"Feitian" Is Armed With High-End Dream, And Domestic Carbon Fiber Is Fighting For The Aerospace Application Market

"Our journey is the sea of stars."

On June 17, Shenzhou 12 manned spacecraft successfully launched three astronauts, Nie Haisheng, Liu Boming and Tang Hongbo, into space. After the shenzhou-12 manned spacecraft successfully achieved autonomous rapid rendezvous and docking with Tianhe core module, three astronauts entered Tianhe core module. This is the first time that Chinese have entered their own space station.

"Shenzhou No.12 set sail to the sun, straight to Xiaohan! Like everyone else, I witnessed this exciting and exciting historical moment in front of the TV. " Foreign Ministry spokesman Zhao Lijian said at a regular press conference that the exploration of the vast universe is the common dream of all mankind.

The continuous breakthrough and development of China's manned space technology is inseparable from the hard work of spacemen and the "escort" of advanced new materials.

According to the information disclosed by China Aerospace Science and technology group, carbon fiber control rods with high specific strength and comfortable handle are used on the spacecraft. In the process of launch and return, the astronaut's body is firmly bound to the seat, and the body can not lean forward to complete the operation of various devices on the instrument panel. The control rod is to solve this problem. The control rod body is designed to be infinitely retractable, and the astronauts can adjust the length of the control rod arbitrarily within a certain range according to the site conditions.

From the global perspective, aerospace has been the key application field of carbon fiber and its composites. The important "mission" of advanced new materials is to meet the major national strategic needs such as "deep space and deep sea".

Now, after 20 years of rapid industrialization, what new breakthroughs have been made in the application of carbon fiber in the field of aerospace in China? What is the future development trend?

"Lightweight" of aerospace equipment

Favor carbon fiber composite

In the global aerospace field, "one generation of materials, one generation of equipment" is a well-known saying.

An aviation industry insiders pointed out that aviation materials are the basis for the development of aviation industry. The development of aviation industry is closely related to the innovative application of airframe materials, structural materials, engine materials and various component materials. The use of advanced materials is an important guarantee to achieve high performance, lightweight, high reliability, long life and low cost.

Zhang Xuejun, deputy chief engineer of AVIC Beijing Institute of aeronautical materials, has previously publicly stated that for aircraft and engines, materials require light weight, high strength and high temperature resistance, and the structure should have low defects and high stability. This is a problem that must be solved in the manufacturing of aviation materials.

Carbon fiber composite is a kind of high-tech material with the characteristics of "high performance and light weight".

The person in charge of the R & D Department of a well-known domestic carbon fiber enterprise introduced to the reporter that from the aspect of specific strength, the tensile strength of ordinary steel is about 600MPa ~ 800MPa, while the tensile strength of general-purpose carbon fiber is 3500MPa and above, that is to say, the strength of carbon fiber is about 4 ~ 6 times that of steel. In terms of density, the density of 45 steel is 7.85 g / cm3, while the density of T300 carbon fiber is 1.76 g / cm3, and the density of T700 Carbon fiber is 1.8 g / cm3, which is less than 1 / 4 of steel. This means that the same weight of carbon fiber and steel, carbon fiber can withstand more than 20 times the load of steel. The density of aluminum alloy is about 2.7g/cm3, while the density of carbon fiber reinforced resin matrix composite can be less than 2G / cm3 if it is well prepared. At the same time, carbon fiber has outstanding characteristics of high temperature resistance and corrosion resistance. For example, in the absence of oxygen, carbon fibers can withstand a high temperature of 3000 degrees Celsius, which is difficult for ordinary metal materials to achieve.

Because of its typical characteristics of "light weight and high strength", aerospace has become a key application field of carbon fiber and its composites in the world.

According to the global carbon fiber composite market report 2020 (hereinafter referred to as the report) released by Guangzhou sail Carbon Fiber Technology Co., Ltd., in 2020, the total consumption of carbon fiber in the world of 1068600 tons, the consumption of aerospace industry is 16450 tons, accounting for about 15%. In fact, it has been higher for many years《 According to the report on the global carbon fiber composite market in 2019, the total consumption of carbon fiber in the world was 103700 tons in that year, among which the consumption of aerospace industry was 23500 tons, accounting for 23%. Only in 2020, affected by the global epidemic situation, the foreign civil aviation and business aircraft market will decline seriously, and the consumption of carbon fiber will also decline.

