Since 2014, Japan and the United States have been focusing on the commanding heights of the new generation of carbon fiber products in response to the needs of the next generation of aerospace products.
In January 2014, Mitsubishi Rayon introduced the MR70, which is basically equivalent to T1100G.
In March 2014, Toray Corporation of Japan announced the development of high-strength and high-modulus carbon fiber T1100G; In November 2107, Toray Corporation of Japan developed a new carbon fiber variety Z600; In November 2018, Toray Corporation launched an improved high-mode series Product MX.
In March 2019, Hexcel Corporation of the United States announced its high-strength, high-modulus carbon fiber HM50, which has far higher performance than the IM7 currently used by the US military, but the strength is still lower than MR70 and T1100G.
The development of new-generation products in the United States and Japan has made breakthroughs one after another, and the leading edge has increased. As a strategic material for carbon fiber products, China must develop independently and pay close attention to major foreign developments.
1. The three major Japanese manufacturers focus on the civilian market and adopt a forward-looking iterative development model
Japan's development of carbon fiber products is mainly aimed at the high-tech industry, focusing on the civil aerospace market. Civil aircraft product types are diverse, fiercely competitive, and the speed of replacement is fast. It promotes the "small step and fast run" of Japanese carbon fiber products and the series development. Its capacity, performance, and price are ahead of the United States. Japan's carbon fiber research and development and innovation are led by enterprises. The main manufacturers are Toray, Teijin Toho Rayon and Mitsubishi Rayon. Among them, Toray's research and development strength, quality and production capacity are in the world's leading position. Its global market share of carbon fiber products reaches more than 30%. Teijin Toho Rayon Company and Mitsubishi Rayon Company together account for about 40% of the world's total. %.
1. Development trend of Toray's products
The company's carbon fiber production mainly includes T series (high-strength T300 to T1100G), M series (high model M30 to M70), MJ series (high model improvement, M40J to M70J) and MX series (high model improvement). Among them, MJ and MX series are new products developed by the company on the basis of high modulus carbon fiber M series and breaking through technical bottlenecks.
High-strength T series products: mainly used for aerospace structural components such as wing and fuselage that have high requirements on strength. Development Trend:
The first is mature application of the second generation products. In the 1980s, the second-generation T700, T800, and T1000 high-strength medium-mold carbon fiber series were developed. At present, T800 (tensile strength 5.88 GPa, modulus 294 GPa) is the most widely used commercial carbon fiber in aerospace and other fields. It is widely used in the fuselage and wings of A350 and B787 passenger aircraft. The first generation T300 has been gradually phased out. .
The second is the new third-generation T1100G, which fully surpasses the second-generation products. In March 2014, Toray announced the successful development of T1100G carbon fiber (tensile strength 7GPa, modulus 324GPa), marking the third generation of high-strength and high-mold carbon fiber products in Japan. In March 2017, the company broke through the resin and sizing process and launched its supporting T1100G / 3940 epoxy prepreg. Compared with the second-generation T800 / 3900-2 prepreg, this latest prepreg has improved tensile strength and impact resistance by 30%. This new type of carbon fiber composite material may reduce the weight of components by 20%, and has good application prospects on structural components such as wings, fuselages, and engines.
High-mode M series products: Mainly used for aerospace structural components that have high requirements on stiffness, especially helicopter rotors, satellites, and missile casings, which have slightly lower strength requirements and high deformation requirements. Development Trend:
The first is to expand to the MJ series. In the mid-1980s, in order to meet the needs of equal emphasis on high strength and high modulus of aerospace main load-bearing structural parts, on the basis of M40, M50 and other high-model carbon fiber series in the 1970s, M40J-M60J and other high-strength high-model "MJ" Products. M65J tensile strength is 3.63GPa, the modulus can reach 640GPa, M70J tensile strength is 3.5GPa, and the modulus can reach 680GPa.
The second is the emergence of the MX series, which has greatly improved its strength. In November 2018, Toray launched a new MX series. This series is a nano-scale graphite crystal structure that strictly controls the graphitization process, and increases the tensile strength and tensile modulus to a new height in parallel. The first MX series product is M40X, with a tensile strength of 5.7 GPa and a tensile modulus of 377 GPa. The tensile strength is about 30% higher than that of M40, while maintaining the equivalent tensile modulus. Toray plans to introduce prepregs containing MX series carbon fibers, which will have significant improvements in tensile strength, compressive strength, and impact resistance.
2. Teijin Toho Rayon Company's product development trend
According to the carbon fiber modulus, Teijin Corporation divides its products into three categories: standard modulus (which has been phased out in aerospace), medium modulus and high modulus. The company's best-performing mid-mold product is IMS65, which has performance comparable to Toray T800; the best-performing high-mold products are UMS40, UMS45, whose performance is comparable to Toray M40J, M50J, and Toray M70J, MX series There is still a large gap in products; the third-generation high-strength high-modulus products have not yet been launched.
3. Mitsubishi Rayon Product Development Trend
Mitsubishi Rayon's carbon fiber products can be divided into high-strength low-mode, high-strength medium-mode, high-strength high-mode and high-mode series according to the modulus. HT-TR30 and HT-TR50 are representative products of high-strength and low-mode, of which HT-TR30 is equivalent to the performance level of T300 and HT-TR50 is equivalent to the performance level of Toray T700; representative products of high-strength medium mode are IM-MR60 (performance is between Toray T700 ~ T800, close to T800); the latest product of high strength and high modulus is IM-MR70, the tensile strength can reach 7GPa, the modulus reaches 324GPa, and the performance is equivalent to T1100G. The gap between high-model series products and Toray is large, and the best product HM-HS40 is only equivalent to Toray M40J.
