Development of high-speed railway carbon fiber

Development of high-speed railway carbon fiber

In recent years, China’s high-speed railways, which are designed and developed by China and have independent intellectual property rights, have frequently appeared, constantly refreshing the international community’s awareness of China’s high-speed rail. At present, there are more than 2,395 EMUs in China’s railways, ranking first in the world, with a safe running mileage of more than 3.74 billion kilometers. Through the digestion and absorption of imported technologies and bold innovation based on actual conditions, China’s high-speed rail has demonstrated the advantages of comprehensive system technology, low cost and fast construction speed in just ten years. It uses “China Speed” to display “Made in China”. Charm and strength.

Most people in the industry know that carbon fiber, a high-tech material with superior performance, can not be ignored in the “China Speed” of high-speed rail. Its significance to high-speed rail is mainly reflected in the following two aspects: First, the realization of high-speed rail body lightweight. Carbon fiber is light in weight and has a density of only 1.78 g/cm3, which is similar to plastic, but its strength is more than 7 times higher than that of steel. The use of carbon fiber parts can reduce the proportion of traditional steel structures in high-speed rail bodies. The ultra-lightweight of the high-speed rail is beneficial to reduce the resistance to driving, directly reduce energy consumption, reduce carbon dioxide emissions, and achieve speed.

The second is to increase the safety of high-speed rail operation. The faster the high-speed rail runs, the higher the durability requirements for the various parts of the car body. For example, at the end of 2010, the “Harmony” CRH380A was jointly tested and integrated on the Zaozhuang-Dongyu route of the pilot section of the Beijing-Shanghai high-speed railway. During the test, the speed of 486.1 kilometers was oscillated, but the impact of this high speed on the bearing of the train was very large. After the impact high speed, almost all the bearings on the train were replaced. Although the speed reduction of the high-speed rail is now carried out, the average speed of the high-speed rail is also more than 200 kilometers per hour. This requires materials with strong tolerance to ensure the safe operation of the high-speed rail. The strength of carbon fiber material is up to 3600 MPa, especially the steering wheel made of carbon fiber. The mechanical strength and impact resistance are increased by 35% and 20% respectively compared with ordinary materials. The overall vehicle strength is theoretically at least 20%-30% stronger than that of ordinary materials, and it is not afraid of corrosion of chemical substances such as acid and alkali salts, and has a long service life.

In addition, high-speed rail needs to cross a region with a large temperature difference in a short period of time. From Harbin in the snow and ice to Guangzhou in the spring, the temperature difference in a short period of time needs to maintain zero deformation of parts, which is a huge for ordinary materials. The challenge, but for carbon fiber, it is its strength. At present, carbon fiber composite materials can be applied to non-load bearing and secondary bearing components such as train interiors, pantographs and equipment compartments, as well as main bearing components such as car bodies and bogies.

When high-speed rail manufacturing showed a clear demand for carbon fiber, many carbon fiber processing and manufacturing companies also targeted the high-speed rail market in a timely manner and actively docked the industry. The carbon fiber precursor is pre-oxidized and carbonized at a high temperature of 2000-3000 degrees Celsius, and can withstand high temperatures up to thousands degrees Celsius. However, in specific applications, the carbon fiber precursor is mainly in the form of a carbon fiber composite material. Therefore, the composite material must have the excellent properties of the original yarn while also having other characteristics to achieve high-iron environmental protection. High standards in safety and so on.

To this end, a large number of R & D teams have been working hard to develop carbon fiber composite materials with various properties such as flame retardant, high temperature resistance, toughening, shock resistance and waterproofing through a large number of modification experiments on matrix resin to meet the development of high iron. New demand.

At present, China’s high-speed rail construction is in a period of prosperity. Through years of hard work and accumulation, China has fully mastered the core technology of high-speed railways, and the overall level of the industry has ranked among the world’s first. On the intertwined track, the “China Speed” of high-speed rail and electric power represents that “Made in China” has been on the road of independent intellectual property development. In this process, the use of new carbon fiber materials not only promotes the light weight of high-speed trains, but also drives the high-speed rail manufacturing industry to achieve new changes and further enhance the “China speed.”