In the field of military industry, carbon fiber composites are widely used in fighter aircraft《 According to the report, in 2020, the global consumption of carbon fiber in the field of military aircraft will be about 2600 tons, accounting for 15.8% of the total consumption of carbon fiber in the field of aerospace.

Because of the strategic value of carbon fiber, foreign countries have been implementing "three blockades" on China's products, technology and equipment in the field of carbon fiber. Key technologies and materials can not be "controlled by others". To ensure the safe supply of independent materials in the field of national defense and military industry has also become the most fundamental motivation for the domestic carbon fiber industry to overcome the technical problems of industrialization step by step.

Since 2005, with the continuous breakthrough of domestic carbon fiber preparation technology and industrialization technology, China's national defense and military industry carbon fiber materials have successfully achieved independent supply support.

According to the report, in 2020, the total amount of carbon fiber used in China's market will be 48851 tons, of which 1700 tons will be used in aerospace (including some imported carbon fibers).

Guangwei composite material is the leader of China's military carbon fiber market. According to the company's financial report in 2020, the company's sales to customer a was 982 million yuan, accounting for 46.42% of the company's total annual sales. The relevant person in charge of the company told reporters: "in the past 20 years, Guangwei has successively undertaken a number of national" 863 Program "projects and major national scientific research projects, becoming the first enterprise in China to realize the localization of carbon fiber core equipment, and the first enterprise to provide domestic carbon fiber to China's defense and military industry. At present, Guangwei is the main supplier of carbon fiber in China's military industry“

"As a strategic material for both military and civil use, the technology of carbon fiber material has a certain degree of subversion, which can make polymer materials become structural materials. If carbon fiber and its composites can be used as alternative materials for equipment, the weight of equipment can be reduced to a certain extent. All kinds of equipment in China need to be upgraded continuously, and lightweight is the eternal theme. Weight reduction of aerospace equipment is done in grams. If the weight of the rocket engine can be reduced, its range will be significantly increased; If the weight of the aircraft can be reduced, its fuel consumption and emissions will be reduced accordingly. This is the main reason why carbon fiber and its composites are becoming more and more popular. " Du Shanyi, an expert in aircraft structural mechanics and composite materials and academician of the Chinese Academy of engineering, said so.

China's civil aviation industry

Accelerate the embrace of independent carbon fiber

Advanced aircraft manufacturing industry is generally known as "the crown of manufacturing industry". In recent years, the application of domestic carbon fiber in civil aviation and aerospace fields has made new breakthroughs. Especially in the past two years, in the face of complex and changeable international situation, it is the general trend to accelerate the use of domestic self-made composite materials in the field of civil aviation.

Commercial aircraft is the top priority. From the global market point of view, over the past few decades, well-known airlines in developed countries have cooperated with carbon fiber "giants" in the development of commercial aircraft, which has made the commercial aircraft become the dominant application field of carbon fiber composites. For example, carbon fiber composites are widely used on Boeing 787 and Airbus A350.

According to the report, in 2020, the consumption of carbon fiber in the global commercial aircraft sector will be about 8700 tons, accounting for about 52.9% of the total consumption of carbon fiber in the global aerospace field.

In China, with the continuous promotion of domestic large aircraft manufacturing projects, the cooperation with domestic carbon fiber has been going on. In particular, by 2020, this process has started to accelerate.

"Since August 2020, Toray, a global carbon fiber giant, has cut off carbon fiber supply to China. This makes us more clearly realize that under the current situation, the autonomy of material supply in the field of civil aviation must also be in our own hands. " The person in charge of a carbon fiber enterprise sighed to the reporter.

The person in charge of the typical structure Department of COMAC composite material center has previously publicly stated that the use of composite materials on large passenger aircraft is expanding from secondary load-bearing structures such as tail wings to main load-bearing structures such as fuselage and wings. Composite materials are widely used in C919 large domestic aircraft and cr929 in China Russia wide body aircraft project. At present, composite materials are mainly used in the rear fuselage section of C919, and the amount of composite materials accounts for about 12%. Next, in addition to the nose, the cr929's fuselage, wing and tail are planned to use composite materials, with an estimated consumption of about 50%.