2. The United States strives to control its own military market, and the government actively participates in technology research and development.
The United States carbon fiber products have a very deep national security background. Under the situation that Japan dominates the civilian market and many military forces also use Japanese carbon fiber products, it has long insisted on independent research and development, procuring domestic products as much as possible to meet the military market demand, and maintaining the domestic military carbon fiber products. Circulation, basically achieve autonomy and control.
Government agencies mainly based on the Defense Advanced Research Projects Agency (DARPA) of the United States Department of Defense have guided and funded many research institutes and SMEs in carbon fiber technology innovation. Among them, Cytec Industries and Hershey Composites have stood out and become the main military carbon fiber suppliers in the United States. After Cytec Industries was acquired by Solvay in Belgium in 2015, Hexcel became the largest military carbon fiber supplier in the United States.
Hexcel currently has a series of carbon fiber products, including the AS series of high-strength medium-low mode, the IM series of high-strength medium-mode and the HM series of high-mode. The representative brands of the AS series are AS4 and AS7 (the performance is equivalent to Toray T700) The representative brands of the IM series are IM7 (the performance is slightly lower than the Toray T800), IMA (the performance is equivalent to the Toray T800), IM8, IM9, IM10, the representative brands of the HM series are HM63, and the performance is only comparable to the Toray M46J.
Hexcel's high-strength carbon fiber product series has been widely used in U.S. military fighter aircraft and spacecraft, of which AS4 and IM7 are the most widely used. The composite materials formed by the matching of two carbon fibers with epoxy resin and Shuangma resin have been widely used in the US military F The -22A and F-35 stealth fighters have also been procured in Europe for A400M military transport aircraft and A350XWB wide-body passenger aircraft. In order to break through the key technology of the third-generation high-strength and high-modulus carbon fiber, DARPA stepped in again, and launched the "Advanced Structural Fiber" project in 2006, bringing together the nation's leading scientific research forces to develop the next-generation structural fiber mainly composed of carbon fiber.
The Georgia Institute of Technology in the United States has developed a new carbon fiber with a strength of 5.5 to 5.8 GPa and a modulus of 354 to 375 GPa under the funding of this project.
In 2009, Hershey also successfully developed IM10 with a strength of 6.8 GPa and a modulus of 310 GPa. The strength is equivalent to T1100G but the modulus is slightly lower. In March 2019, the company exhibited the newly developed high-strength and high-modulus carbon fiber HM50 at the European Composites Exhibition. Its strength reached 5.86 GPa and its modulus reached 345 GPa. Compared with IM10, the strength was greatly reduced and the modulus was significantly increased. The strength and modulus are far higher than the IM7 currently used by US military equipment.
It is worth noting that at present U.S. military equipment still needs to use some Japanese carbon fiber products. Although it is from an ally, the U.S. government is still highly vigilant about this: The U.S. Department of Defense led the completion of the U.S. defense industry foundation and supply chain assessment in October 2018. The United States “proposes that some special and specialized carbon fibers are overly dependent on Japan and Europe ’s exclusive supply, indicating a serious weakness in the Ministry of Defense ’s supply chain.”
3. Inspiration suggestions
Carbon fiber is a key raw material for advanced aerospace composite materials. Japan and the United States have long dominated the high-end product market, and both have listed carbon fiber as a strategic material. The technology is highly confidential and the products are embargoed on me. On the other hand, carbon fiber products with both higher strength and higher modulus will be a highly competitive technical highland in the national defense and military industries in the future. Japan and the United States are still at the forefront of carbon fiber technology development. Among them, Japan ’s high-strength carbon fibers and high-modulus carbon fibers are leading the world, and new product launch speeds and performance indicators are clearly ahead of the United States. From the perspective of the development model, the development of Japanese carbon fiber products is mainly caused by the self-issuance of enterprises attracted by the existing and potential demand of the civil aerospace and other markets; the development of carbon fiber products in the United States has long been aimed at the needs of the domestic military market. The investment of resources played an important role.
The development of China's carbon fiber industry should draw on the experience of Japan and the United States, face both the military and civilian markets, and adhere to the combination of government guidance and support and corporate R & D.
On the one hand, government guidance and investment should be used to clarify the possible equipment requirements for materials, to ensure the stability of second-generation product production and to break through the third-generation product technology, to resolutely stick to the goal of achieving industrial transformation, and to fully consider domestic procurement. Improve the autonomous and controllable level of our military equipment materials;
On the other hand, China's carbon fiber enterprises should be encouraged and supported to actively participate in market competition, take the initiative to target the commercial market to research and develop products, promote the transformation and application of related military technologies, enrich product lines, continue to upgrade, and nurture equipment development.
In general, if we fully grasp the development model and situation of carbon fiber products in Japan and the United States, we can give full play to the advantages of the system that can focus on efficient affairs and take advantage of the historic opportunities that the military-civilian integration strategy has fully spread and advanced. The industry is expected to accelerate the realization of new technological breakthroughs and large-scale and stable production, and embark on a benign sustainable development track.