Carbon fiber is called "polypropylene acrylic carbon fiber" by the carbon fiber and the relevant matrix resin (such as epoxy resin) to prepare the composite material with a number of physical and mechanical properties comparable to metal. Because of its unique high temperature resistance (>3000 ℃), ablation resistance, small coefficient of thermal expansion, and high specific strength, high specific touch volume and other characteristics, widely used in aerospace, aviation, chemical, electronics and sports equipment and other fields.
Carbon fiber is also known as carbon fiber (Carbon Fiber, CF for short). In the international are known as "black gold", it following the stone and steel and other metals, is internationally known as "third-generation materials", because the composite material made of carbon fiber has a very high strength, and ultra-light, high temperature and high pressure resistance.
Carbon fiber is mainly composed of carbon, a special fiber, its carbon content varies with the type, generally more than 90%. Carbon fiber has the characteristics of general carbon materials, such as high temperature resistance, friction resistance, electrical conductivity, thermal conductivity and corrosion resistance, etc., but different from the general carbon materials, its shape has significant anisotropy, soft, can be processed into a variety of fabrics, along the direction of the fiber axis shows very high strength. Carbon fiber specific gravity is small, so there is a high specific strength.
CarbonFiber has shown a small growth every year, but still has a stable special fixed market and demand for use. The use of carbon fiber varies by country, with the United States primarily developed for defense and aerospace, while Japan is used for sports and leisure equipment, and is expected to grow significantly in environmental applications in the future. CarbonFiber will open another new era according to the product design and combination of special other materials.
5. The main uses of carbon fiber
Carbon fiber can be processed into fabrics, mats, mats, tapes, paper and other materials. In addition to carbon fiber used as insulation materials, generally not used alone, more as reinforcing materials added to the resin, metal, ceramics, concrete and other materials, constituting a composite material. Carbon fiber reinforced composite materials can be used as aircraft structural materials, electromagnetic shielding in addition to electrical materials, artificial ligaments, such as body substitute materials, as well as for the manufacture of rocket shells, motorized boats, industrial robots, automotive leaf springs and drive shafts.
Carbon fiber is a dual-use new material, belonging to the technology-intensive and politically sensitive key materials. Previously, the United States-led Paris Coordinating Committee (COCOM), the then socialist countries to implement the embargo blockade policy, in March 1994, COCOM has been dissolved, but the shadow of the embargo blockade is still hanging over the sky, the advanced carbon fiber technology is still not attracted to come in, especially high-performance PAN-based filament technology, even if China's entry into the WTO, the situation will not be a major change. Therefore, in addition to the country continue to self-reliance in the development of carbon fiber industry, there is no other choice. Therefore, foreign countries, especially Japan and South Korea, which are leading in carbon fiber production technology, have been maintaining a rather cautious attitude towards the export of carbon fiber materials and products from China, and only a small number of Chinese enterprises have been able to establish a cooperative relationship with them and have import channels for their products.
Currently the world's carbon fiber production reached more than 40,000 tons / year, the world is mainly Japan Toray, Toho Rayon and Mitsubishi Rayon three companies as well as the U.S. HEXCEL, ZOLTEK, ALDILA three companies, as well as Germany's SGL SGL Group, South Korea's Tae Kwang Industry, Taiwan Province of China's Formosa Plastics Group, a small number of units have mastered the production of carbon fibers Core technology, and there are large-scale production. At present, there is no annual output of 100t in the motherland of large-scale carbon fiber plant, most of them are still in the pilot amplification stage. It is worth mentioning that China's Taiwan Province of Formosa Plastics Group, in the mid-80's years from the United States Hitco introduced a hundred tons of carbon fiber production line, digested, absorbed and supporting the rapid development of Formosa Plastics production increased very quickly, but the improvement in the quality of carbon fibers is not large.
China's research on carbon fiber began in the 1960s, the 1980s began to study high-strength carbon fiber. Progress has been slow over the years, but some achievements have been made. Entering the 21st century since the development of faster, Anhui Huawan carbon fiber company took the lead in the introduction of 500 tons / year of raw silk, 200 tons / year PAN-based carbon fiber (only Toray carbon fiber T300 level), so that China's carbon fiber industry has entered the industrialization. Subsequently, a number of manufacturers have joined the ranks of carbon fiber production. According to incomplete statistics, at present, China has 12 production scale of different sizes (5-800 tons / year) of PAN-based carbon fiber manufacturers, with a combined production capacity of 1,310 tons / year, the product specifications for the 1K, 3K, 6K, 12K.
