Domestic aluminum production development and application status

Recently, the Ministry of Industry and Information Technology held the first working meeting of the upstream and downstream cooperative mechanism of civil aircraft aluminum materials, and emphasized the vigorous promotion of the complete supply of aviation aluminum materials. With the completion of the domestic assembly of large planes in the C919 assembly line and the acceleration of the promotion of the regional aircraft ARJ21, China’s demand for aviation aluminum will enter a period of rapid growth. This is both a new opportunity for development in the aviation industry and the aluminum industry. new challenge.

Aluminum alloy is a kind of high-performance non-ferrous metal material which is synthesized from pure aluminum and copper, silicon, magnesium, zinc, manganese and other alloying elements. It is widely used in aviation, aerospace, weapons, nuclear industry, high-speed trains and other fields, in which aluminum alloy The application in the aviation field is particularly extensive, and is known as "a hundred years of aviation, a hundred years of aluminum alloy." As one of the main body materials that make up an aircraft, aluminum alloy has a very important position in aviation manufacturing.

Rapid development of aviation aluminum

In 2011, China's first aluminum alloy thick plate production line supporting the national large aircraft project was completed and put into operation in the southwestern aluminum, making China another major producer of aluminum alloy plates following the United States, Japan, Germany and Russia. s country. The completion and production of this production line has realized the long-cherished wish of several generations of aluminum processors to further improve the overall level of development of China's aluminum processing industry, enhance the national defense construction and aviation industry's urgent need of aluminum alloy materials, and boost China’s large aircraft construction. Is extremely important.

The completion of the production of heavy plate production line is only the first step in the development of aviation aluminum. Aluminum production continuously enhances the capacity for 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 by the market, represent international and domestic advanced levels, and fill domestic gaps. A series of scientific and technological achievements with independent intellectual property rights have provided high-quality aluminum materials for China's aviation, aerospace, defense, and national key construction projects.

In recent years, China's aviation aluminum processing companies have continued to strengthen their exploration of foreign exchanges and cooperated with such leading aviation manufacturing companies as Boeing, Airbus, Safran, and Bombardier to further improve aviation aluminum processing. “The development and processing technology of aluminum materials 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 processes, and the existing technology management model has been difficult to adapt to the aviation users. The refined requirements for the quality control of the product process, and because the advanced aerospace material 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 companies.” Southwest Aluminium Chief Engineer Li Yong analyzed.

Aviation products often have problems with many orders, small quantities, difficulties in production group approval, low product yields, and poor stability, which seriously affect the enthusiasm of customers for using domestic aviation materials. In order to improve aviation aviation's urgent need of aluminum alloy materials, and to seize opportunities in the aviation field, it is necessary to build an independent innovation material system and equipment technology system, to solve the difficulties in material research and development, and to further improve the level of research and development of new materials.

The successful development of super-large arc die forgings is a successful example of China's implementation of independent innovation. This die forging is a key die forging part of an aircraft. It has a thin thickness, a large curvature, and is easy to be deformed. It has a high requirement for the die forging process and is a high-tech product with high added value. Until now, our country has been unable to produce. In order to break through this technical difficulty, SWA has set up a dedicated research team, boldly implemented technological innovations, and successfully solved the forging forming technology and oversized arc mode of super-equipment capabilities by adopting special tools for manufacturing, updating and optimizing production processes and other measures. Forging size control technology, large-scale die forging stress removal technology and a series of problems, refreshing China's history of die forging production, the heaviest, the largest projection area of ​​the historical record, to fill the gaps in the country.

Civil aircraft aluminum alloy application status

From the statistical analysis of related data, the current major civil aircraft in the world, the amount of aluminum materials are more than 70%, of which the most widely used is Al-Cu alloy (2xxx) and Al-Zn-Mg alloy (7xxx) series aluminum Alloys, mainly used in aircraft skin, frame beams, wall panels, fuel tanks and so on. Although composite materials can significantly reduce the weight of aircrafts, they are expensive to manufacture, difficult to maintain in the later period, and poor in heat and moisture. Aluminum has accumulated sufficient practical experience in many years of application, and its performance characteristics have been fully verified. From the point of view of the entire industry life cycle, composite materials may not maintain their advantages in terms of quality, cost, and environmental protection. Europe and the United States have reservations about whether to further expand the scope of application of composite materials, which provides a good opportunity for the development of aluminum materials. The timely introduction of new aluminum materials that meet new requirements is particularly important.

With the decreasing trend of the proportion of traditional aluminum alloy applications, the application of new aluminum-lithium alloys has gradually increased. For aluminum alloys, lithium is the best element to reduce density and increase specific stiffness. Airbus A350 innovative use of aluminum-lithium alloy fuselage skin and floor structure, the amount of body weight to achieve 22%; A380 fuselage skin, floor beams, front and rear edges of the aircraft are using aluminum lithium alloy; Bombardier In the C-Series aircraft, advanced aluminum-lithium alloy parts have accounted for 20% of the total aircraft materials; the EH101 multi-purpose helicopter has adopted a large number of aluminum-lithium alloys. In China, the straight sections such as the fuselage of the large passenger aircraft C919 are the first aluminum-lithium alloys used in civilian aircraft production.

With the continuous improvement of aircraft speed, life, and environmental protection 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. The new alloy material. The future development of aluminum materials must be continuously improved on the basis of the original, reduce production costs, improve formability and serviceability, and accelerate the development of high purity, high uniformity, ultra-fine aluminum alloy, low internal stress aluminum plate, and Improves the overall manufacturing capacity of thick plates, improves the machinability and grinding of aluminum materials, adapts the process of aging forming and superplastic forming, and improves weldability, and develops aluminum alloy powders that can be rapidly used in laser rapid near/net forming. The new aluminum heat treatment technology is a difficult and important point in the research and development of aluminum alloy materials and manufacturing technologies.

Collaborate to win the future

“Production of large-scale commercial aircrafts and the realization of autonomous supply of aviation aluminum materials are strategic choices to implement the “Made in China 2025” strategy and create new advantages in China's high-end manufacturing.” In September 2015, the Ministry of Industry and Information Technology organized a cooperation mechanism for upstream and downstream aluminum equipment for civil aircraft in Shanghai in September 2015. The first working meeting will encourage the development and production of aluminum materials for civil aircraft, and will actively coordinate resolution and reflection on difficult issues. For the aviation industry and the aluminum industry, it is undoubtedly a good news and an important guide for future industry development.

In the future, with the development of aerospace aluminum materials toward high strength, high toughness, damage resistance, fatigue resistance, low density, weldability, low anisotropy, and strong thermal stability, domestic aluminum will surely follow the new aluminum alloy. The pace of material needs has progressed in tandem with the advancement of our country from a "manufacturing power" to a "manufacturing power."