September 30, 2018 Source: Carbon Fiber Society

From September 27th to 28th, the “2018’ National Carbon Fiber Industry Development Conference” hosted by China Chemical Information Center was held in Kunming. With the theme of “Application Innovation Industry Development”, the conference invited authoritative experts in important downstream fields such as aviation, satellite, ship and ship, high-pressure gas cylinders, fan blades and automobiles to introduce the latest applications and requirements of carbon fiber composite materials. Discussions on the production and application of carbon fiber tows and the research of biomass carbon fiber.

Demand increased by 13% to 20% annually, promoting domestic carbon fiber power

Carbon fiber and its composite materials are key national strategic new materials. In recent years, the carbon fiber and its composite materials industry has achieved rapid development. It has broken through the industrialization of thousands of tons of high-performance fibers such as T700 and T800, marking that the domestic carbon fiber industry has possessed downstream high-end fields such as aerospace and military equipment. The application basis of the large tow carbon fiber has also achieved remarkable results in the past two years. The Jilin Chemical Fiber 2000-ton production line has been successfully tested at the end of last year. Shanghai Petrochemical also successfully developed the polymerization of 48K large tow carbon fiber in the near future. The spinning and oxidizing carbonization complete process technology provides support for the wide application of domestic carbon fiber in the fields of automobiles, rail transit and wind power blades.

In the speech, Director of China Chemical Information Center, Tax Min pointed out that although the development of China's carbon fiber and its composite materials has shown a good trend, there is still a gap compared with developed countries. The monopoly and blockade of core technology by developed countries has made China's carbon fiber production technology and equipment level lag behind foreign countries as a whole, and cannot meet the needs of high-end fields such as national major equipment. The influx of domestic capital into the carbon fiber field has led to low levels of redundant construction and serious homogenization. There are still many problems in technical equipment and downstream product development and application that need to be overcome. With the continuous expansion of the application field of high-performance composite materials, it will force China's carbon fiber industry to accelerate the pace of innovation.

Since 2014, China's carbon fiber demand has grown at an average annual rate of 13% to 20%. In 2017, China's total demand for carbon fiber increased by 20% compared with 2016, which is higher than the worldwide growth level. In 2017, the import volume of carbon fiber was 16,087 tons, a year-on-year increase of 0.8%. The growth of import volume slowed down compared with last year. This indicates that demand is growing, import volume is growing slowly, and the proportion of domestic fiber market is gradually increasing, indicating that domestic carbon fiber supply begins. work hard. At present, the domestically produced GQ3522 (T300 grade) and GQ4522 (T700 grade) carbon fiber industrial scale production, QZ5526 (T800 grade), QM4035 (M40J grade) carbon fiber engineering production; GQ4522 high performance carbon fiber breaks through the dry spray wet spinning process Industrial production and application are accelerating; in addition, domestically developed wet spinning GQ4522 carbon fiber preparation process, the product has been applied in the aviation field; under laboratory conditions, QZ6026 (T1000 grade), QZ6526 (T1100 grade), QM4050 (M55J grade) carbon fiber has broken through key preparation techniques, but there is still a long way to go before it can be stabilized.

Although China has solved the problem of carbon fiber “from scratch”, how to achieve “from strong to strong” requires more support from the state, and it still needs constant exploration from the government and the whole industry. Ma Quansheng, deputy chief engineer of Guangwei Composite Materials Co., Ltd. gave such insights on the problems in the domestic carbon fiber field: (1) hidden hidden dangers of industrial disorder; (2) different treatments for the same country; (3) obvious short equipment; (4) The high price of electricity weakens the advantage; (5) The dependence on imports depends on production. Ma Quansheng believes that China's carbon fiber industry is still in the development stage. The more high-tech strategic industry, the easier it is to be caught by people. If you want to change the passive situation, you need to mobilize many forces to invest in the key to master the core technology. Subject to people. From the point of view of private enterprises, due to their identity and attribute of asset rights, private enterprises cannot obtain the corresponding conditional support for each key model (such as the inability to enjoy the subsidy for production line construction, equipment technology reform, etc.). Judging from the current actual situation in the Chinese market, most carbon fiber enterprises are private enterprises. These private enterprises are mainly carrying huge cost pressures when they face the investment property of “large carbon fiber investment and long return period”. At the same time, he suggested that in the future, China's carbon fiber industry should focus on: industrial integration, key support; no question of origin, support for leading; electricity price subsidies, targeted support; military-civilian integration, deep advancement.

