[Expanding aluminum application]China’s self-developed aluminum-based composite double-deck EMU is exported to Europe

Recently, China’s first aluminum-based composite double-deck EMUs exported to Europe rolled off the production line of CRRC Zhuzhou Machinery Co., Ltd. This train set is independently developed by China and is a double-deck EMU that can fully meet the technical specifications for interconnection and interoperability of EU railway systems. The maximum operating speed is 200km/h, featuring large passenger capacity, flexible marshalling, safety and reliability, intelligent control, riding comfort, and low noise. It will run on railways in Austria, Germany, Hungary, Switzerland, and the Czech Republic.

It is understood that in December 2019, CRRC Zhuji signed a contract with an Austrian company to supply railway double-decker passenger sports cars. After that, CRRC Zhuji immediately organized personnel to carry out design, R&D, manufacturing, and commissioning work, which only took 18 In May, the first aluminum-based composite double-deck EMU was successfully rolled off the assembly line. The project cycle was shortened by more than half compared with the international products of the same type, demonstrating the creativity of the Chinese.
The basic form of the off-line train is 2 moving, 4 towing and 6 sections, with 571 passengers and a maximum of 1280 passengers, which is 30% to 35% higher than the capacity of single-deck trains, which will relieve the tension on European lines. The situation has a greater effect. At the same time, the car group uses a large number of aluminum-based composite materials, so that the quality of the double-layer vehicle is only about 10% higher than the quality of the single-layer vehicle, the power consumption is only increased by about 12%, and the greenhouse gas emissions only increase by about 10%. 12%.
The aluminum-based composite materials used to manufacture the body of the double-deck EMU are composed of 75% of the 6XXX series aluminum Alloy as the matrix, and carbon fiber and glass carbon fiber as the reinforcement. Due to the addition of carbon fiber, the material has many excellent properties. For example, the density of carbon fiber is only 1.85g/cm3, which can greatly reduce the density of aluminum-based composites. At the same time, carbon fiber has a tensile strength of up to 7000MPa, which makes aluminum-based composites. The tensile strength of the material is greatly improved. Therefore, aluminum-based composite materials with light weight, good rigidity and high strength are currently one of the most ideal materials for manufacturing high-speed rail car bodies and double-deck motor car bodies.
In addition, carbon fiber and glassy carbon fiber reinforced aluminum alloy matrix composites have the following advantages: small thermal expansion coefficient and good dimensional stability. The addition of a considerable amount of reinforcing fibers not only greatly improves the strength and modulus of the material, but also significantly reduces the thermal expansion coefficient of the composite material. Good high temperature performance. The composite material still has a high temperature strength of 600MPa at 500°C, while the strength of 6063 alloy has dropped below 100MPa at 300°C. Good fatigue performance and fracture toughness. The fiber and the aluminum alloy matrix have a good interface bonding state, which can not only effectively transfer the load, but also prevent crack propagation, improve the fracture toughness of the material, and the fatigue strength to tensile strength ratio of the carbon fiber/aluminum alloy composite material can reach about 0.7 . (Wang Zhutang)