High-speed development of aviation aluminum
In 2011, China's first aluminum alloy thick plate production line supporting the national large aircraft and other projects was completed and put into production, making China a country that can realize large-scale production of aluminum alloy thick plates after the United States, Japan, Germany and Russia. The completion and commissioning of this production line has fulfilled the wish of several generations of aluminum processing industry workers, and further improved the overall development level of China's aluminum processing industry, improved the support capacity of China's national defense construction and aviation industry, and urgently needed aluminum alloy materials, and boosted China's large aircraft. Construction is of paramount importance.
The completion and production of the thick plate production line is only the first step in the development of aviation aluminum. Aluminum production continuously enhances the ability of independent innovation and construction, breaks through a number of key technologies, solves a series of major key technical problems, and develops a large number of new products and technologies that are urgently needed in the market, represent the international and domestic advanced level, and fill the domestic gap. A series of scientific and technological achievements with independent intellectual property rights have provided high-quality aluminum materials for China's aerospace, national defense military and national key construction projects.
In recent years, China's aviation aluminum processing enterprises have continuously strengthened their foreign exchange and exploration, and cooperated with well-known aviation manufacturing companies such as Boeing, Airbus, Safran and Bombardier to further improve the level of aviation aluminum processing.
"Aluminium material development and processing technology determines the development level of a country's aerospace industry to a certain extent. Aviation aluminum materials usually have high comprehensive performance requirements and long production process, and the existing technology management model has been difficult to adapt to aviation user units. The finer requirements for quality control of product process. Moreover, as advanced aerospace materials products are in the initial stage of localization, it is an indisputable fact that our competitiveness is not strong compared with foreign advanced aluminum processing enterprises. The staff analyzed it. Aviation products usually have problems such as large order quantity, small quantity, difficulty in production group approval, low product yield and poor stability, which seriously affect the enthusiasm of customers to use domestic aviation materials. In order to improve the aviation industry's urgent need for aluminum alloy materials, and to seize the opportunities in the aviation field, it is necessary to build an independent and innovative material system and equipment technology system, to solve the problems in material research and development in a targeted manner, and further improve the research and development level of new materials.
Application status of civil aircraft aluminum alloy
From the statistical analysis of relevant data, the main domestic civil aircraft, the amount of aluminum is more than 70%, of which the most used are Al-Cu alloy (2xxx) and Al-Zn-Mg alloy (7xxx) series aluminum Alloy, mainly used for aircraft skins, frame beams, siding, fuel tanks, etc.
Although the composite material can significantly reduce the weight of the aircraft, it is expensive to manufacture, difficult to maintain in the later stage, and has poor moist heat. The aluminum material has accumulated enough practical experience in many years of application, and its performance characteristics have been fully verified. From the perspective of the entire industry life cycle, composite materials may not be able to maintain their advantages in terms of quality, cost and environmental protection. Europe and the United States also have reservations on whether to further expand the application of composite materials, which provides a good opportunity for the development of aluminum materials. It is particularly important to introduce new aluminum materials that meet the new requirements in a timely manner.
With the decreasing proportion of traditional aluminum alloy applications, the application of new aluminum-lithium alloys has gradually increased. For aluminum alloys, lithium is the best element for reducing density and increasing specific stiffness. The Airbus A350 innovatively uses aluminum-lithium alloy to make fuselage skin and floor structure, which is 22% of the weight of the fuselage; A380 fuselage skin, floor beam, and front and rear edges of the wing are all made of aluminum-lithium alloy; Bombardier Among the C-series aircraft, advanced aluminum-lithium alloy material components have accounted for 20% of the total aircraft materials; EH101 multi-purpose helicopters use a large number of aluminum-lithium alloys. In China, the straight section of the fuselage of the large passenger aircraft C919 is the first use of aluminum-lithium alloy in the production of civil aircraft.
With the continuous improvement of aircraft speed, life, environmental protection and other requirements, the aviation industry needs higher specific strength, high specific stiffness, high toughness, high heat resistance, high fatigue life, high corrosion resistance, high damage tolerance, and easy processing. New alloy material.
In the future, the development of aluminum materials must be continuously improved on the basis of the original, reduce production costs, improve formability and performance, and accelerate the development of high-purity, high-uniformity, ultra-fine aluminum alloy, low internal stress aluminum slabs, and Improve the overall manufacturing capacity of thick plates, improve the machinability and grinding of aluminum, process adaptability of ageing and superplastic forming, weldability, and research and development of aluminum alloy powders that can be quickly used for laser rapid near/net forming. The new aluminum heat treatment technology is the difficulty and focus of research and development of aluminum alloy materials and manufacturing technology.