Zhang Haiou, general manager of Jilin Carbon Valley Carbon Fiber Co., Ltd. introduced that in 2017, the total demand for carbon fiber (including products) in China totaled 23,487 tons, of which the demand for carbon fiber in large tow reached 5,960 tons, accounting for 25%. The demand for carbon fiber applied to wind turbine blades reached 3,060 tons, accounting for 12% of China's total demand. It shows that large tow carbon fiber has great potential in the Chinese market. It can be mainly applied to high-end fields such as aviation carbon fiber composite materials, emerging strategically important basic materials, and industrial fields such as new energy vehicles and rail transit. Zhang Haiou said that the industrialization of large tow carbon fiber raw silk should focus on the following developments: development of large-capacity stable continuous high-efficiency polymerization, homogenization of spinning dope, high-speed spinning, effective control of raw metal content, raw wire low cost Technology, large-scale, high-stability technology.

In 2017, the domestic carbon fiber theoretical production capacity is 26,000 tons, and the sales volume is 7,400 tons. China's carbon fiber production is still dominated by small tow carbon fiber, which has a certain scale. The tow type is mainly concentrated in 1K, 3K, 6K, 12K, etc. Tow, the 24K and larger tow models with better market prospects are still blank. Ma Renlong, deputy general manager of Jilin Jinggong Carbon Fiber Co., Ltd. believes that differentiated products should be added to improve the competitiveness of domestic carbon fiber. Whether it is domestic or foreign, the application of large tow carbon fiber composite materials is the majority in the industrial field. In the future, it will show a large-scale growth in the automotive field, pressure vessels, wind turbine blades and other industrial fields; especially in wind power, automotive fields, pressure vessels. Explosive growth is expected, and in industrial applications, the significant low-cost advantages of large tows can help companies improve their profitability.

Expansion of application areas, forcing the industry to accelerate innovation

Liao Zilong, deputy chief engineer of AVIC Composites Co., Ltd. pointed out that the composite material has become the main structural material of civil aircraft. According to the statistics of the International Composites Association, in the comprehensive cost of aerospace composite structure manufacturing, materials are 15%, laminates are 25%, assembly is 45%, curing is 10%, and fasteners are 5%. Therefore, low-cost manufacturing technology has become a major factor affecting the further expansion of composite materials. Liao Zilong pointed out that the low-cost ways of aviation composite materials can be divided into the following types:

Liao Zilong said that at present, foreign countries are vigorously developing low-cost composite non-autoclave forming technology; non-autoclave forming technology has been applied to civil aircraft secondary bearing structure, and is developing towards the application of main bearing structure.

In terms of ship and ship applications, Li Xiang, a researcher at CS26, said that the hull structure of high-performance ships has high requirements for fatigue resistance, long life and impact resistance. Li Xiang pointed out that the current application of carbon fiber composites faces many common problems that need to be solved. First, the long-term reliability of electrochemical connection between carbon fiber composites and metal structures: in the field of ships and deep submersibles, carbon fiber composites and metal structures are The seawater environment is highly susceptible to electrochemical corrosion due to potential differences. Secondly, the performance degradation and life assessment technology of carbon fiber composites under high-deep sea stress: no matter the submersibles or submarines, carbon fiber inevitably faces seawater infiltration/hygroscopicity in shell application, and its performance degradation law is insufficient in deep sea. Again, the process technology: including large thickness carbon fiber composite curing stress control technology and low-cost large tow carbon fiber permeability technology.

Mr. Mi Kuan, director of the technical center of Sinoma Technology (Chengdu) Co., Ltd., introduced that gas cylinders are a major gas storage pressure vessel commonly used in the fields of automobile, chemical, machinery, aerospace, shipbuilding and marine development. An important form of the bottle. Composite gas cylinders are wound gas cylinders that are wound on a metal or non-metallic liner and are wound around a fully wound fiber material. Compared with metal containers, composite gas cylinders are light in weight and have a high specific strength of fiber materials, which improves the load carrying capacity of the gas cylinder while reducing weight. The higher the working pressure, the greater the weight advantage; for high pressure hydrogen storage hydrogen cylinders such as 35MPa and 70MPa, carbon fiber full-wound composite gas cylinders, namely type III and type IV cylinders, are generally considered. In addition, carbon fiber composite gas cylinders have good environmental resistance, service life of up to 30 years (glass fiber life is generally 15 years), high safety, fatigue failure mode before blasting. Mi Kuan believes that with the continuous development of new energy vehicles, especially the development of hydrogen energy vehicles, the demand for high-pressure composite gas cylinders will increase, due to the high pressure and light weight of type III and type IV cylinders. The ratio will continue to increase.