However, due to the fact that some companies do not have the original wire can be burned, the actual total domestic production of carbon fibers is less than 40 tons / year, and product quality is not very The quality of the product is not stable, and most of them are not up to the level of T300. Happily, from 2000 China's carbon fiber to technical diversification, abandoned the original nitric acid method of raw silk manufacturing technology, the use of dimethyl sulfoxide as a solvent for one-step wet spinning technology has been successful. At present, the use of independent technology to develop a small number of domestic T300, T700 carbon fiber products have reached the international level of similar products.
With the growing demand for carbon fiber in China in recent years, carbon fiber has been listed as the national chemical fiber industry focus on supporting new products, and has become a hot spot for research and development of domestic new materials industry. According to incomplete statistics, at present the proposed and under construction of carbon fiber production enterprises have 11, with a total production capacity of 7100 tons of raw silk / year, 1560 tons of carbon fiber / year, of which there are four enterprises under construction, with a total production capacity of 1100 tons of raw silk / year, carbon fiber 470 tons / year.
Despite the slow development of China's carbon fiber production, while consumption has been gradually increasing, the market demand is strong. The main uses include sports equipment, general industry and aerospace, etc., of which the use of sports and leisure goods is the largest, accounting for about 80% to 90% of consumption. China's demand for carbon fiber has exceeded 3,000 tons / year, in 2010 will exceed 5,000 tons / year. The main application areas are: mature market aerospace and defense field (aircraft, rockets, missiles, satellites, radar, etc.) and sports and leisure goods (golf clubs, fishing gear, tennis rackets, badminton rackets, archery shafts, bicycles, rowing boats, etc.); emerging markets are reinforced plastics, pressure vessels, building reinforcement, wind power, friction materials, drilling platforms, etc.; to be developed in the market are automotive, medical equipment, new energy etc.
China's carbon fiber composite materials development began in the mid-1970s, after nearly 40 years of development, has made great progress, in the aerospace leading products (bullet, arrow, star, ship) has been widely used. In recent years, China's sports and leisure goods and pressure vessels and other areas of carbon fiber demand is growing rapidly, the rapid development of aerospace technology in urgent need of high-performance carbon fibers and their composite materials, etc., the market demand is even more robust.
In order to meet the growing demand for carbon fiber in the domestic market, the localization and scale of China's carbon fiber industry should be realized as soon as possible. To this end, we must accelerate technological innovation, master the core technology; accelerate the development of raw silk technology, development of high-purity raw silk; strengthen the application of research and market development, and further expand the application areas. Carbon fiber in China has great prospects for development, but should sum up the development of polyester and other chemical fiber lessons learned to avoid blind development, to achieve healthy development.
In order to manufacture large aircraft and the development of aerospace industry, our country must also as soon as possible to achieve high strength in the model of carbon fiber industrialization. However, because high-performance carbon fiber is the development of aerospace and other cutting-edge technology essential materials, long-term by the United States-led Paris Coordinating Committee blockade. Although the PCC was dissolved in March 1994, the shadow of the embargo still exists. Even if the embargo is lifted on our country, the beginning can only be general-purpose carbon fiber, and will not sell us high-performance carbon fiber technology and equipment.
Therefore, the development of high-performance carbon fiber must rely on our own. China's chemical fiber industry, "Eleventh Five-Year" development plan put forward "to increase the number of major shift to vigorously develop high-tech fibers," especially high-tech fiber materials related to national industrial security as a top priority, and carbon fiber is listed as a Carbon fiber has been listed as the first high-tech fiber varieties that the country urgently needs to break through in a short time, which creates conditions for the development of carbon fiber in China. We should seize this opportunity, be self-reliant, make efforts to innovate, and develop carbon fibers with our own intellectual property rights in order to meet the ever-increasing market demand. The national "863 plan" and the relevant ministries and commissions are concerned about the development of China's carbon fiber industry and its pace of industrialization, and to give strong support, many materials experts have done a lot of solid work. During the "11th Five-Year Plan" period, China has launched the related "973 Program". I believe that the "Eleventh Five-Year" will be the golden age of China's carbon fiber industry industrialization.