The reporter learned in the interview that many carbon fiber enterprises in China have participated in the domestic large aircraft project. The person in charge of Guangwei composite materials publicly said: "the PCD verification of Guangwei carbon fiber products for C919 application has been carried out for many years, but it has not been put into mass production and application at present; Material preparation is in progress for the application of cr929. "

Besides commercial aircraft, helicopter and UAV are also important application fields of carbon fiber and its composites, such as plateau helicopter, UAV for pesticide spraying in agricultural field, etc.

According to the report, in 2020, the global helicopter consumption of carbon fiber will be about 1500 tons, accounting for 9.1% of the total amount of carbon fiber used in the global aerospace field; The global consumption of UAVs is 750 tons, accounting for about 4.6%.

In these aspects, the application of domestic carbon fiber is also expanding in recent years. From May to June this year, Guangwei composite announced that it has successfully delivered the first TP500 unmanned transport aircraft's rear fuselage, tail wing and front fuselage to avic-1 and Yitong UAV Systems Co., Ltd., thus realizing the complete delivery of the fuselage and tail wing of the first TP500 unmanned transport aircraft.

It is understood that TP500 unmanned transport aircraft is mainly used in the freight unmanned transportation market. The whole machine is mainly designed and manufactured with composite materials, and adopts advanced bonding integration process for assembly and connection, so as to minimize the structural weight and reduce the production cost. The aircraft is mainly used to meet the demand of unmanned freight transport market in China's inland and islands, as well as Southeast Asia, the Middle East, North Africa and other countries and regions. It can also be refitted to perform remote sensing mapping, human shadow engineering, communication support, emergency rescue and other tasks.

According to the person in charge of Guangwei composite, the first aircraft design and Research Institute of aviation industry is the overall research and development unit of the UAV, and Yitong UAV System Co., Ltd. is the overall assembly unit. Guangwei composite undertakes the research and development tasks of the main materials, parts and large parts of carbon fiber prepreg, and delivers them to customers in the form of large parts for final assembly and debugging.

"In recent years, Guangwei composite has actively developed UAV composite business based on its own advantages of carbon fiber and composite industry chain. At present, it has the ability to develop composite materials from carbon fiber and prepreg to composite parts and complete machine. The company has accumulated rich experience in UAV manufacturing and civil aviation system construction, and has successfully delivered AR500 series UAV helicopters, TP500 unmanned transport aircraft, high altitude solar powered long-range UAV and other UAVs to customers The person in charge said.

The person in charge further said: "AR500 series and TP500 series UAVs use fiber and prepreg produced by Guangwei, mainly small tow T700 Carbon fiber. The complete delivery of the first TP500 unmanned transport aircraft is another important embodiment of the company's continuous improvement in research and development and production of carbon fiber composites after the delivery and batch production of unmanned helicopters. On the whole, the civil unmanned transport aircraft market has broad development space in the future. Guangwei will also continue to make efforts to give full play to the company's integrated advantages in the design, molding and manufacturing of carbon fiber, prepreg and composite materials, and actively cooperate with relevant design and operation, so as to realize the commercialization goal as soon as possible. "

In addition, Lin Gang, general manager of Guangzhou Saio Carbon Fiber Technology Co., Ltd., told reporters: "in China, the use of UAVs in the agricultural field is also increasing in recent years. For example, Xinjiang cotton farmers use more and more UAVs to spray cotton. These fields are very potential markets and new opportunities for domestic carbon fiber. "

China's new generation launch vehicle

Domestic carbon fiber will be used

According to the report, in 2020, the consumption of carbon fiber in the global aerospace field will be about 300 tons, accounting for about 3% of the total consumption of carbon fiber in the global aerospace field.

In the field of aerospace in China, the application of domestic carbon fiber and its composites is also breaking through. Recently, the low temperature mechanical test of the domestic t800h carbon fiber and the 3.35M diameter composite liquid oxygen tank designed and developed by Shanghai Aerospace eighth Institute have been successfully completed.

Shanghai Aerospace said that this is the first time that domestic carbon fiber has been used in large-scale composite liquid oxygen tanks in China, and it has passed the test verification of engineering application magnitude, indicating that China's composite liquid oxygen tank has preliminary engineering application capacity, and it is expected to realize engineering application in China's new generation launch vehicle.