In 2017, the global demand for carbon fiber (including products) totaled 84,200 tons, of which the demand for carbon fiber in large tow (above 24K) reached 34,900 tons, accounting for 42%. The demand for large tow carbon fiber applied to wind power blades reached 19,800 tons, accounting for 23% of the total global demand, and the growth trend is obvious. According to reports, the application of carbon fiber wind power can be divided into: large grams of prepreg, carbon fiber fabric and reinforced carbon board. Zhao Qingxin, a doctor of Jiangsu Aosheng Composite Materials Technology Co., Ltd., said that the use of carbon fiber wind power blades has many advantages, such as: making the fan blades longer, generating more power, reducing the weight of the motor, and auxiliary facilities can also be slimmed down. Transportation, installation, etc. are less difficult, and the cost is reduced. At the same time, Zhao Qingxin pointed out that carbon fiber has higher cost, poor toughness and more difficult to infiltrate than glass fiber. Therefore, in the future, it should focus on the development of large tow carbon fiber, its process innovation, and thermoplastic carbon fiber composite. The direction of the material blades and the recovery of carbon fiber composite materials.

Chen Youwei, Nuclear Energy Materials Engineering Laboratory, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, introduced the “Simulation and Special Equipment Development for Nuclear Ceramic Composites”.

Good development still needs standard first

Ma Dan, secretary of the National Fiberglass Product Quality Supervision and Inspection Center and the National Carbon Fiber Standardization Technical Committee of Nanjing Glass Fiber Research and Design Institute, pointed out that there are five major problems in the current carbon fiber standardization work: First, carbon fiber is involved in the production and research departments, and the application industry is wide. It is also a military-civilian dual-use product, each with its own system. Second, there is a lack of specialized standardization technology organizations for a long time. There is a lack of comprehensive system planning for standards, and there are multiple standards in parallel. Some standards are repeated and even contradictory. Third, The basic standards are lacking, the terminology and product specification code are not uniform, and the understanding of the standard and the usage habits are different, resulting in the comparison of the test results of the same material is not strong. Fourth, the user does not understand the ISO standard, the national standard and the ASTM standard; The material standards are not perfect, which affects and restricts the development and performance improvement of the products. The new standards are not sufficiently effective. Some of the test standards are stuck in the enterprise/unit's own standards, which affects the promotion and use of new standards.

According to reports, China's carbon fiber standardization work can be divided into three stages:

The first phase (1980-1998)

The production of basic carbon-free fiber in China is mainly to meet the matching requirements of military carbon fiber composite materials, and three test method standards have been formulated.

The second stage (1999-2010) promotion stage

We have comprehensively developed and developed China's glass fiber, carbon fiber and other reinforcing fiber standard systems, and formulated a series of standards from the definition of terms to test methods and various types of products, and promulgated and implemented, initially forming a standard system for reinforcing materials in China.

The third stage (2011-2018.5) development stage

According to the requirements of the rapid development of the carbon fiber industry, in response to the characteristics and application requirements of carbon fiber materials, scientific research and development led the development of standards, and developed test methods involving carbon fiber basic characterization parameters and physical, chemical, mechanical, electrical and other performance, as well as technical standards for conventional products. .

Ma Dan pointed out that there are 8 points in the future key action plan for carbon fiber standardization in China:

1. Do a good job in the organization and construction of the National Carbon Fiber Standardization Technical Committee;

2. Develop and improve carbon fiber technical standards as soon as possible;

3. Develop carbon fiber product standards for high-strength, high-modulus carbon fiber multiaxial fabrics, preforms, stretch fabrics, prepregs, etc. for large composite structural members;

4. Develop standards related to carbon fiber composite materials and metal joints;

5. Explore the establishment and implementation of the Standard Qualification Plan for the integration of military and civilian carbon fiber and composite materials around the needs of military and civilian integration applications;

6. Improve the database of carbon fiber and composite products;

7. Plan to establish a carbon fiber laboratory alliance or test platform to promote resource sharing among carbon fiber R&D institutions, manufacturing companies and inspection and testing institutions;

8. Promote the transformation of results to international standards, propose high-quality international standards, and strive for China's right to speak on carbon fiber international standards.

Professor Zheng Zhifeng, a doctoral tutor at Xiamen University, introduced the “biomass carbon fiber”.

Li Yujia, general manager of Beijing Henghedun Intellectual Property Agency Co., Ltd., made a report on the registration of international trademarks.

During the meeting, the delegates had an in-depth exchange and the atmosphere was warm.