Southwest Aluminium breaks through many key technologies of Al-Li alloy

According to the bulk non-ferrous net reprint: Recently, the two-and-a-half years of Southwest Aluminum's key research project of "Industrial Preparation of New Lightweight High-performance Aluminum-Lithium Alloy" broke through a number of key technologies, achieving synergistic improvement in a number of properties and achieving industrialized production. The goal is to provide a strong guarantee for meeting the urgent needs of major aerospace projects such as China's key products, large aircrafts, and space stations.

Aluminum-lithium alloy materials are the most rapidly developing lightweight structural materials in aerospace materials in recent years. They have low density, high elastic modulus, high specific strength and specific rigidity, good fatigue performance, corrosion resistance, and good welding performance. Excellent overall performance. Using it instead of the conventional high-strength aluminum alloy can reduce the weight of the structural parts by 10% to 20% and the stiffness by 15% to 20%. Therefore, it shows a broad application prospect in the aerospace field and is considered to be the 21st century aerospace industry. Ideal for lightweight high-performance structural materials. In the aerospace giants such as the United States and Russia, due to the maturation of aluminum-lithium alloy development and forming technology, not only has a large number of applications on spacecrafts, but also the use of aluminum-lithium alloys for civilian aircraft has increased, such as the outer tank of the “Endeavour” space shuttle. Airbus A330/340/380 series aircraft.

According to relevant statistics, for every 1 kilogram of structural weight of aerospace structural parts, more than 10 times of economic benefits can be obtained, so the lower density aluminum-lithium alloys have received extensive attention from the aerospace industry, and aluminum-lithium alloys have been replaced on many aerospace components. Conventional high-strength aluminum alloys. After nearly 30 years of research and development, domestic aluminum-lithium alloys now have a large-scale research and development capability, which is of great significance to meet the needs of China's aerospace industry's advanced structural materials. At present, China’s key products and various space vehicles for space stations have imposed more stringent requirements on the overall performance of structural materials. The preparation of high-performance lightweight aluminum-lithium alloys has become a technical bottleneck that seriously restricts the development of key products in China, and the United States, Russia, and other countries are High-performance Al-Li alloy preparation technology and raw materials are strictly blocked. Therefore, independently developing a lightweight, high-performance aluminum-lithium alloy with excellent overall performance and achieving industrial mass production to meet the major needs of China's major aerospace projects such as key products, large aircrafts, and space stations is a major task facing our country’s relevant units.

For many years, Southwest China has always been committed to meeting the needs of the country. During the “Seventh Five-Year Plan” period, research and development of aluminum-lithium alloys began. It has been trial-produced and produced a variety of alloys.

In September of 2012, Southwest China began to undertake the “Industrial Preparation of New Lightweight High-performance Aluminum-Lithium Alloys” project. The majority of technical personnel actively thought of ways, added measures, and made innovations to give full play to their technological advantages and overcome difficulties. The lightweight high-performance aluminum-lithium alloy for aerospace research has been carried out to optimize composition, large-size ingot casting process, deformation and heat treatment process, and microstructure and material properties. After more than two years of continuous hard work, it has broken through the accurate control of alloy components. Large-scale ingot defect control, full fine microstructure control, large-scale plate deformation heat treatment and other key technologies have achieved synergy in the homogenization, strength, toughness, low temperature performance, and welding performance of large-size aluminum-lithium alloys, achieving industrialization. Preparation goal.