Shanghai Aerospace pointed out in its official wechat public number that the tank, which accounts for more than 60% of the weight of the rocket structure, can be called the "big" part of the rocket. The lighter the tank is, the more payload the rocket can carry, and the greater the rocket's carrying capacity. Therefore, the weight of the tank has always been a matter of concern to structural designers. In recent years, from traditional aluminum copper alloy to high-strength aluminum lithium alloy material, the iteration of tank structural materials has helped the rocket achieve the "small goal" of weight reduction, but for structural designers, this is far from enough. Since 2016, the team of Shanghai Aerospace eighth Institute has focused on carbon fiber reinforced composites with higher mechanical properties, and has carried out relevant scheme demonstration work.

Chen Jia, structural system designer of the 805 launch vehicle, said that the specific strength of the composite material can be increased by more than 50%, and the weight of the composite material is expected to be reduced by 30% compared with the metal tank. Moreover, the integrated design method can greatly simplify the manufacturing process and quality control links, and achieve remarkable results of reducing cost and increasing efficiency. Take the new generation launch vehicle developed by Shanghai Academy of Aerospace Science and technology as an example. If the weight of the current metal tank can be reduced by 30%, the rocket's carrying capacity will be increased by 6%. That is to say, the rocket can carry an extra load of 300 kg, which is of great significance for the launch rocket whose transport capacity price is in grams.

"The 805 Institute has made a substantial breakthrough in the key technology research of large-scale composite liquid oxygen tank, which makes it practical and feasible to realize the goal of engineering application of composite liquid oxygen tank on China's new generation launch vehicle during the 14th Five Year Plan period." Shanghai Aerospace said so.

Relevant person in charge of Guangwei composite materials introduced to the reporter: "Guangwei broke through the core technology of domestic T800 high-performance carbon fiber in 2013, and realized engineering production in 2014. In the national evaluation of "domestic t800h carbon fiber" and "high strength and high modulus carbon fiber" projects approved by relevant departments, Guangwei has won the first place in China. At present, Guangwei has formed a series of high-strength, high-strength medium modulus and high-strength high-modulus carbon fiber product system, and has built an advanced carbon fiber composite research and development center. Our goal is to continue to provide high-performance carbon fiber, composite materials and products for China's major projects in the fields of aerospace, aviation, ordnance industry and large aircraft. Since the company embarked on the road of carbon fiber technology research and development and industrialization, it has been our unremitting goal to serve the country through industry. "

However, it is worth noting that compared with developed countries, the proportion of carbon fiber and its composites used in aerospace industry in China is still relatively small《 According to the report, in 2020, the carbon fiber consumption in China's aerospace industry will account for about 3.5% of the total carbon fiber application in China's market, and there is still a certain gap compared with the global 15% in the same period.

However, gaps also mean growth potential. From the overall development trend, Du Shanyi stressed: "in the future, carbon fiber and its composites will become more and more important, the demand will be more and more urgent, the role will be more and more significant, and the application fields will be more and more broad."

Lin Gang said: "at present, the intensification of trade friction between China and the United States, and Japan's Toray cut off carbon fiber supply to China, have made China's aerospace field more aware that the civil aviation market must also accelerate the process of independent support of domestic strategic materials. On the other hand, Toray's interruption of supply has given more opportunities to domestic carbon fiber. If we look at the overall development trend of the global carbon fiber application market, although the two years have been hit hard by the epidemic, the future vitality of the aerospace market is still strong. It is estimated that in the next three years, the demand for carbon fiber in civil aviation market can return to the level in 2019. Moreover, when the demand recovers, and carbon fiber and its composites will be widely used in single channel aircraft in the global market, it will continue to stimulate carbon fiber for aviation market. It is estimated that by 2030, the consumption of carbon fiber in the global aerospace market will increase to 80000-100000 tons. Overall, in the next 10 years, the main driving force of global carbon fiber application will be industry, and the auxiliary drive will be aerospace. In terms of technological development, carbon fiber is still a "dual drive" mode for aerospace and industrial applications, and the product specifications driven by each will have its own characteristics. "

(source: China Textile News)