Current situation and Countermeasures of carbon fiber

Jul 30, 2019

The properties and development trend of carbon fiber composite materials conform to the development of the automotive industry, especially with the development of new energy vehicles, carbon fiber composite materials will be more and more widely used in the automobile. In European and American countries, the amount of composite material is about 1/3 of the total output of the country, which is mainly used in the automobile panels (two doors, four cover), secondary bearing components, body and other parts, the amount of which is increasing year by year. Application of carbon fiber composites in the field of automobile Carbon fiber composite material can replace the main bearing structure of the steel for automobile because of its unique strength and rigidity. 

With the development of China's automobile industry, the application of composite materials in the automotive industry in China has been a breakthrough, the annual consumption of automobile composite material is about 100000 tons, but it is mainly used in the non bearing structure of glass steel composite material, automobile composite material manufacturers generally smaller. Carbon fiber reinforced epoxy resin composites in metals that are used in the structure of automobile body instead of large commercial aircraft and high performance cars (such as the Tesla, the BMW I3 and I8) and F1 main bearing force structure on the successful application shows that, the composite can. At present, the domestic automobile enterprises have begun to try to use carbon fiber composite parts to replace the traditional metal parts. Domestic vehicle manufacturers have begun to research and development of composite materials and manufacturing enterprises, to start the production of composite parts design and development, and gradually began to make full preparations for the production. Due to the requirement of bearing capacity, the composite parts (especially the bearing parts, such as the transmission shaft, etc.) of the vehicle are required to design the materials and components. In recent years, aviation composites give full play to the its advantages in the aspects of design, material and fabrication, successively for vehicle plant research and development of the automobile front cabin cover, the trunk cover, tail, heavy automobile plate spring, bus leaf spring, heavy vehicle transmission shaft, full composite bearing type bus body, all composite tanks and other products, some of the products has passed the test.

Current situation and gap analysis of domestic automobile composite industry "Five eleven", "Five" period, the domestic automobile enterprises and scientific research units have jointly developed the four generation of carbon fiber composite material model electric vehicles. Through reverse engineering design technology, the two generation of carbon fiber composite material is used to replace the existing models. The weight reduction effect of carbon fiber composite material and the assembly technology of carbon fiber composite are verified. The design of the main structure of the whole carbon fiber composite material is verified by the forward design. Research and development of the fourth generation car for carbon fiber composite materials in the industrial application of the automobile industry has accumulated valuable experience, open the starting point of domestic carbon fiber composites for automotive applications. In the near future, the aircraft is the first in the country to adopt the fast curing of the pre leaching material with the rapid molding technology, vacuum assisted molding process to prepare the bearing type full composite material electric car body, in which the integrated manufacturing, cost control and manufacturing efficiency and other aspects have achieved good results. At present, the research of carbon fiber composite material is carried out by the domestic automobile engine factory and the spare part supplier. The main focus is on the light weight of the parts, the use of the non continuous fiber forming process, the production of automobile parts has realized the mass production and large-scale application. However, due to the lack of automated production equipment, continuous fiber composite material has not yet formed a production level, especially the body mass production technology. Although enterprises have launched a carbon fiber composite body electric vehicle, but parts, vehicle design, verification and production technology and automatic assembly technology, and quality control are still in the exploration, from carbon fiber composite materials in the automobile industry of large-scale applications there is a certain distance.

Domestic carbon fiber composite material for lightweight automobile manufacturing industry has just started, in the early stages of technology exploration and accumulation. Aviation composites have been associated with China FAW Group Corporation jointly established "Automobile Joint Laboratory of advanced materials", with Beiqi jointly established "Automotive Center for advanced materials technology", aims to develop the automobile composite material parts and components of the research, development and engineering application, and Changan Automobile, BYD group also in the development of cooperation, carry out composite parts research and development for new energy vehicles. Company has developed a series auto parts (composite leaf spring, drive shaft, wheels and other moving parts and engine cover, the trunk cover, the tail wing etc. panel) and the first all composite bus body. In 2014, the aircraft industry has assumed the national "863" project - "CCF-3 - grade carbon fiber composite materials in the field of transport and energy application technology". The main material system is fast curing resin and pre leaching material, which is the main technology of rapid molding and vacuum assisted molding (VARI). The cost of high performance carbon fiber composites is greatly improved by using the full composite materials. The manufacturing efficiency of composite materials is greatly improved. Although in recent years the domestic carbon fiber composite material technology has made considerable progress, but with foreign automotive composite material technology development and large-scale application of the gap, the specific analysis is as follows:

