ x0d \ carbon fiber material has also become the favorite material of automobile manufacturers, and \ x0d \ x0d \ has been widely used in automobile interior and exterior decoration. As an automobile material, the biggest advantage of carbon fiber is its light weight and high strength, only 20% to 30% of that of steel, but its hardness is more than 10 times that of steel. Therefore, the use of carbon fiber materials in automobile manufacturing can make the automobile lightweight, make a breakthrough, and bring social benefits of energy saving. The industry believes that the use of carbon fiber in automobile manufacturing will increase. \x0d\ A carbon fiber car developed by Chinese Academy of Sciences is mainly on the outer shell: on the hood of a car made of ordinary materials, the paint surface is likely to sag when struck hard with a hammer, but the car shell of this car is very strong, and it will rebound quickly after hitting the hood hard, and the surface is not damaged at all. Researchers say that cars made of carbon fiber composite materials are lighter and faster than cars made of ordinary steel. The carbon fiber car abandons the traditional steel structure and is made of a large number of carbon fiber materials, which can reduce the weight of the car by 60% compared with ordinary steel. With the same fuel consumption, this car can drive 50 kilometers more per hour. \x0d\ Carbon fiber is light, but it is safe. Although it looks like plastic, in fact, this material has stronger impact resistance than steel, especially the steering wheel made of carbon fiber, which has higher mechanical strength and impact resistance. With the cooperation of composite materials, carbon fiber vehicles have become armored vehicles in family cars. This carbon fiber material has been applied to the skirts of high-speed trains. \x0d\x0d\ fiber reinforcement \ x0d \ carbon fiber reinforcement includes carbon fiber cloth reinforcement and carbon fiber plate reinforcement. The United States, Japan and other developed countries began to study the application of carbon fiber materials in the reinforcement and repair of concrete structures in the 1980s. This technology started very late in China, but with the rapid development of China's economic construction and transportation, a considerable number of existing buildings have problems left over from history because of the low design load standard at that time, and some buildings are difficult to meet the requirements of the current standards because of the change of their use functions, so they are in urgent need of maintenance and reinforcement. There are many commonly used reinforcement methods, such as enlarging cross section, steel-clad reinforcement, steel-bonded reinforcement, carbon fiber reinforcement and so on. Strengthening and repairing structures with carbon fiber is another new structural strengthening technology after increasing the concrete section and sticking steel. \x0d\ From 1997, China began to introduce carbon fiber composite materials from abroad to strengthen concrete structures. It has become a hot spot in research and engineering application. Dozens of universities and research institutes in China have carried out this research work and achieved a number of research results close to the international advanced level. As China has the largest civil building market in the world, the application of carbon fiber reinforced building structures will show an increasing trend. \x0d\x0d\ sporting goods \ x0d \ carbon fiber is used in the field of sports and leisure. Sports goods such as clubs, fishing rods, tennis rackets, badminton rackets, bicycles, ski poles, snowboards, windsurfing masts and sailboat hulls are the main users of carbon fiber. Carbon fiber can be used for daily necessities, such as home appliances such as stereos, yuba and heaters, and also for electronic products such as mobile phones and notebook computers. \x0d\ Three important sports applications are bat and racket frame. It is estimated that the annual output of bats is 34 million. 40% carbon fiber bats in the world are made of carbon fiber. The output of carbon fiber fishing rods in the world is about 20 million pairs per year. The market capacity of tennis racket frames is about 6 million pairs per year, and other sports applications include ice hockey sticks and ski poles. Carbon fiber is also used in boating, rowing and other marine sports.