(1) demand traction. Due to the lack of market consumption power, policy support is not yet sound, the car manufacturers are not from the new energy vehicles to get high yields, seriously restricting the production of enthusiasm, investment funds to carry out new energy vehicles, it is difficult to achieve large-scale industrialization. By the entire new energy automobile industry development present situation, the carbon fiber composite material in the new energy automobile application also is in the exploration stage.

(2) gap in carbon fiber. Although in recent years, China's carbon fiber production capacity rapid amplification, but the gap is still there. Compared with foreign countries, the domestic raw silk is mostly high impurity content, the quality is not stable, the discrete coefficient is big, the cost also need to further reduce.

(3) gap in manufacturing technology of composite materials. To meet the fast paced low cost manufacturing related materials and automation equipment lag. The characteristics of the automotive industry requires that the composite materials should meet the requirements of the performance, but also meet the requirements of fast speed and low cost. At present, there are already some carbon fiber materials, which meet the requirements of low cost, and rapid manufacturing of resin materials and supporting technology. And, for the development of a rapid manufacturing set of digital, intelligent technology and equipment, to ensure that the automotive composite parts and components of the fast and accurate manufacturing. Although domestic related materials are also in the research and development, but has not yet formed the standard and realizes the industrial application.

(4) the design development and testing technology is backward, the capacity is insufficient. At present, the design software of composite material is from abroad, which is covered by the design of composite material, process simulation and mechanical performance analysis. Because of the research on the automotive composite materials, the design, analysis and Simulation of the material and technical data are not needed. The structural damage mode and failure criterion are difficult to be determined. The structure test method, criterion and test equipment are lack.

(5) the technology of composite material repair has not been fully studied. The repair materials and repair technology based on VAT technology need to be further promoted.

(6) the recycling technology is not yet mature, and a complete composite material recycling industry chain is not formed. It is necessary to carry out the research and development of the recycling technology of carbon fiber composite materials as soon as possible. The key technology of the application of the domestic automobile composite material industrialization

High performance composite materials to achieve large-scale applications in the car, the first need to design and build a mass production based composite material auto parts manufacturing system solutions. At present, whether it is the automotive OEM, auto parts enterprises, or composite parts manufacturing enterprises are not readily available based on mass production and low cost manufacturing system solutions. Building the solution requires the following key technologies: materials, design, manufacturing integrated product design technology, low cost, fast curing material (or low cost material) technology; low cost, automatic continuous integration manufacturing process technology; product (or component level) key performance testing technology; supporting repair materials and repair technology; composite materials recycling and recycling technology.

Domestic carbon fiber composite material in the light of the car manufacturing industry has just started, but also in the early stages of technology exploration and accumulation. Therefore, the application of carbon fiber composites in the automotive industry is not only necessary, but also more and more urgent. From the promotion of new materials and other strategic emerging industrial development, the national guide for the automotive industry and carbon fiber material industry is also more far-reaching significance. Carbon fiber composite material - Application of this industry chain involves many disciplines, many areas of basic science and technology issues, with the characteristics of cross strong, to the country to carry out a comprehensive top-level design, classification management, organization combination, set intelligence research, Co Construction Vehicle Enterprise - carbon fiber raw material - composite materials manufacturing enterprises of a series of key technologies, to build a mass production of composite material auto parts manufacturing system solutions. Gradually realize the automotive industry for composite material will not be used from the meeting, from simple to use a good change.